坂入 正敏 (サカイリ マサトシ)

工学研究院 材料科学部門 マテリアル設計分野准教授
Last Updated :2025/02/13

■研究者基本情報

学位

  • 工学博士, 東京工業大学

Researchmap個人ページ

研究キーワード

  • 腐食・防食
  • 鉄鋼材料
  • アルミニウム
  • アノード酸化
  • 微細加工
  • めっき
  • 液相析出
  • 表面・界面制御
  • 局部溶解
  • フォトンラプチャー法
  • 皮膜再生機構
  • レーザー照射
  • 電解コンデンサー
  • 複合酸化物皮膜
  • パルスYAGレーザー
  • 局部めっき
  • Electrochemistry
  • Surface Finishing
  • Corrosion Science

研究分野

  • ナノテク・材料, 材料加工、組織制御

担当教育組織

■経歴

委員歴

  • 2022年05月 - 現在
    日本鉄鋼協会, サステナシステム部会 部会長, 学協会
  • 2021年06月 - 現在
    軽金属学会, 北海道支部長, 学協会
  • 2010年03月 - 現在
    (公社)日本化学会, 化学グランプリ・オリンピック委員会委員, 学協会
  • 2021年01月 - 2022年12月
    腐食防食学会, 北海道支部長, 学協会
  • 2017年01月 - 2018年12月
    表面技術協会, 北海道支部長, 学協会

■研究活動情報

受賞

  • 2017年03月, 日本鉄鋼協会, 学術記念賞(西山記念賞)               
    微小電気学的手法による鉄鋼材料の腐食の研究
    坂入 正敏
  • 2017年01月, 北海道大学, 教育総長賞(奨励賞)               
    坂入 正敏
  • 1991年05月, 腐食防食協会進歩賞               
    日本国

論文

  • Ion-selectivity of galvanic corrosion products formed in multi-material gaps under atmospheric corrosion conditions with anti-freezing salts
    Kosaku Nomura, Masatoshi Sakairi, Koji Fushimi
    Corrosion Science, 2024年08月
    研究論文(学術雑誌)
  • Year-round Monitoring of Temperature and Humidity using a Sensor Network installed in the Hokkaido Centennial Memorial Tower
    Kazuhisa Azumi, Masatoshi Sakairi, Koji Fushimi, Takashi Sato, Ken Mikami, Masazumi Miura
    Tetsu-to-Hagane, 2024年
    研究論文(学術雑誌)
  • Miniature pH detection probe for in-situ monitoring of cement paste inside
    Koji Fushimi, Tomoya Takano, Yoganandan Govindaraj, Ryosuke Saito, Masatoshi Sakairi
    Electrochimica Acta, 441, 141776, 141776, Elsevier BV, 2023年02月
    研究論文(学術雑誌)
  • 油性環境の凝縮水中でMo含有ステンレス鋼に形成される皮膜の解析               
    加藤雅貴, 坂入正敏
    材料と環境, 2023年, [査読有り], [最終著者]
    研究論文(学術雑誌)
  • Passivity of iron surface in curing cement paste environment investigated by electrochemical impedance spectroscopy and surface characterization techniques
    Sourav Kr. Saha, Tomoya Takano, Koji Fushimi, Masatoshi Sakairi, Ryosuke Saito
    Surface and Interface, 36, 102549, ELSEVIER, 2023年, [査読有り]
    英語, 研究論文(学術雑誌), The curing behaviour of cement paste and formation of passive film on iron were investigated by electrochemical techniques and X-ray photoelectron spectroscopy (XPS). Open circuit potential of iron was monitored with the newly developed solid-contact-chloride reference electrode in cement paste with pH -13 laid at -0 VSHE for 56 d, indicating iron was kept in passive state. Electrochemical impedance spectroscopy results showed significant increasing trend of film and cement paste resistance with curing time. XPS elucidated formation of ferric hydroxide and ferric oxide was efficient to passivate the iron rather than ferrous products. Iron surface receded from corrosion due to high-alkaline environment of cement paste and formation of passive film.
  • 積雪環境下における鋼材の埋雪深さが腐食挙動に与える影響の評価               
    衣笠潤一郞, 坂入正敏
    材料と環境, 72, 1, 9, 2023年01月, [査読有り], [最終著者]
    日本語, 研究論文(学術雑誌)
  • Influence of Metal Cations on Corrosion Behavior of Aluminum Alloy 2024-T3 in Model Freshwater               
    Li Li, Masatoshi Sakairi, Md. Saiful Islam, Akira Kaneko
    Materials Trans action, 64, 540, 548, 2023年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Influence of Fe3+ on titanium corrosion in H2SO4 solutions without and with F
    Xin Xin Liu, Masatoshi Sakairi, Qiang Qiang Liao
    Corrosion Reviews, 41, 1, 73, 83, Walter de Gruyter GmbH, 2022年12月09日
    研究論文(学術雑誌), Abstract

    Influence of Fe3+ on the corrosion of titanium in H2SO4 solution without F and with F was investigated by electrochemical tests. The electrochemical test results showed that Fe3+ could significantly inhibit titanium corrosion in H2SO4 solution without F and with F by promoting the protective film formation on titanium. Titanium corrosion resistance (Rc) was positively related to the concentration of Fe3+ in H2SO4 without and with F. A mechanism was proposed for Fe3+ inhibiting the corrosion of titanium in H2SO4 solution without and with F.
  • Gravimetric corrosion tests and surface analysis of SUS 310S in model seawater               
    Md. Saiful Islama, Most. Sabina Yasminc, Masatoshi Sakairi
    Journal of Materials Science Research and Reviews, 9, 1, 22, 30, 2022年09月, [査読有り], [国際共著], [国際誌]
    英語, 研究論文(学術雑誌)
  • 薄い液膜下における鋼の腐食に及ぼす腐食抑制剤の影響               
    門馬悠一郎, 坂入正敏, 大谷恭平, 上野義文
    材料と環境, 71, 133, 137, 2022年05月
    日本語, 研究論文(学術雑誌)
  • 膜厚制御された液膜下における炭素鋼の電気化学挙動               
    門馬悠一郎, 坂入正敏, 大谷恭平, 上野義文
    材料と環境, 71, 4, 121, 125, 2022年04月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Effects of metal cations on corrosion morphology of carbon steel in model fresh water               
    Li Li, M. Sakairi
    Zairyo-to-Kankyo, 71, 208, 212, 2022年, [査読有り], [最終著者]
    英語, 研究論文(学術雑誌)
  • 炭素鋼の腐食におよぼすイミダゾリン系腐食インヒビターの影響               
    野口息吹, 坂入正敏, 水上裕貴, 砂場敏行
    材料と環境, 71, 176, 179, 2022年, [査読有り]
    日本語, 研究論文(学術雑誌)
  • 炭素鋼およびアルミニウム合金の電気化学挙動に及ぼす溶液温度の影響               
    沈 童, 坂入正敏
    材料と環境, 71, 133, 137, 2022年, [査読有り], [最終著者]
    日本語, 研究論文(学術雑誌)
  • Corrosion behavior of A6061 aluminum alloy in cation containing aqueous medium               
    Md.Sairufl Islam, M. Sakairi
    Corrosion Communications, 5, 39, 48, 2022年, [査読有り], [最終著者], [国際共著], [国際誌]
    英語, 研究論文(学術雑誌)
  • 金属上に形成した水膜中の酸素拡散挙動に及ぼす水膜厚さと温度差の影響               
    坂入正敏, 谷口雅也
    鉄と鋼, 107, 12, 1029, 1035, 2021年12月, [査読有り], [筆頭著者]
    日本語, 研究論文(学術雑誌)
  • 環境因子を考慮した炭素鋼の大気腐食モデリングとシミュレーション               
    五十嵐誉廣, 小松篤史, 加藤千明, 坂入正敏
    鉄と鋼, 107, 12, 2021年12月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • 模擬淡水における炭素鋼の腐食挙動に及ぼす金属カチオンの影響               
    李礼, 坂入正敏
    鉄と鋼, 107, 12, 2021年12月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Synergistic Effects of Metal Cations and Sodium Gluconate on the Inhibition of Freshwater Corrosion of Mild Stee
    K. Otani, M. Sakairi
    Materials Transactions, 62, 6, 815, 820, Japan Institute of Metals, 2021年06月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Hydrogen permeation behavior of steel under wet/dry corrosion with changes in relative humidity at the dry               
    X. Han, M. Sakairi
    ISIJ International, 61, 4, 1192, 1198, 2021年04月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Hydrogen permeation behavior of scratch formed on Zn coated steels in simulated atmospheric corrosion environment               
    K. Sakata, M. Sakairi, J. Kinugasa
    ISIJ International, 61, 4, 1118, 1124, 2021年04月, [査読有り]
    英語
  • Hydrogen permeation behavior of scratch on Zn coated steel during 1000 hours wet and dry corrosion test               
    K. Sakata, M. Sakairi, J. Kinugasa
    ISIJ International, 61, 4, 1125, 1132, 2021年04月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Effect of scratch size on hydrogen permeation behavior of zinc coated steel during wet and dry corrosion tests               
    M. Sakairi, T. Hashimoto
    ISIJ International, 61, 4, 1097, 1101, 2021年04月, [査読有り], [筆頭著者]
    英語, 研究論文(学術雑誌)
  • Hydrogen Absorption Mechanism into Iron in Aqueous Solution including Metal Cations by Laser Ablation Tests and First-principles Calculations
    T. Igarashi, K. Otani, C. Kato, Y. Togashi, M. Sakairi, K. Baba, S. Takagi
    ISIJ International, 61, 4, 1085, 1090, Iron and Steel Institute of Japan, 2021年04月, [査読有り]
    研究論文(学術雑誌)
  • Electrochemical Studies on the Corrosion Behavior of Mild Steel in NaCl Aqueous Solutions with Zinc Ions               
    Md. Islam Saiful, Masatoshi Sakairi
    Journal of Materials Science Research and Reviews, 7, 2, 152120, 13, 2021年02月, [査読有り], [国際共著], [国際誌]
    研究論文(学術雑誌)
  • Local Electrochemical Measurements by 3D Printed Sf-MDC Equipped with Optical Microscope               
    K. Sakata, M. Bilal, M. Sakairi, T. Murata
    Journal of the electrochemical society, 168, 061505, 2021年, [査読有り]
    英語, 研究論文(学術雑誌)
  • High throughput electrochemically driven metal microprinting with multicapillary droplet cell               
    M. Bilal, M. Sakairi
    Materials Today Communications, 26, 102053, 2021年, [査読有り], [国際誌]
    英語, 研究論文(学術雑誌)
  • Carbon nanohorn coating by electrodeposition accelerate bone formation on titanium implant
    Sari Takada, Eri Hirata, Masatoshi Sakairi, Eijiro Miyako, Yuta Takano, Natsumi Ushijima, Masako Yudasaka, Sumio Iijima, Atsuro Yokoyama
    Artificial Cells, Nanomedicine, and Biotechnology, 49, 1, 20, 29, Informa UK Limited, 2021年01月01日, [査読有り], [国際誌]
    英語, 研究論文(学術雑誌), Direct contact between bone and implant materials is required for dental implants. Titanium is used for the implant material owing to its mechanical and biological properties. The anodisation as the surface treatment was employed to enhance osteogenesis around titanium. Moreover, carbon nanohorn (CNH), a type of nanometer-sized carbon material, was reported to promote the bone formation. Thus, it is expected that if the surface of anodised Ti (AnTi) is modified with CNHs, Ti-bone contact would be enhanced. In this study, the Ti surface was modified with CNHs by electrophoresis and obtained anodised titanium coated with CNHs (CNH/AnTi). In vitro, CNH/AnTi attracted osteoblastic cells more than AnTi, thereby the proliferation of osteoblastic cell was enhanced by CNH/AnTi more than by AnTi. In vivo, at 7 and 28 days after implantation of CNH/AnTi or AnTi into the rat femur, more aggressive bone formation was observed on the surface of CNH/AnTi than on AnTi. More importantly, the area where newly formed bone tissue directly attached to CNH/AnTi was significantly larger than that for AnTi, suggesting that "contact osteogenesis" was accelerated on CNH/AnTi during the early post-implantation period. CNH/AnTi would be advantageous especially for the early stages of bone regeneration after surgery.
  • Corrosion behaviour of Al-containing high Cr ferritic oxide dispersion strengthened steel in nitric acid environment
    R. Priya, S. Ningshen, M. Sakairi, S. Ukai
    Journal of Nuclear Materials, 534, 152120, 152120, Elsevier BV, 2020年06月, [査読有り], [国際共著], [国際誌]
    研究論文(学術雑誌)
  • 3D printed solution flow type microdroplet cell for simultaneous area selective anodizing               
    Bilal Muhanmad, Masatoshi Sakairi
    Journal of Advanced Research, 26, 11, 43, 61, 2020年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Fast fabrication of localized porous alumina patterns with 3D printed microdroplet cell               
    Bilal Muhanmad, M. Sakairi
    Fast fabrication of localized porous alumina patterns with 3D printed microdroplet cell, 167, 081501, 2020年, [査読有り]
    研究論文(学術雑誌)
  • Auger electron spectroscopic analysis of corrosion products formed on A3003 aluminum alloy in model fresh water with different Zn2+ concentration
    Kyohei Otani, Md. Saiful Islam, Masatoshi Sakairi, Akira Kaneko
    Surface and Interface Analysis, 51, 12, 1207, 1213, John Wiley and Sons Ltd, 2019年12月01日
    英語, 研究論文(学術雑誌), The corrosion morphology and composition of corrosion products of A3003 formed in model fresh water with different Zn2+ concentrations were investigated by immersion tests combined with surface observations and analysis using an Auger electron spectroscope (AES). The cross-sectional AES observations showed that the thickness of the corrosion product layer formed on A3003 decreases with increases in the Zn2+ concentration of the model fresh water. A cross-sectional AES point analysis suggested that the corrosion products formed on the A3003 in the Zn2+ containing model fresh water (Zn2+ >
     0.1 mM) have a multilayered structure and that the inner of Zn-rich layer would have high corrosion protective properties.
  • Effects of solution compositions on corrosion behavior of 13 mass% Cr martensitic stainless steels in simulated oil and gas environments               
    M. Sakairi, H. Mizukami, S. Hashizume
    AIMS Materials Sciences, 6, 288, 300, 2019年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Corrosion inhibition of mild steel by metal cations in high pH simulated fresh water at different temperatures               
    Md. Saiful Islam, M. Sakairi
    Corrosion Science, 153, 100, 108, 2019年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Effect of Anodizing Time on Multiscale Porous Structure of Ti-Al Alloy Microchannel Wall               
    T. Ohmi, T. Yamamori, M. Sakairi
    Materials Transaction, 60, 519, 524, 2019年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Effects of Zn2+ concentration on the corrosion of mild steel in NaCl aqueous solutions               
    Md. Saiful Islam, M. Sakairi
    Journal of the electrochemical society, 166, 2, C83, C90, 2019年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Auger electron spectroscopic analysis for corrosion products formed on A3003 aluminum alloy in model fresh water with different Zn2+ concentration               
    K. Otani, Md. Saiful Islam, M. Sakairi, A. Kaneko
    Surface and Interface Analysis, 1, 7, 2019年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Studies on corrosion inhibition by metal cations for mild steel in simulated fresh water at high temperature               
    Md. Saiful Islam, Kyohei Otani, Masatoshi Sakairi
    材料と環境, 67, 11, 457, 461, 2018年11月, [査読有り]
    英語, 研究論文(学術雑誌)
  • 溶液フロー型微小液滴セルを用いるアルミニウムの局部アノード酸化と貫通型ポーラスアルミナの作製               
    松本敏幸, 坂入正敏
    軽金属, 68, 8, 401, 407, 2018年08月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Influence of metal cations on inhibitor performance of gluconates in the corrosion of mild steel in fresh water
    Kyohei Otani, Masatoshi Sakairi, Md. Saiful Islam
    Corrosion Reviews, 36, 1, 105, 113, Walter de Gruyter GmbH, 2018年02月23日, [査読有り]
    英語, 研究論文(学術雑誌), The influence of metal cations on the ability of gluconates to inhibit corrosion of mild steel in a model fresh water was investigated by electrochemical impedance spectroscopy (EIS) and immersion tests. The EIS and immersion test results showed that the corrosion inhibition of mild steel in model fresh water by gluconates was improved by metal cations that have a large value of corrosion inhibitory effect of cation, Y. The X-ray photoelectron spectroscopy (XPS) analysis showed that metal cations that have larger Y values are bonded on mild steel. It was thought that metal cations with large Y values and gluconates confer a synergistic inhibition effect on the corrosion of mild steel in model fresh water.
  • Corrosion-induced morphological changes and the mechanism of A3003 aluminum alloy in model sea water containing gluconates and zinc ions
    Kyohei Otani, Masatoshi Sakairi, Akira Kaneko, Daisuke Nagasawa
    Keikinzoku/Journal of Japan Institute of Light Metals, 68, 1, 16, 21, Japan Institute of Light Metals, 2018年, [査読有り]
    日本語, 研究論文(学術雑誌), Corrosion mechanism and morphology changes of aluminum alloy in model solution corresponding sea water containing gluconates and zinc ions were investigated by immersion corrosion tests with surface analysis. Surface and cross-sectional SEM results showed that zinc ions suppress the morphology changes of aluminum alloy in the solution containing gluconates. XPS analyses indicated that gluconates in the solutions adsorb on the oxide films of aluminum alloy and protective films of the adsorbed gluconates would prevent the penetration of chloride ions to the aluminum alloy. The XPS results also suggest that zinc ions in the solutions bond to the oxide film of aluminum alloy and zinc ions enhance the corrosion inhibition ability of the protective films of gluconates for aluminum alloy in model sea water.
  • Role of metal cations on corrosion of metallic materials in aqueous environments               
    M. Sakairi, K. Otani, Md. Saiful Islam
    Proc. of the 9th International Symposium on Marin Corrosion and Control, 31, 32, 2018年, [招待有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Corrosion performance of 13%Cr martensitic stainless steels in supercritical CO2 environments               
    S. Hashizume, M. Sakairi
    Proc. of Latincorr 2018, L2018-007, 2018年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • 金属カチオンによるボイラー給水環境における鋼の腐食抑制効果               
    坂入正敏, 安住和久, Md. Saiful Islam
    ボイラ研究, 411, 10, 10, 17, 2018年, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Corrosion inhibition effects of metal cations on SUS304 in 0.5 M Cl− aqueous solution
    Md. Saiful Islam, Kyohei Otani, Masatoshi Sakairi
    Corrosion Science, 140, 8, 17, Elsevier Ltd, 2018年, [査読有り]
    英語, 研究論文(学術雑誌), The corrosion characteristics of SUS304 exposed to 0.5 M Cl− aqueous solution containing different metal cations were studied with immersion tests, surface analysis and electrochemical tests. The mechanism of corrosion with metal cations was clarified by the XPS analysis results together with the hard and soft acid and base (HSAB) concept and the passive films structure. It is supposed that metal cations with large hardness make a layer by chemical bonding with the passive films. The passive films are protected by the metal cation layer from Cl− attack, and consequently corrosion reactions are inhibited.
  • Role of metal cations on corrosion of coated steel substrate in model aqueous layer               
    Md. Saiful Islam, Kyohei Otani, Masatoshi Sakairi
    ISIJ International, 58, 9, 1616, 1622, 2018年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Effect of metal cations on corrosion of mild steel in 10 mM Cl- aqueous solution               
    Md. S. Islam, K.i Otani, M. Sakairi
    Corrosion Science, 131, 17, 27, 2018年, [査読有り]
    英語, 研究論文(学術雑誌)
  • グルコン酸や亜鉛イオンを含む模擬海水におけるアルミニウム合金の腐食による形態変化とその機構               
    大谷恭平, 坂入正敏, 兼子 彬, 長澤大介
    軽金属, 68, 1, 1, 6, 2018年, [査読有り]
    日本語, 研究論文(学術雑誌)
  • 温度条件によるZn板上に形成したNaCl水膜中の酸素拡散挙動変化               
    坂入正敏, 坂木亮太
    材料と環境, 66, 12, 401, 404, 2017年12月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • 大気腐食によるめっき鋼板からの透過水素ときず面積との関係
    橋本拓海, 坂入正敏, 湯瀬文雄, 漆原 亘
    材料と環境, 66, 11, 357, 360, 腐食防食学会, 2017年11月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Ti-Al 系マイクロチャンネル内壁のマルチスケールポーラス構造に及ぼす陽極酸化時間の影響               
    大参達也, 山森 樹, 坂入正敏
    軽金属, 67, 11, 589, 594, 2017年11月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Effect of anodizing time on multiscale porous structure of Ti-Al alloy microchannel wall
    Tatsuya Ohmi, Tatsuki Yamamori, Masatoshi Sakairi
    Keikinzoku/Journal of Japan Institute of Light Metals, 67, 11, 589, 594, Japan Institute of Light Metals, 2017年, [査読有り]
    日本語, 研究論文(学術雑誌), Effect of anodizing time on the multiscale porous structure of the inner wall of the microchannel produced in a titanium alloy body has been investigated. The microchannel was produced by a powder-metallurgical process in which a titanium-powder compact containing thin aluminum wire was sintered at a temperature above the melting point of aluminum. During sintering, microscopic infiltration of molten aluminum into the porosity of the compacted titanium powder and subsequent diffusion of aluminum into the titanium powder particles brought about the formation of a microchannel lined with Ti-Al alloy layer in the sintered body. The inner walls of the microchannels with uniform composition, Ti-18.0(±1.8) mol%Al, were provided for anodizing experiments. When the anodizing time was in the range from 1.8 to 28.8 ks, the structure of the anodic oxide film was nanotube array. Each specimen had a microchannel of several hundred micrometers in diameter, inner wall asperity of several ten micrometers in size, and nanotube array structure of the anodic oxide film. In the specimen anodized for 59.6 ks, on the other hand, the nanotube array had changed to a different structure resembling that of nanoporous metals produced by dealloying.
  • Effect of Metal Cations in Fresh Water on Surface Film Structure and Initial Corrosion of Mild Steel
    K. Otani, M. Sakairi
    OXIDE FILMS: A SYMPOSIUM IN HONOR OF MASAHIRO SEO, 75, 27, 59, 64, ELECTROCHEMICAL SOC INC, 2017年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), Effect of metal cations on the corrosion of mild steel in model fresh water was investigated by immersion corrosion tests with surface observations, mass changes, and surface analysis by X-ray photoelectron spectroscopy (XPS). XPS analysis showed that hard metal cations precipitate on the mild steel and form hydroxides on the steel. The results of corrosion test suggested that corrosion rate of mild steel in fresh water has a correlation with protective ability of hydroxide layer precipitated on the steel. A novel corrosion indicator, that consists of hardness of cation, X, and molar volume ratio,Delta V, is proposed, and it is shown that the indicator is useful for explaining the corrosion changes by metal cations in fresh water.
  • Inhibition Ability of Gluconates for Fresh Water Corrosion of Mild Steel Enhanced by Metal Cations
    Kyohei Otani, Md. Saiful Islam, Masatoshi Sakairi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 164, 9, C498, C504, ELECTROCHEMICAL SOC INC, 2017年, [査読有り]
    英語, 研究論文(学術雑誌), Inhibition ability of gluconates for fresh water corrosion of mild steel changed with metal cations were investigated by immersion tests and electrochemical impedance spectroscopy (EIS) tests. The results of the tests showed that the inhibition ability of gluconates was enhanced by metal cations that have large "corrosion inhibitory effect of cation, Y", in model fresh water. Surface analysis showed that gluconate ligands and metal cations that have large Y can bond on mild steel and that they form a protective film on the steel. EIS analysis with an equivalent circuit suggested that metal cations that have large Y would reduce the area of defects in the protective film of gluconates. (C) 2017 The Electrochemical Society. All rights reserved.
  • Effects of metal cations on corrosion of mild steel in model fresh water
    Kyohei Otani, Masatoshi Sakairi
    CORROSION SCIENCE, 111, 302, 312, PERGAMON-ELSEVIER SCIENCE LTD, 2016年10月, [査読有り]
    英語, 研究論文(学術雑誌), The effects of metal cations on corrosion of mild steel in model fresh water were investigated by electrochemical techniques and immersion tests. Analysis of X-ray photoelectron spectroscopy showed that metal cations have large hardness of cations, X, are incorporated in passive films. The electrochemical and immersion results showed that Xis not suitable as a corrosion indicator of mild steel. A novel corrosion indicator, "corrosion inhibitory effect of cations Y '', that consists of X and molar volume ratio, Delta V, is proposed, and it is shown that the novel indicator can estimate the corrosion rate of mild steel in fresh water. (C) 2016 Elsevier Ltd. All rights reserved.
  • Formation of layered structure porous-type anodic alumina films locally with a solution flow-type micro-droplet cell
    Masatoshi Sakairi, Fumika Nishino, Regina Itzinger
    SURFACE AND INTERFACE ANALYSIS, 48, 8, 928, 932, WILEY-BLACKWELL, 2016年08月, [査読有り]
    英語, 研究論文(学術雑誌), A solution flow-type micro-droplet cellwith co-axial dual capillary tubes (Sf-MDC) was applied to formporous-type anodic alumina film with layered structure at selected areas on aluminum. The anodizing process with different repetition numbers, yielding different oxide layer numbers, was performed with the Sf-MDC. The investigation of cross sections of the formed oxide showed that the pore diameter widened at the boundary between layers. From a simulated anodizing process with the Sf-MDC, the reason for this modification of the pores was suggested to be intermittent anodizing with processes of drying up of the solution of the pores and widening at the bottom of the pores. Copyright (C) 2015 John Wiley & Sons, Ltd.
  • Formation of oxide films for high-capacitance aluminum electrolytic capacitor by liquid-phase deposition and anodizing
    Masatoshi Sakairi, Ryota Fujita, Shinji Nagata
    SURFACE AND INTERFACE ANALYSIS, 48, 8, 906, 912, WILEY-BLACKWELL, 2016年08月, [査読有り]
    英語, 研究論文(学術雑誌), Liquid-phase deposition (LPD) treatment and anodizing were used to form oxide layer for a high-capacitance aluminum electrolytic capacitor. Formation of protective oxide layers and modification of LPD conditions make it possible to prolong the LPD duration and lead to the formation of TiO2 and NaF deposits on aluminum. A titanium oxide/aluminum oxide mixed layer was formed by a combination process of LPD treatment and anodizing. The capacitance of the formed layer was about 300% higher than that of an anodic oxide film formed on electropolished aluminum. The structures and compositions of the films that were formed were determined by transmission electron microscopy, scanning electron microscopy, and Rutherford backscattering spectroscopy. Copyright (C) 2015 John Wiley & Sons, Ltd.
  • Effect of surface conditions and specimen composition on hydrogen permeation behavior of coated and uncoated steels during wet and dry corrosion at a constant dew point               
    K. Igarashi, M. Sakairi
    ISIJ International, 57, 466, 472, 2016年03月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Effect of Surface Conditions and Specimen Composition on Hydrogen Permeation Behavior of Coated and Uncoated Steels during Wet and Dry Corrosion at a Constant Dew Point
    Koya Igarashi, Masatoshi Sakairi
    ISIJ INTERNATIONAL, 56, 3, 465, 471, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2016年, [査読有り]
    英語, 研究論文(学術雑誌), A wet and dry corrosion test with a constant dew point was applied to investigate the effects of scratches and specimen composition on the hydrogen permeation behavior of Zn and 55 mass% Al-Zn coated steels as well as of uncoated steel. There was an etched size controlled scratch formed on specimens with a laser machining technique. The hydrogen permeation current was observed to be independent of the specimen composition and the area of the formed scratches, the corrosion products were observed after the tests. The hydrogen permeation current of the steels with the formed scratches decreased with number of cycles of the wet and dry tests. Except in the first cycle there were no significant changes in the current with cycle number on steels without formed scratches. It was suggested that the composition, scratch, and corrosion products play an important role in the hydrogen permeation behavior during wet and dry corrosion.
  • Effect of a Kind of Metal Cation on Corrosion Mechanism of A3003 Aluminum Alloy in Tap Water
    Kyohei Otani, Masatoshi Sakairi, Akira Kaneko
    MATERIALS TRANSACTIONS, 57, 9, 1539, 1546, JAPAN INST METALS, 2016年, [査読有り]
    英語, 研究論文(学術雑誌), Effect of a kind of metal cation on corrosion mechanism of A3003 aluminum alloy in tap water was investigated by electrochemical techniques and immersion corrosion tests. Corrosion rate of the aluminum alloy decreased with increase in a hardness of cation, except for Mg2+. XPS analyses showed metal cations, classified as a hard acid in tap water were incorporated in hydroxides on the aluminum alloy. The results suggest that the incorporated cations have corrosion inhibitory effect (e.g., Ca2+ and Zn2+) or corrosion promotive effect (e.g., Mg2+). These different effects can be explained by difference in molar volume between hard metal cation's hydroxide and aluminum hydroxide.
  • hanges in oxide film structure of aluminum alloy by incorporation of cations in tap water               
    K. Otani, M. Sakairi, A. Kaneko
    Material Transaction, 57, 1539, 1546, 2016年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Improvement of Corrosion Resistance of Aluminum Alloy with Wettability Controlled Porous Oxide Films               
    M. Sakairi, V. Goyal
    Corrosion Science and Technology, 15, 166, 170, 2016年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Development of an Area-selective Technique for Electrochemical Hydrogen Detection with Laser Local Activation
    Masatoshi Sakairi, Koya Igarashi, Akihide Nagao
    ISIJ INTERNATIONAL, 56, 3, 483, 486, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2016年, [査読有り]
    英語, 研究論文(学術雑誌), An area-selective technique for electrochemical hydrogen detection with laser local activation (focused pulse YAG laser irradiation) has been newly developed. The developed technique was applied to measure hydrogen permeation behavior of iron at selected areas of various grain structures. The hydrogen permeation current was detected after the laser irradiation, suggesting that indirect activations of hydrogen generation and entry reactions were produced by the focused pulse YAG laser irradiation, which activated dissolution of metals at the irradiated areas. An obtained hydrogen diffusion coefficient, D-H, was in good agreement with previously reported D-H of iron, while a clear dependence of D-H on grain structure at the entry side was not found.
  • Effect of Surface Conditions and Relative Humidity on Hydrogen Permeation Behavior of Zinc Coated Steels during Wet and Dry Corrosion
    Masatoshi Sakairi, Shogo Takagi
    ISIJ INTERNATIONAL, 56, 3, 452, 458, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2016年, [査読有り]
    英語, 研究論文(学術雑誌), The effects of scratch, surface element composition, and relative humidity on the hydrogen permeation behavior of zinc coated steels during wet and dry cycle corrosion tests were investigated. The permeating hydrogen was measured electrochemically, and a size controlled scratch was formed on zinc coated steels with a laser machining technique. The hydrogen permeation current was observed on the zinc coated steels with a formed scratch (S-coated): no significant hydrogen permeation current was observed on the zinc coated steel without the formed scratch (NS-coated) or on steel with zinc coating removed by mechanical grinding (R-steel). The zinc corrosion products effectively reduced the hydrogen permeation current from the S-coated at low relative humidity. The total amount of permeating hydrogen per unit area of formed scratch was independent of the area of the formed scratch in wet and dry cycling.
  • Corrosion degradation of AISI type 304L stainless steel for application in nuclear reprocessing plant
    S. Ningshen, M. Sakairi
    JOURNAL OF SOLID STATE ELECTROCHEMISTRY, 19, 12, 3533, 3542, SPRINGER, 2015年12月, [査読有り]
    英語, 研究論文(学術雑誌), The degradation of materials involving corrosion in handling nitric acid in the spent fuel nuclear reprocessing plant is a serious issue. In the present work, the corrosion resistance of American Iron and Steel Institute (AISI) type 304L stainless steel (SS) and nitric acid grade (NAG) type 310L SS in 1 to 11.5 M HNO3 and boiling 15.65 M HNO3 was evaluated. In both the alloy steels, the open circuit potential and corrosion potential are shifted to more noble potential with increasing concentrations. However, the passive current density was not affected, and the transpassive potential was shifted to higher potential with increasing concentrations. The corrosion rate measured in boiling 15.65 M HNO3 after 240 h shows a much lower corrosion rate in type 310L SS (similar to 0.06 +/- A 0.012 mm/y) then type 304L SS (similar to 0.18 +/- A 0.02-0.2 +/- A 0.001 mm/y). These observations are corroborated with the scanning electron microscope (SEM) morphologies that show severe intergranular corrosion (IGC) attack in type 304L SS then in type 310L SS. The X-ray photoelectron spectroscopy (XPS) study of the passive oxide films of both alloy steels shows the presence of Cr2O3 and SiO2, and the depth profile indicated predominant Si enrichment.
  • Corrosion performance and surface analysis of Ti-Ni-Pd-Ru-Cr alloy in nitric acid solution
    S. Ningshen, M. Sakairi, K. Suzuki, T. Okuno
    CORROSION SCIENCE, 91, 120, 128, PERGAMON-ELSEVIER SCIENCE LTD, 2015年02月, [査読有り]
    英語, 研究論文(学術雑誌), The corrosion resistance of Ti-0.4Ni-0.015Pd-0.025Ru-0.14Cr (AKOT Ti) and commercially pure titanium (CP Ti) has been studied in different concentrations of 6, 9 and 11.5 M HNO3, and boiling 15.65 M In both CP Ti and AKOT Ti alloy, the open circuit potential and corrosion potential are shifted to more noble potential with increasing concentrations. However, passive current density decreases with increasing concentration. Lower corrosion rate was observed in AKOT Ti (similar to 0.075 mm/y) compared to CP Ti (similar to 0.22 mm/y) in boiling 15.65 M HNO3 after 240 h. The mechanisms by which dissolved titanium ions affect the corrosion are also discussed. (C) 2014 Elsevier Ltd. All rights reserved.
  • Surface analysis of passive films formed on Aluminum alloys in different metal cation containing solutions               
    M. Sakairi, R. Sasaki, K. Otani, K. Suzuki, A. Kaneko
    European Corrosion Congress, EUROCORR 2015, 3, 1527, 1530, Austrian Society for Metallurgy and Materials (ASMET), 2015年
    英語, 研究論文(国際会議プロシーディングス), The effect of metal cations on the characteristics of passive films formed on aluminum alloys during immersion in neutral solutions with different metal cations was investigated. The surface observation showed that surface morphology was strongly affected by the kind of metal cations. The XPS analysis showed that the thickness of the passive film formed on A3003 was thinner than that on A5052, and hard metal cations were incorporated into the passive films.
  • Evaluation of metal cation effects on galvanic corrosion behavior of the A5052 aluminum alloy in low chloride ion containing solutions by electrochemical noise impedance
    M. Sakairi, R. Sasaki, A. Kaneko, Y. Seki, D. Nagasawa
    ELECTROCHIMICA ACTA, 131, 123, 129, PERGAMON-ELSEVIER SCIENCE LTD, 2014年06月, [査読有り]
    英語, 研究論文(学術雑誌), The effects of metal cations on the galvanic corrosion behavior of the A5052 aluminum alloy in low chloride ion containing solutions (tap water) were examined by electrochemical noise impedance. The electrochemical noise impedance and conductance were calculated by the power spectral density (PSD) of the galvanic current and potential. The oscillations in the galvanic current correlate well with the oscillations in the potential. The total charge (summation of galvanic current) during galvanic corrosion tests was suppressed by the addition of Ca2+, while it was increased with Mg2+ addition. Only a small effect on mean impedance and conductance was observed in solutions with Cu2+ and Mg2+, while addition of Ca2+ strongly influences both the mean impedance and conductance. These results may be explained by the passive film structure changes due to the metal cations. The results obtained in this study indicate that metal cations play a very important role in the corrosion behavior of A5052 aluminum alloys in tap water. (C) 2014 Elsevier Ltd. All rights reserved.
  • The surface characterization and corrosion resistance of 11 % Cr ferritic/martensitic and 9-15 % Cr ODS steels for nuclear fuel reprocessing application
    S. Ningshen, M. Sakairi, K. Suzuki, S. Ukai
    JOURNAL OF SOLID STATE ELECTROCHEMISTRY, 18, 2, 411, 425, SPRINGER, 2014年02月, [査読有り]
    英語, 研究論文(学術雑誌), In spent fuel nuclear reprocessing plant, nitric acid is the main medium used in PUREX method. The passive film compositions and corrosion resistance of 11 % Cr ferritic/martensitic and 9-15 % Cr oxide dispersion strengthened steels in different nitric acid concentrations were studied. The open circuit potential is shifted toward more noble potential as the concentrations increased from 1 M HNO3 to 9 M HNO3 in all the investigated alloy steels. The results of the potentiodynamic polarization plots also exhibited a shift in corrosion potential as the concentrations increased from 1 M to 9 M HNO3. This shift is undesirable because of risk of overshooting the potential beyond passive region and may result into transpassive corrosion. The X-ray photoelectron spectroscopy results of the passive film analysis are composed mostly of Fe2O3, Cr2O3, and Y2O3, and the depth profile of Fe and Cr concentrations vary depending upon the nitric acid concentration. The surface morphology after the corrosion test does not show intergranular corrosion attack at the nitric acid concentrations studied. It is desirable that materials for use in nitric acid service are resistant to such corrosion induced degradation.
  • The effects of film thickness and incorporated anions on pitting corrosion of aluminum with barrier-type oxide films formed in neutral borate and phosphate electrolytes
    Hiroki Habazaki, Rokuro Nishimura, Kenji Okitsu, Hiroyuki Inoue, Ikuo Kiriyama, Fumitaka Kataoka, Masatoshi Sakairi, Hideaki Takahashi
    JOURNAL OF SOLID STATE ELECTROCHEMISTRY, 18, 2, 369, 376, SPRINGER, 2014年02月, [査読有り]
    英語, 研究論文(学術雑誌), The pitting corrosion behavior of high-purity aluminum covered with barrier-type anodic films, which are formed in neutral borate and phosphate electrolytes, has been examined in 0.5 mol dm(-3) NaCl solution at an applied potential of -0.6 V versus Ag/AgCl, which is slightly nobler than the pitting potential of -0.64 V in the same solution. The pitting current density, i (p), increased with time after an incubation time, t (i). The double logarithmic plot of i (p) and polarization time, t, reveal two straight lines, which are separated at the time, tau. The slope becomes larger after tau for the specimens anodized in the phosphate electrolyte, while it becomes smaller for those in the borate electrolyte. Both the t (i) and tau increase with the thickness of the anodic films, and at the similar film thickness, they are much larger for the anodic films formed in the phosphate electrolyte than for those in the borate electrolyte. The corrosion process can be divided into three stages: the incubation period up to t (i), the pit nucleation period before tau, and the pit growth period after tau. We have discussed the different pitting corrosion behavior of the aluminum specimens covered with the anodic films formed in the borate and phosphate electrolytes in terms of ion selectivity of the anodic films.
  • Effect of metal cations on corrosion behavior and surface film structure of the A3003 aluminum alloy in model tap waters
    K. Otani, M. Sakairi, R. Sasaki, A. Kaneko, Y. Seki, D. Nagasawa
    JOURNAL OF SOLID STATE ELECTROCHEMISTRY, 18, 2, 325, 332, SPRINGER, 2014年02月, [査読有り]
    英語, 研究論文(学術雑誌), The effect of the metal cations, Na+, K+, Ca2+, Mg2+, Zn2+, and Ni2+, on the oxide film structure and morphology changes during long-term immersion corrosion tests of aluminum alloy (A3003) in model tap waters was investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy. The effect of the metal cations on the corrosion behavior was also investigated with mass change and electrochemical tests. The hardness of the metal cations, X, based on the hard and soft acids and bases (HSAB) concept was applied to explain the effect of metal cations on the passive oxide film structure and corrosion resistance. The mass change rate and corrosion current density decreased with increasing metal cation hardness. The XPS results showed that hard metal cations like Zn2+ and Ni2+ were incorporated in the oxide films, while the four soft metal cations were not incorporated in the oxide films. The results are in good agreement with those which could be expected from the HSAB hardness of the metal cations.
  • Electrochemical Noise Evaluation of Metal Cation Effects on Galvanic Corrosion of Aluminum Alloys in Low Concentration of Chloride Ion Containing Solutions
    M. Sakairi, K. Otani, R. Sasaki
    STRUCTURAL INTEGRITY, 86, 589, 596, ELSEVIER SCIENCE BV, 2014年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), The effect of metal cations on the galvanic corrosion behavior of A3003 aluminum alloy in low concentration of chloride ion containing solutions (tap waters) was examined by electrochemical noise impedance. The electrochemical noise impedance and conductance were calculated by the power spectrum density of the galvanic current and potential. The sum of the galvanic current during galvanic corrosion tests was suppressed by the addition of Ca2+, Zn2+ and Ni2+, while it was increased with Mg2+ addition. These results may be explained by the passive film structure changes due to the metal cations. The results obtained in this study indicate that metal cations play an important role in the corrosion behavior of A3003 aluminum alloys in tap water. (C) 2014 The Authors. Published by Elsevier Ltd.
  • 被覆した白金線対極を用いる溶液フロー型微小液滴セルによるアルミニウムの局部陽極酸化               
    山口智也, 坂入正敏
    表面技術, 65, 385, 390, 2014年, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Nanostructured anodic-alumina-based dielectrics for high-frequency integral capacitors
    Alexander Mozalev, Masatoshi Sakairi, Hideaki Takahashi, Hiroki Habazaki, Jaromir Hubalek
    THIN SOLID FILMS, 550, 486, 494, ELSEVIER SCIENCE SA, 2014年01月, [査読有り]
    英語, 研究論文(学術雑誌), Three types of thin solid films with the nanoscale inner structures were synthesized by sputtering-deposition and anodizing of Al layer, Al-1.5 at.% Si alloy layer, and Al/Ta bilayer on Si wafers. All the anodic films comprised 1 mu m thick nanoporous alumina layer as the key component. The essential differences were due to the silicon impurities (AlSi alloy) and the array of nanosized tantalum oxide protrusions in the alumina barrier layer (Al/Ta bilayer). The films were examined by scanning and transmission electron microscopy and electrochemical impedance spectroscopy. Integral capacitors utilizing the anodic films as dielectrics combine the small-value capacitance (6.5 nF cm(-2)) with the excellent properties of high withstand field strength (1.7-2.7 MV cm(-1)), low leakage current ((3-20) x 10(-12) A mm(-2) at 1.0 MV cm(-1)), and low loss tangent (tg delta = (4-6) x 10(-3)). The revealed dispersion of dielectric constant, although within 10%, and the presence of loss peaks on the temperature and frequency dependencies of tgd denote the influence of ion-relaxation mechanism on dielectrics' polarizability, with the characteristic times ranging from 10 to 145 mu s depending on the dielectric type. By selecting appropriate technological and electrolytic conditions, the functionality of the capacitors can be optimized to meet the needs of a specific range, from 1 kHz to about 300 MHz operating frequencies. (C) 2012 Elsevier B. V. All rights reserved.
  • The corrosion resistance and passive film compositions of 12% Cr and. 15% Cr oxide dispersion strengthened steels in nitric acid media
    S. Ningshen, M. Sakairi, K. Suzuki, S. Ukai
    CORROSION SCIENCE, 78, 322, 334, PERGAMON-ELSEVIER SCIENCE LTD, 2014年01月, [査読有り]
    英語, 研究論文(学術雑誌), The passive film compositions and corrosion resistance of 12% Cr and 15% Cr oxide dispersion strengthened (ODS) steels in 3 M HNO3 to 9 M HNO3 was evaluated. The potentiodynamic polarization plots exhibited a shift in corrosion potential, and higher passive current density with increasing HNO3 concentrations. In 12% Cr ODS. steel, high corrosion rate was observed in all HNO3 concentrations. However, low corrosion rate observed in 15% Cr ODS steel was attributed to Al2O3 enrichment. The TEM analysis indicated a complex Y2Hf2O7 formation in 15% Cr ODS steel, and this may have a role in suppressing intergranular corrosion attack. 2013 Elsevier Ltd. All rights reserved.
  • The effects of the coating of anodized titanium with multi-walled carbon nanotuves on bone formation.
    Inoue S, Uo M, Sakairi M, Hirata E, Lee M.H, Bae T.S, Akasaka T, Watari F, Yokoyama A
    Key Engineering Materials, 529-530, 621, 624, TRANS TECH PUBLICATIONS LTD, 2013年11月, [査読有り]
    英語, 研究論文(学術雑誌), Carbon nanotubes (CNTs) have excellent chemical, physical, and biological properties such as strong cell adhesion, protein adsorption and cell proliferation in vitro. Excellent osteocompatibility for the CNT monolith was also reported in vivo. The purpose of this study was to evaluate the effects of anodized titanium coated with multiwalled CNTs (MWCNTs) on human osteosarcoma Saos2 cells and bone tissue. Saos2 cells on CNT-Ti showed excellent proliferation with extension of cell morphology in all directions. CNT-Ti wire was implanted in the bone marrow of femurs of rats. At 2 weeks after surgery, histological investigations revealed that bone tissue attached to the surface of the CNT-Ti directly. Thus the surface modification of anodized Ti by MWCNTs can be effective for bone formation.
  • Aluminum bulk micromachining through an anodic oxide mask by electrochemical etching in an acetic acid/perchloric acid solution
    Tatsuya Kikuchi, Yuhta Wachi, Masatoshi Sakairi, Ryosuke O. Suzuki
    MICROELECTRONIC ENGINEERING, 111, 14, 20, ELSEVIER SCIENCE BV, 2013年11月, [査読有り]
    英語, 研究論文(学術雑誌), A well-defined microstructure with microchannels and a microchamber was fabricated on an aluminum plate by four steps of a new aluminum bulk micromachining process: anodizing, laser irradiation, electrochemical etching, and ultrasonication. An aluminum specimen was anodized in an oxalic acid solution to form a porous anodic oxide film. The anodized aluminum specimen was irradiated with a pulsed Nd-YAG laser to locally remove the anodic oxide film, and then the exposed aluminum substrate was selectively dissolved by electrochemical etching in an acetic acid/perchloric acid solution. The anodic oxide film showed good insulating properties as a resist mask during electrochemical etching in the solution. A hemicylindrical microgroove with thin free-standing anodic oxide on the groove was fabricated by electrochemical etching, and the groove showed a smooth surface with a calculated mean roughness of 0.2-0.3 mu m. The free-standing oxides formed by electrochemical etching were easily removed from the specimen by ultrasonication in an ethanol solution. Microchannels 60 mu m in diameter and 25 mu m in depth connected to a microchamber were successfully fabricated on the aluminum. (C) 2013 Elsevier B.V. All rights reserved.
  • Analysis of chemical compositions and morphology of surface films formed on 3003 aluminum alloy by immersion in different cation containing model tap waters
    M. Sakairi, K. Otani, A. Kaneko, Y. Seki, D. Nagasawa
    SURFACE AND INTERFACE ANALYSIS, 45, 10, 1517, 1521, WILEY-BLACKWELL, 2013年10月, [査読有り]
    英語, 研究論文(学術雑誌), The effect of metal cations, Na+, K+, Ca2+, Mg2+, Zn2+, and Ni2+, on oxide film structure and morphology changes during immersion corrosion tests of 3003 aluminum alloy in model tap waters was investigated by surface analysis techniques including Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. The hardness of metal cations based on the hard and soft acids and bases (HSAB) concept was applied to explain the effect on the passive oxide film structure. Numerous nano-sized pits were observed after 86.4 ks immersion in model tap water, and nano-sized corrosion products were also observed especially in specimens immersed in K+ containing solutions. The AES and XPS results showed that hard metal cations like Zn2+ and Ni (2+) were included in the oxide films, while soft metal cations were not included in the oxide films. The results are in good agreement with those which could be expected from the HSAB hardness of the metal cations. Copyright (c) 2013 John Wiley & Sons, Ltd.
  • Formation of alumina films with nano-dot structures by successive liquid phase deposition, anodizing, and substrate dissolution
    M. Sakairi, R. Fujita, H. Jha, T. Kikuchi
    SURFACE AND INTERFACE ANALYSIS, 45, 10, 1510, 1516, WILEY-BLACKWELL, 2013年10月, [査読有り]
    英語, 研究論文(学術雑誌), A process based on successive anodizing, liquid phase deposition (LPD), re-anodizing, and aluminium substrate dissolution to form alumina films with nano-dot structures is demonstrated. Initially, a protective oxide film is formed on the aluminium surface to prevent further dissolution of the aluminium substrate during LPD processing. Because of heterogeneity in the protective oxide film, localized dissolution would otherwise occur under the film, resulting in pit formation during the LPD treatment. During re-anodizing, these pits act as a mold for anodic oxide resembling a nano-dot like structure. Optimization of LPD parameters, such as time and temperature, would make it possible to obtain alumina films with nano-dot structures with sizes smaller than 1 mu m. Alumina films with nano-dot structures with hollow can be realized by controlling the LPD conditions. Copyright (c) 2013 John Wiley & Sons, Ltd.
  • Corrosion Resistance of 9% Cr Oxide Dispersion-Strengthened Steel in Different Electrolytic Media
    S. Ningshen, M. Sakairi, K. Suzuki, S. Ukai
    CORROSION, 69, 9, 863, 874, NATL ASSOC CORROSION ENG, 2013年09月, [査読有り]
    英語, 研究論文(学術雑誌), The corrosion resistance and passive film compositions of 9% Cr oxide dispersion-strengthened steel in different acidified and chloride media was evaluated. The results presented below show that with increasing concentrations of 1 M to 11.5 M nitric acid (HNO3), the open-circuit potential reveals a more noble potential, while in chloride-containing media, a less noble potential was observed. The potentiodynamic polarization plots exhibited higher breakdown/transpassive potentials in acidic media with 0.5 M sulfuric acid (H2SO4) and 1 M to 11.5 M HNO3, and there was a shift in the corrosion potential toward the transpassive region as the HNO3 concentration increased from 1 M to 11.5 M. However, no intergranular corrosion attack was observed at the HNO3 concentrations studied. In acidic-chloride media (0.5 M H2SO4 with 0.1 M and 0.5 M sodium chloride [NaCl]) and in chloride only media (0.1 M NaCl and 0.5 M NaCl) poor pitting corrosion resistance was attributable to the microstructural inhomogeneity and inclusions in the steel. The x-ray photoelectron spectroscopy analysis indicated that the passive film has iron(III) oxide (Fe2O3) and chromium(III) oxide (Cr2O3), along with yttrium oxide (Y2O3). The scanning electron microscopy (SEM) examinations showed that the pits on the specimen were hemispherical and formed lace-like patterns. The corrosion properties affected by the dispersed oxide are also discussed in the paper.
  • The passive film characterization and anodic polarization behavior of 11% Cr ferritic/martensitic and 15% Cr oxide dispersion strengthened steels in different electrolytic solutions
    S. Ningshen, M. Sakairi, K. Suzuki, S. Ukai
    APPLIED SURFACE SCIENCE, 274, 345, 355, ELSEVIER SCIENCE BV, 2013年06月, [査読有り]
    英語, 研究論文(学術雑誌), The ferritic/martensitic (F/M) and oxide dispersion strengthened (ODS) steels are the most promising candidate materials for future nuclear power plants. In the present work, the passive film compositions and its correlation with anodic polarization behavior of 11% Cr F/M and 15% Cr ODS steels was examined in different electrolytic solutions of borate buffer, acidic, acidified chloride and in chloride solution. The X-ray photoelectron spectroscopy analysis of the passive film reveals the existence of the layers of Cr2O3 and Fe2O3 and in 15% Cr ODS steel along with Y2O3. The open circuit potential and potentiodynamic anodic polarization measurements show that pitting corrosion resistance is strongly dependent on electrolytic solutions and passive film compositions. The ODS steel indicated increased breakdown potential and wider passive range as compared to F/M steel in chloride containing media. In a non-chloride environment, this difference is not prominent. However, low pitting corrosion resistance of both steels in chloride solutions was attributable to Cl- and microstructural inhomogeneity. The SEM micrographs of surface morphology of corrosion attack showed severe pitting corrosion attack in chloride solutions. The anodic polarization behavior of F/M and ODS steels in different electrolytic solutions was studied for this work in relation to passive film compositions. (C) 2013 Elsevier B.V. All rights reserved.
  • Fabrication of a meniscus microlens array made of anodic alumina by laser irradiation and electrochemical techniques
    Tatsuya Kikuchi, Yuhta Wachi, Taka-aki Takahashi, Masatoshi Sakairi, Ryosuke O. Suzuki
    ELECTROCHIMICA ACTA, 94, 269, 276, PERGAMON-ELSEVIER SCIENCE LTD, 2013年04月, [査読有り]
    英語, 研究論文(学術雑誌), An anodic alumina microlens array was fabricated by laser irradiation and electrochemical techniques. An aluminum specimen covered with a porous oxide film was irradiated with a pulsed Nd-YAG laser, and then electropolished to dissolve the aluminum substrate. A well-defined semi-elliptical micropore was formed on the aluminum by electropolishing. The immersion of the electropolished specimen in a CrO3/H3PO4 solution resulted in the dissolution of the remaining anodic oxide film. Subsequent re-anodizing enabled the formation of a characteristic meniscus-shaped oxide film on the micropore. A microlens array made of the thin anodic alumina film, which showed flexibility and heat resistance, was successfully fabricated by the lift-off of the anodic oxide. (C) 2013 Elsevier Ltd. All rights reserved.
  • Formation of Nanoporous structures on planner Al-Zn Alloy Lining Layers by Anodic Oxidation               
    M. Ishida, T. Ohmi, M. Sakairi, M. Igugchi
    Journal of JSEM, 13, S205, S208, 2013年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Effects of alkali leaching on composition and surface structure of Cu-Al alloy layer produced by powder-metallurgical method,               
    A. Maruyama, T. Ohmi, M. Sakairi, M. Iguchi
    Journal of JSEM, 13, S193, D198, 2013年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Corrosion resistance of 9-15% Cr ODS steels and its comparison with austenitic stainless steel
    S. Ningshen, M. Sakairi, K. Suzuki, S. Ukai
    CENTURY OF STAINLESS STEELS, 794, 575, +, TRANS TECH PUBLICATIONS LTD, 2013年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), An oxide dispersion strengthened steels are one of the mast promising high temperatures, and high performance advanced structural material being developed for future fast reactors-and high-temperature Generation IV reactors. In the present work, the corrosion resistance and its correlation with the passive film compositions of 11% Cr F/M and 9-15% Cr (with Zr or Hf) ODS steels is examined and compared with AISI type 304L stainless steel in boiling 60 - 62% (similar to 13 M) HNO3. The corrosion rate measured in 62% HNO3 for 240 h of 11% Cr F/M, 9% Cr and 15% Cr (Zr) ODS steels show high corrosion rate. On the other hand, low corrosion rate was observed in 304L stainless steel (0. 21 to 23 mm y(-1)). However, severe intergranular corrosion attack was revealed in type 304L SS after 240 h exposure, but none in ODS steels. Such an intergranular corrosion attack seen in type 304L stainless steel is undesirable. On the contrary, low corrosion rate (0.04 - 0.15 mm y(-1)) of 15% Cr (Hf) ODS steel in 3 M, 6 M and 9 M HNO3, comparable to that of type 304L stainless steel was observed. The improved corrosion resistance of 15% Cr (Hf) ODS steel was attributed to enrich (20 at. %) and protective Al2O3 layer formation in addition to Cr2O3 in the passive film.
  • Structure control of Cu-Zn microchannel lining layers with electrochemical dissolution
    K. Kobayashi, T. Ohmi, T. Kumagai, M. Sakairi, M. Iguchi
    Journal of JSEM, 12, s213, s216, The Japanese Society for Experimental Mechanics, 2012年09月, [査読有り]
    英語, 研究論文(学術雑誌), The effect of potentiostatic dissolution on the structure of a Cu-Zn alloy microchannel lining layer was investigated. The microchannel lining layer was fabricated by a powder-metallurgical process using copper powder and zinc wire. The lining layer became more porous after potentiostatic dissolution at a constant potential of −0.5 V vs. Ag/AgCl. The lining layer was remarkably dezinced and it contained many open pores under the dissolution condition at +0.5 V. These results indicate the possibility of precise structure control of the microchannel lining layer.
  • Composition and structure changes in Al3Ni2 microchannel lining layers by alkali leaching
    Y. Saitoh, T. Ohmi, M. Sakairi, T. Kumagai, M. Iguchi
    Journal of JSEM, 12, s237, s242, The Japanese Society for Experimental Mechanics, 2012年09月, [査読有り]
    英語, 研究論文(学術雑誌), Effects of alkali leaching time on the composition and structure changes in the Al3Ni2 microchannel lining layer produced by a sacrificial-core method have been investigated. The composition was measured both on the specimen surface directly exposed to the leachant and on the new surface cut after alkali leaching. In each surface, the decrease in Al concentration became sluggish after formation of Ni3Al. On the other hand, nano structure consisted of almost pure Ni was detected on the inner wall of the microchannel leached for 864 ks.
  • Influence of desiccation procedures on the surface wettability and corrosion resistance of porous aluminium anodic oxide films
    Meng Zheng, Masatoshi Sakairi, Himendra Jha
    CORROSION SCIENCE, 55, 332, 338, PERGAMON-ELSEVIER SCIENCE LTD, 2012年02月, [査読有り]
    英語, 研究論文(学術雑誌), A hydrophobic oxide film was formed on aluminium by anodizing followed by desiccation treatment. Films subjected to gradual heating and cooling exhibit larger water contact angles than samples exposed to fast heating and cooling at the same temperature. From SEM and Auger Electron Spectroscopic observations, the low wettability surface shows a regular porous morphology with no significant chemical composition differences due to the different treatments. The desiccation process improves the corrosion resistance, shown by immersion in NaCl. The change in morphology by the desiccation processes is considered a main reason to lower the wettability, which further affects the corrosion properties. (C) 2011 Elsevier Ltd. All rights reserved.
  • nodic oxidation behavior of Al-Zn alloy lining layer produced by a sacrificial-core method
    M. Ishida, T. Ohmi, M. Sakairi, M. Iguhchi
    Journal of JSEM, 12, s222, s225, The Japanese Society for Experimental Mechanics, 2012年, [査読有り]
    英語, 研究論文(学術雑誌), We investigated the influence of Zn on anodic oxidation of planner Al-Zn lining layers produced by a sacrificial-core method. The Al-Zn lining layer was produced from aluminum powder and zinc plate. By comparison with experiments using sintered aluminum powder compacts, it was found that zinc hindered the formation of nanoporous alumina film. The nanoporous structure can be formed on the surface of the Al-Zn alloy lining layer by long time anodic oxidation of 7.2 ks.
  • Nonostructure anodic-alumina-based dielectrics for high-frequency integral capacitors               
    A. Mozalev, M. Sakairi, H. Takahashi, H. Habazaki, J. Hubalek
    Thin Solid Films, 2012年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Structure Control of Cu-Zn Microchannel Lining Layers with Potentiostatic Dissolution               
    Kazuki KOBAYASHI, Tatsuya OHMI, Masatoshi SAKAIRI, Manabu IGUCHI
    Proc. 6th International Symposium on Advanced Science and Technology in Experimental Mechanics, [1/1(CD-ROM)], 037, 2011年11月, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • 溶液フロー型液滴セルによる樹脂上への局部銅めっきと金属構造体の作製
    坂入 正敏, 後藤 良仁, 菊地 竜也, 伏見 公志
    表面技術 = The journal of the Surface Finishing Society of Japan, 62, 10, 511, 515, 表面技術協会, 2011年10月, [査読有り]
    日本語, A solution flow type microdroplet cell was applied to form a local copper line on a non-conductive substrate such as epoxy resin. During copper deposition, a copper rod was mounted in the epoxy resin as an electric feeding point. Such a copper line, which can be formed on the epoxy resin on flat and curved surfaces, can be removed from the epoxy resin, suggesting that this technique is applicable to form metal microstructures. The influence of the stage moving speed and applied current on the copper line thickness, shape, and conductivity were also investigated.
  • Corrosion resistant TiO2 film formed on magnesium by liquid phase deposition treatment
    R. Fujita, M. Sakairi, T. Kikuchi, S. Nagata
    ELECTROCHIMICA ACTA, 56, 20, 7180, 7188, PERGAMON-ELSEVIER SCIENCE LTD, 2011年08月, [査読有り]
    英語, 研究論文(学術雑誌), Liquid phase deposition treatment (LPD) was applied to form a corrosion protective titanium dioxide (TiO2) film on commercially available pure magnesium. Changing the solution pH, from acidic to highly alkaline, and with the addition of sucrose, it becomes possible to form a highly adhesive and thin TiO2 film on commercially available pure magnesium without any heat treatment. The role of the sucrose may be attributed to the formation of tetrafluoroboric acid (BF4)(-) in the solution reducing the homogeneous nucleation of TiO2 in the LPD solution. The film formed in the weak alkaline environment shows better corrosion resistance than at other LPD conditions, while the average rest potential is the same as that of as-polished specimens. This low rest potential may be due to micro-cracks in the formed film and high activity of the magnesium substrate. (C) 2011 Elsevier Ltd. All rights reserved.
  • 水素急増合金と空気熱交換式容器を用いた住宅・自立電源用抵コスト水素彫像システムに関する研究ー第3報パッシブ型水素貯蔵システムの住宅用燃料電池コージェネレーションシステムへの導入分析
    白土博康, 濱田靖弘, 須田孝徳, 坂入正敏, 岡 喜秋, 林宏樹, 池田英明, 長野克則
    空気調和・衛生工学会論文集, 171, 6, 1, 7, 公益社団法人 空気調和・衛生工学会, 2011年06月, [査読有り]
    日本語, 研究論文(学術雑誌), 本論文は,水素吸蔵合金と空気熱交換式容器を用いた水素貯蔵システムに関する一連の研究の第3報であり,改質器で生成した水素を貯蔵・供給し,燃料電池コージェネレーションの起動エネルギー,負荷追従エネルギーを削減するパッシブ型水素貯蔵システムの省エネルギー効果と電力負荷追従用としての導入可能性の評価を行ったものである.まず,戸建て住宅に本システムを導入した場合,一次エネルギー削減効果が向上することを示した.また,水素貯蔵システムの必要合金量は数kgから最大でも15kg程度で,エネルギー密度,耐久性,イニシャルコストの面でも蓄電池と比較して有効であり,住宅コージェネレーションシステム用として導入可能性が高いことが示唆された.
  • Influence of cations on the corrosion behaviour of aluminium alloys in drinking water and model tap water               
    M. Sakairi, Y. Kaneko, K. Otani, Y. Seki, D. Nagasawa
    18th International Corrosion Congress 2011, 3, 1841, 1850, 2011年
    英語, 研究論文(国際会議プロシーディングス), The corrosion behaviour of aluminium alloys in small amounts of chloride ions containing solutions was examined by focusing on the effect of added cations and solution pH (buffer reaction of added 0.5 kmol/m 3 H 3BO 3/0.05 kmol/m 3 Na 2B 4O 7). The effect of Cu deposition on corrosion behaviour of aluminium alloys was also investigated. The 3003 aluminium alloy shows lower corrosion resistance than 5005 aluminium alloy in the tap water and model tap waters. Corrosion of aluminium alloys is accelerated by addition of Ca 2+ ions to the model tap waters especially at low pH. This behaviour may be explained by H + concentration increases caused by CaCO 3 formation. Without Cl- ions, Cu 2+ ions do not increase the corrosion rate of the aluminium alloys.
  • Repassivation behavior of titanium in artificial saliva investigated with a photon rupture method
    Masatoshi Sakairi, Misaki Kinjyo, Tatsuya Kikuchi
    ELECTROCHIMICA ACTA, 56, 4, 1786, 1791, PERGAMON-ELSEVIER SCIENCE LTD, 2011年01月, [査読有り]
    英語, 研究論文(学術雑誌), Repassivation kinetics of titanium were investigated in artificial saliva by the photon rupture method, PRM, combined with anodizing. PRM uses focused pulsed Nd-YAG laser beam irradiation to remove oxide film and metal. The effects of the applied potential and F(-) ions on the repassivation kinetics of titanium were examined electrochemically. All conditions in this study use specimens that were repassivated within about 100 ms after the laser beam irradiation. The current transients after the laser beam irradiation showed a rapid increase, followed by a decrease with a slope of the log i vs. log t plots of about -1.5. The measured slope is steeper than what would be expected with the high field oxide film formation theory. This result suggests that the oxidation of titanium takes place through a combination of electrochemical and chemical reactions. More NaF results in a higher peak current density and amount of charge after laser beam irradiation. The influence of F- ions on the repassivation kinetics may be explained by localized pH changes caused by dissolution of titanium immediately after the laser beam irradiation. (C) 2010 Elsevier Ltd. All rights reserved.
  • SCC mechanism near fusion line of low c-13%cr welded joints
    Shuji Hashizume, Toshiya Nakayama, Masatoshi Sakairi, Koji Fushimi
    Zairyo to Kankyo/ Corrosion Engineering, 60, 4, 196, 201, 2011年, [査読有り]
    日本語, 研究論文(学術雑誌), Low Carbon-13%Cr martensitic stainless steels have been widely used for line pipe application because of their high strength and excellent corrosion resistance in corrosive conditions. Recently, both laboratory and field experiences related to cracking near fusion line of these steels weld joints in hot acid environments have been published. In this paper, SCC (Stress Corrosion Cracking) mechanism near fusion line of low C..13..Cr welded joints is discussed. Especially, initiation process is focused. Mainly electrochemical measurement using solution flow type micro-droplet cell and surface analysis of weld joints are conducted. In the evaluation of electrochemical behavior of low C-13%Cr welded joints with and without PWHT (Post Welded Heat Treatment) by the use of a solution flow type micro-droplet cell, PWHT leads to more noble and stable potential in HAZ (Heat Affected Zone) compared to as-welded condition. In the HAZ portion of the as-welded joint, Cr depleted layer was detected under welding scale with the use of GDS (Glow Discharge Spectrometer). PWHT was confirmed to eliminate Cr depleted layer under welding scale. This can be an initiation of SCC near girth welded joint in hot acid environment. Finally, mechanism of SCC initiation near fusion line of as-welded joint was proposed. Localized corrosionwould start at Cr depleted layer under welding oxide scale. This dissolution was also accelerated by a galvanic effect due to a large cathode area of base metal.
  • Alkali leaching of Ni-Al alloy microchannel lining layers
    Y. Saito, T. Ohmi, M. Sakairi, M. Iguchi
    Journal of JSEM, 11, ss276, ss279, 日本実験力学会, 2011年, [査読有り]
    英語, 研究論文(学術雑誌), We investigate alkali leaching of Ni-Al alloy microchannel lining layers to produce a metallic microreactor for high-temperature catalytic reactions. The microchannels and the lining layers were produced by a powder-metallurgical microchanneling process with Ni powder and Al wires. We explored the conditions for the process to produce an Al3Ni or Al3Ni2 lining layer. The Al concentration of the lining layers was successfully decreased by alkali leaching.
  • Electrochemical detection of hydrogen generated by atmospheric corrosion of scratches in zinc coated steels - Effect of the scratched area
    Shogo Takagi, Masatoshi Sakairi
    Zairyo to Kankyo/ Corrosion Engineering, 60, 10, 435, 437, 2011年, [査読有り]
    英語, 研究論文(学術雑誌), A micro-electrochemical cell for detecting permeated hydrogen, which is generated by atmospheric corrosion at small scratched areas on coated steel, was developed. It is possible to measure hydrogen permeation currents in the nano-ampere range. Using this cell, the influence of the scratched area on the hydrogen generated by the corrosion was investigated. The formation of galvanic couples between steel substrate and coating plays an important role in the generation of the hydrogen during atmospheric corrosion, and the amount of permeated hydrogen increases with larger areas of scratches.
  • Anodizing of the inner wall of the microchannel formed in sintered aluminum body
    M. Ishida, T. Ohmi, M. Sakairi, M. Iguchi
    Journal of JSEM, 11, ss267, ss271, 日本実験力学会, 2011年, [査読有り]
    英語, 研究論文(学術雑誌), A fabrication method of a nanoporous anodic alumina film on the inner wall of a microchannel was investigated. An open microchannel was produced by a powder-metallurgical microchanneling process using Al as a body metal and Zn as a sacrificial-core metal. However, the cross-sectional area of the microchannel was larger than that of the sacrificial core; it increased as the compacting pressure increased. The nanoporous alumina film was produced by anodic oxidation of the inner wall of the microchannel.
  • Dealloying of Cu-Zn alloy microchannel lining layers for producing microporous catalyst
    K. Kobayashi, T. Ohmi, M. Sakairi, M. Iguchi
    Journal of JSEM, 11, ss280, ss283, The Japanese Society for Experimental Mechanics, 2011年, [査読有り]
    英語, 研究論文(学術雑誌), A Cu-Zn alloy microchannel lining layer was fabricated by a powder-metallurgical process using Cu powder and Zn wire. The effects of the dealloying treatment on the composition and structure of the lining layer were investigated. The lining layer became more porous and dezinced as the dealloying time increased. In the case of long-time dealloying, Zn-based corrosion products precipitated. These results indicated the possibility of the control of the structure and composition of the inner wall of the microchannel.
  • Area selective formation of porous type aluminum anodic oxide film by a solution flow-type micro droplet cell
    Murata T, Goto Y, Sakairi M, Fushimi K, Kikuchi T
    ECS Transactions, 33, 16, 57, 63, 2011年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Anodic Oxidation of the Inner Wall of the Microchannel Formed in Sintered Aluminum Body               
    Masashi ISHIDA, Tatsuya OHMI, Masatoshi SAKAIRI, Manabu IGUCHI
    Proc. 5th International Symposium on Advanced Science and Technology in Experimental Mechanics, [1/1(CD-ROM)], 068, 2010年11月, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Influence of wettability on corrosion resistance of anodized aluminum in NaCl solution
    M. Zheng, H. Jha, M. Sakairi, T. Kikuchi
    Zairyo-to-Kankyo, 59, 9, 335, 337, 腐食防食協会, 2010年09月, [査読有り]
    英語, 研究論文(学術雑誌)
  • 導電性高分子を用いた再利用可能なアルミニウム製印刷板の試作
    菊地竜也, 島口寛子, 上田幹人, 坂入正敏, 米澤徹, 高橋英明
    表面技術, 61, 9, 652, 657, 表面技術協会, 2010年09月, [査読有り]
    日本語, A printing plate for gravure printing consisting of five layers of aluminum alloy / anodic oxide film / nickel / polypyrrole / copper was fabricated by anodizing, electro-less plating, electroplating, and electro-polymerization. Nickel layers were first deposited on anodic oxide film-covered aluminum alloy by electro-less plating and electroplating. The polypyrrole layer was then deposited on the nickel layer by anodic polarization in a pyrrole monomer solution. Many copper fine particles were deposited on the polypyrrole-deposited specimen at the initial stage of electroplating in the CuSO4 / H2SO4 solution; then a continuous copper layer was obtained through longer cathodic polarization. The copper layer with polypyrrole was removed easily from the nickel layer by pulling with adhesive tape, which suggests that the structure is useful as a reusable aluminum printing plate by copper electroplating and electro-polymerization.
  • Corrosion of Al-Sn-Bi alloys in alcohols at high temperatures. Part II: Effect of anodizing on corrosion
    Tatsuya Kikuchi, Yasuhito Hara, Masatoshi Sakairi, Tetsu Yonezawa, Akira Yamauchi, Hideaki Takahashi
    CORROSION SCIENCE, 52, 8, 2525, 2534, PERGAMON-ELSEVIER SCIENCE LTD, 2010年08月, [査読有り]
    英語, 研究論文(学術雑誌), Nine kinds of Al alloys were anodized to form porous anodic oxide films, and then anodized specimens were immersed in 2-(2-(2-methoxyethoxy)ethoxy)ethanol (MEEE) and 2-(2-(2-butoxyethoxy)ethoxy)ethanol (BEEE) at 415 K. Al-1.0%Sn-1.0%Bi alloy was corroded severely in both BEEE and MEEE, whereas other eight alloys showed no corrosion. The corrosion proceeded under the anodic oxide films through cracks formed in the film. Cathodic polarization in Cu electroplating solution after corrosion suggested that the crack formation during immersion in hot MEEE is due to thermal expansion of the substrate and Sn and Bi containing particles included in the anodic oxide film. (C) 2010 Elsevier Ltd. All rights reserved.
  • Corrosion of Al-Sn-Bi alloys in alcohol at high temperatures. Part I: Effects of the metallurgical structure of the alloys and the metal salt additions to alcohol
    Tatsuya Kikuchi, Yasuhito Hara, Masatoshi Sakairi, Tetsu Yonezawa, Akira Yamauchi, Hideaki Takahashi
    CORROSION SCIENCE, 52, 4, 1482, 1491, PERGAMON-ELSEVIER SCIENCE LTD, 2010年04月, [査読有り]
    英語, 研究論文(学術雑誌), Corrosion of free machining Al alloys that contain Sn and Bi was investigated at 391-415 K in 2-(2-(2-methoxyethoxy)ethoxy)ethanol (MEEE) and 2-(2-(2-butoxyethoxy)ethoxy)ethanol (BEEE) with/without SnCl(2), Sn(OC(2)H(5))(4), FeCl(3), and CuCl(2). The Al-Sn-Bi alloy displayed severe pitting corrosion in MEEE similar to the Al-Sn alloy in BEEE at 415 K, and Sn and Sn/Bi were enriched on the surface of pits. Immersion tests of pure Al in MEEE containing Sn/Cu-salts at 415 K also showed severe corrosion and the deposition of metallic Sn and Cu on the surface. The corrosion mechanisms are discussed in terms of the electro-catalytic activity of the Sn enriched on the surface. (C) 2009 Elsevier Ltd. All rights reserved.
  • Formation of artificial micro-pits on Al alloy with the photon rupture method and the localized corrosion behavior of the formed pits
    K. Yanada, M. Sakairi, T. Kikuchi, Y. Oya, Y. Kojima
    SURFACE AND INTERFACE ANALYSIS, 42, 4, 189, 193, JOHN WILEY & SONS LTD, 2010年04月, [査読有り]
    英語, 研究論文(学術雑誌), An in situ artificial micro-pit fabrication method with an area selective electrochemical measurement technique was applied to investigate the effect of the geometry of artificially formed pits on their localized corrosion behavior in anodized 1000 series aluminum. This technique enables the fabrication of artificial micro-pits with different aspect ratios (pit depth/pit diameter) in solutions. The aspect ratios of the fabricated artificial micro-pits in this experiment could be varied from 0.13 to 1.83 by controlling the irradiation time of the focused pulsed YAG laser beam. By applying a constant potential to the final laser-beam-irradiated spot in chloride environments, localized dissolution occurred only at the laser beam irradiated area, because the anodic oxide film acted as an insulator. The corrosion current and charge increase with increasing aspect ratio at any applied potential. Copyright (C) 2010 John Wiley & Sons, Ltd.
  • The influence of initial surface conditions on field crystallization of anodic aluminum oxide films determined by synchrotron X-ray diffraction
    M. Sakairi, T. Kikuchi, T. Suda, D. Nagasawa, M. Sato
    SURFACE AND INTERFACE ANALYSIS, 42, 4, 215, 220, JOHN WILEY & SONS LTD, 2010年04月, [査読有り]
    英語, 研究論文(学術雑誌), X-ray diffraction measurements were performed using synchrotron radiation at the SPring-8 facility and electrochemical techniques to investigate the effect of polishing methods and storage conditions on the crystal structure of air-formed oxide films and anodic oxide films formed on highly pure aluminum. Storage in an N(2) environment hinders local film breakdown during anodizing, and it was established that the X-ray diffraction measurements showed the presence of a gamma-Al(2)O(3) in the anodic oxide film formed on mechanically polished (MP) specimens. Formation of gamma-Al(2)O(3) during anodizing was inhibited by electropolishing because of the removal of the work-hardened layer that was formed on the MP by electro-polishing. The X-ray diffraction results do not show clear differences in the influence of the polishing method on the crystal structure of air formed oxide film. This is due to the very fast oxidation rate of the air-formed oxide film and very long storage times for the X-ray measurements. The anodic oxide film formed on aluminum, which has a very flat surface, shows color and the color depended on grain orientation. The electrochemical impedance of the MP specimen is slightly lower than that of the mechanically and then electrochemically polished specimen at the middle frequency range. This impedance difference may be due to formation of gamma-Al(2)O(3) in the amorphous anodic oxide film and the thickness of the film. Copyright (C) 2010 John Wiley & Sons, Ltd.
  • Aluminum Microstructures on Anodic Alumina for Aluminum Wiring Boards
    Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    ACS APPLIED MATERIALS & INTERFACES, 2, 3, 774, 777, AMER CHEMICAL SOC, 2010年03月, [査読有り]
    英語, 研究論文(学術雑誌), The paper demonstrates simple methods for the fabrication of aluminum microstructures on the anodic oxide him of aluminum. The aluminum sheets were first engraved (patterned) either by laser beam or by embossing to form deep grooves on the surface. One side of the sheet was then anodized, blocking the other side by using polymer mask to form the anodic alumina. Because of the lower thickness at the bottom part of the grooves, the part was completely anodized before the complete oxidation of the other parts. Such selectively complete anodizing resulted in the patterns of metallic aluminum on anodic alumina. Using the technique, we fabricated microstructures such as line patterns and a simple wiring circuit-board-like structure on the anodic alumina. The aluminum microstructures fabricated by the techniques were embedded in anodic alumina/aluminum sheet, and this technique is promising for applications in electronic packaging and devices.
  • 同軸2重管溶液フロー型液滴セルを用いるCuマイクロロッドの作製(E)
    坂入 正敏, 後藤 良仁, 伏見 公志, 菊地 竜也, 高橋 英明
    電気化学および工業物理化学 : denki kagaku, 78, 2, 118, 121, 電気化学会, 2010年02月, [査読有り]
    英語, 研究論文(学術雑誌), A new method for mask-less fabrication of metal micro-rods is described. The developed solution flow type droplet cell micro fabrication technique was applied to form Cu micro-rods. The use of an inner capillary tube as a mold during electrodeposition, makes it possible to form Cu micro-rods of about 15 mm length and about 100 mu m diameter. The length is controlled by the deposition time. From X-ray analysis and surface observations, the formed Cu micro-rod is polycrystalline and the crystals are very fine. The cross section of the micro-rod was almost circular and the diameter was almost the same throughout its length. This technique also makes it possible to form straight metal structures as well as branched and layered micro-rods. This layered micro-rod fabrication technique can be applied to form resistance controlled micro wires.
  • Model cut-edge formed on zinc coated steels by laser machining and its corrosion behavior               
    M. Sakairi, A. Kageyama, T. Kikuhci
    Corrosion Science and Technology, 9, 1, 29, 33, 2010年01月, [査読有り]
    英語, 研究論文(学術雑誌)
  • 水素急増合金と空気熱交換式容器を用いた住宅・自立電源用抵コスト水素彫像システムに関する研究−第2報水素吸放出特性に与える高平衡厚合金とフィン付・小径容器の効果
    白土博康, 濱田靖弘, 須田孝徳, 坂入正敏, 岡 喜秋, 林 宏樹, 池田英明, 長野克則
    空気調和・衛生工学会論文集, 159, 159, 1, 9, 公益社団法人 空気調和・衛生工学会, 2010年01月, [査読有り]
    日本語, 研究論文(学術雑誌), 本論文は,水素吸蔵合金と空気熱交換式容器を用いた水素貯蔵システムに関する一連の研究の第2報であり,水素吸蔵合金としてMmNi_5を取り上げ,フィン付容器,小径容器を用い,システムの水素吸放出特性の向上と自立電源または住宅における改質器型燃料電池の負荷追従用としての導入可能性について検討した.自立電源としてのフィン付容器,住宅用改質型燃料電池の負荷追従用としての小径容器のいずれも水素吸放出流量・総水素吸蔵量の双方の観点から十分実用性があり,導入可能性は高いと考えられる.
  • Effect of cations on corrosion behavior of aluminum alloy in model tap water
    Kyohei Otani, Masatoshi Sakairi, Tatsuya Kikuchi, Akira Kaneko
    Zairyo to Kankyo/ Corrosion Engineering, 59, 9, 330, 331, Japan Society of Corrosion Engineering, 2010年, [査読有り]
    英語, 研究論文(学術雑誌), The effect of cations on corrosion behavior of A3003-H24 in model tap water with immersion corrosion test and galvanic corrosion test was investigated. A3003-H24 (7 × 7 mm2) sheets were used as specimens. Doubly distilled water, 0.5 kmol m-3 H3BO3/0.05 kmol m-3Na2B4O7 with 1 mol m-3 NaCl, 1 mol m-3 KCl, and 0.5 mol m-3 NaCl/0.5 mol m-3 KCl solutions were used as model tap water. The galvanic current and specimen potential were measured for 86.4 ks at 298 K during galvanic corrosion tests. The results showed that the color of the specimens after immersion corrosion tests changes into light gray, and corrosion pits were also observed. The charge density in mixed cations added solution was lower than those of in single cation added solutions. The results suggested that coexistence of Na+ and K+ in dilute chloride ion solution acts as corrosion inhibitor.
  • Development of a Low Solution Resistance Type Solution Flow Droplet Cell and Investigation of Its Electrochemical Performance
    Masatoshi Sakairi, Takuya Murata, Tatsuya Kikuchi, Koji Fushimi
    ISIJ INTERNATIONAL, 50, 10, 1466, 1470, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2010年, [査読有り]
    英語, 研究論文(学術雑誌), A solution resistance reduced solution flow type micro-droplet cell with co-axial dual capillary tubes was developed. A Pt counter electrode wire, 50 mu m diameter, inserted in the inner capillary tube, successfully reduced solution resistance between the working and counter electrodes. The potentio-dynamic polarization measurements showed the electrochemical performance of developed droplet cell to be very similar to that of traditional macro sized electrochemical cells. The developed droplet cell was applied to obtain line profiles of a current at a constant potential across the surface of for cross-sections of model metal interfaces. The current changed at the model interface between deposited nickel and substrate, and the spatial resolution of the developed droplet cell was reduced with increasing scanning speed of the cell. The results reported in this paper suggest that this technique would be able to measure differences in corrosion resistance in welded metal components and base metals.
  • Fromation of nanoporous anodic oxide films on Ti-Al microchannel walls
    M. Ishida, T. Ohmi, M. Sakairi, M. Iguchi
    Journal of JSEM, 10, 210, 214, The Japanese Society for Experimental Mechanics, 2010年, [査読有り]
    英語, 研究論文(学術雑誌), Fabrication of a nanoporous anodic oxide film on the inner wall of a microchannel was experimented. The microchannel was produced in a titanium body by a powder-metallurgical microchanneling process and was lined with a Ti-Al alloy layer. We found an appropriate anodic condition for an exposed planner surface of the Ti-Al alloy layer. In the case of the microchannel, the growth of the nanoporous oxide film tended to retard deep inside the channel. This problem was easily solved by lengthening the anodic oxidation time.
  • Formation of model scratch on pre-painted coated steel by laser machining and its wet/dry corrosion behavior
    Masatoshi Sakairi, Miki Uchida, Tatsuya Kikuchi
    Zairyo to Kankyo/ Corrosion Engineering, 59, 10, 379, 381, Japan Society of Corrosion Engineering, 2010年, [査読有り]
    英語, 研究論文(学術雑誌), A study was conducted to investigate the formation of model scratch on pre-painted coated steel by laser machining and its wet/dry corrosion behavior. Two different pre-painted coated steel sheets, zinc coated, and zinc-55 mass% aluminum alloy coated were used as specimen. Specimens were irradiated by a focused Nd-YAG laser beam in 0.5 kmol m-3 H3B0 3/0.05 kmol m-3 Na2B4O7 solutions, while laser beam irradiation, specimens were moved by X-Y stage to control 5r = 0.7 to 6.0 to form model scratch. Investigations revealed also that there were white corrosion products at rim and inside of formed model scratch, and the total amount of corrosion products of each specimen did not show any significant difference.
  • The Effect of Surface Condition and Solution Composition on the Repassivation Behavior of Titanium Studied by PRM in Vitro
    M. Sakairi, H. Miyata, M. Kinjyo, T. Kikuchi
    OXIDE FILMS, 25, 40, 37, 45, ELECTROCHEMICAL SOC INC, 2010年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), The effect of the surface condition and solution composition on the localized repassivation kinetics of titanium was investigated by the photon rupture method, PRM, and electrochemical techniques in aqueous electrolytes. The log I vs. log t plots after laser beam irradiation showed a rapid increase, then a decrease with a slope steeper than -1.0, which is steeper than that expected from high field oxide film formation theory, suggesting that the repassivation of titanium is a combination of electrochemical and chemical reactions. The repassivation current increases with increases in the applied potential and is suppressed with hydroxylapatite (HAp) coating, while solution compositions do not influence the repassivation kinetics. The effect of a HAp coating on the repassivation kinetics can be explained by local pH changes caused by dissolution of the HAp.
  • Wet/Dry Cycle Corrosion Behavior of Model Cut-Edge Formed on Pre-painted Zinc Alloy Coated Steels by Laser Fabrication
    M. Sakairi, A. Kageyama, T. Kikuchi
    COATINGS FOR CORROSION PROTECTION, 25, 29, 71, 79, ELECTROCHEMICAL SOC INC, 2010年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), Laser machining technique, which used focusing pulse YAG laser beam irradiation, was applied to form area ratio of controlled model cut-edge on pre-painted zinc related coated steels. A corrosion behavior of formed model cut-edge was investigated by wet/dry cyclic corrosion test using 10 mol m(-3) NaCl solutions in 80 % R. H. atmosphere. In high area ratio zinc specimens, red rust is observed on steel substrate at model cut-edge. The chromate inhibits corrosion of formed model cut-edge on pre-painted zinc coated steels. The behavior of corrosion penetration under the paint depends on composition of coating. In the case of painted zinc-55 mass% aluminum coated steel, zinc rich phase preferentially dissolved. The preferential zinc rich layer dissolution and corrosion products formation cause paint peel off.
  • Growth of porous type anodic oxide films at micro-areas on aluminum exposed by laser irradiation
    Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    ELECTROCHIMICA ACTA, 54, 27, 7018, 7024, PERGAMON-ELSEVIER SCIENCE LTD, 2009年11月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum covered with pore-sealed anodic oxide films was irradiated with a pulsed Nd-YAG laser to remove the oxide film at micro-areas. The specimen was re-anodized for long periods to examine the growth of porous anodic oxide films at the area where substrate had been exposed by measuring current variations and morphological changes in the oxide during the re-anodizing. The chemical dissolution resistance of the pore-sealed anodic oxide films in an oxalic acid solution was also examined by measuring time-variations in rest potentials during immersion.
    The resistance to chemical dissolution of the oxide film became higher with increasing pore-sealing time and showed higher values at lower solution temperatures. During potentiostatic re-anodizing at five 35-mu m wide and 4-mm long lines for 72 h after the film was removed the measured current was found to increase linearly with time. Semicircular columnar-shaped porous type anodic oxide was found to form during the re-anodizing at the laser-irradiated area, and was found to grow radially, thus resulting in an increase in the diameter. After long re-anodizing, the central and top parts of the oxide protruded along the longitudinal direction of the laser-irradiated area. The volume expansion during re-anodizing resulted in the formation of cracks, parallel to the lines, in the oxide film formed during the first anodizing. (C) 2009 Elsevier Ltd. All rights reserved.
  • Anodic Oxidation of the Inner Wall of the Microchannel Formed by Ti-Al Reactive Infiltration               
    Masashi Ishida, Tatsuya Ohmi, Masatoshi Sakairi, Manabu Iguchi
    Proc. 4th International Symposium on Advanced Fluid/Solid Science and Technology in Experimental Mechanics (ISEM2009), [1/1(CD-ROM)], MA-V-3, 2009年11月, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Palladium nanoparticle seeded electroless metallization of Al/Al2O3 surfaces
    Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    MATERIALS LETTERS, 63, 16, 1451, 1454, ELSEVIER SCIENCE BV, 2009年06月, [査読有り]
    英語, 研究論文(学術雑誌), A simple method for the formation of palladium nanoparticles on aluminum and aluminum oxide surface is demonstrated. In the present method. the palladium nanoparticles obtained directly on the solid surface by immersing the specimen in palladium(II)acetate solution followed by reduction to metallic palladium by using sodium hypophosphite. In the investigation, as-received, boiled, electropolished and anodized aluminum was used as substrate. Additionally, the method is combined with the electroless nickel plating, which facilitates two steps metallization technique on the respective surfaces. In these cases, specimens were first immersed in palladium(II)acetate solution followed by immersion in electroless nickel plating solution, where, palladium reduced on the specimen surface providing catalytic site for the subsequent electroless nickel deposition. Using the technique. about 6 to 8.5 mu m thick Ni-P metallic layer was deposited on the specimen surface. (c) 2009 Elsevier B.V. All rights reserved.
  • ポリピロール/金の2層構造を有する3次元マイクロアクチュエーターの作製
    菊地竜也, 上田晋吾, 上田幹人, 坂入正敏, 高橋英明
    表面技術, 60, 5, 335, 341, 2009年05月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • ポリピロール/金の2層構造を有する3次元マイクロアクチュエーターの作製
    菊地 竜也, 上田 晋吾, 上田 幹人, 坂入 正敏, 高橋 英明
    表面技術 = The journal of the Surface Finishing Society of Japan, 60, 5, 335, 341, 表面技術協会, 2009年05月, [査読有り]
    日本語, Three-dimensional micro-actuators, consisting of a polypyrrole (PPy)/Au bi-layer, were fabricated by Al anodizing, laser irradiation, and electrochemical techniques. Aluminum specimens covered with porous type oxide films were irradiated with a pulsed Nd-YAG laser to locally remove the oxide films, and then an Au layer and a PPy layer were deposited at the area where the film had been removed. Finally, the specimens were immersed in a NaOH solution after connecting with/without a Pt plate to separate PPy/Au actuators from the Al substrate and anodic oxide film. The PPy layer didn’t lose its...
  • Metallization of oxide / hydroxide film of aluminum: the palladium activation techniques
    H. Jha, T. Kikuchi, M. Sakairi, H. Takahashi
    表面技術, 60, 3, 208, 212, 2009年03月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Optimization of environment-friendly electrochemical polishing process for titanium plate electrode               
    Masatoshi Sakairi, Misaki Kinjyo, Tatsuya Kikuchi
    The Minerals, Metals and Materials Society - 3rd International Conference on Processing Materials for Properties 2008, PMP III, 1, 71, 75, 2009年
    英語, 研究論文(国際会議プロシーディングス), A newly developed environment-friendly NaCl ethylene glycol type electrochemical polishing solution was used to the polishing titanium plate, used for localized corrosion tests in model body fluids. The NaCl concentration, agitation speed, applied cell voltage and duration was changed to investigate optimum conditions. The anodizing curves were measured to elucidate polishing conditions. The optimum polished surfaces was obtained by applying a voltage of initial 25 V for 180 s then 10 V for 600 s at room temperature in 1.27 kmol/m3 NaCl ethylene glycol solution. Only 0.15 dm3 solution is needed to polish more than ten sheets (10 mm x 10 mm) of titanium with this condition.
  • Growth of multioxide planar film with the nanoscale inner structure via anodizing Al/Ta layers on Si
    A. Mozalev, A. J. Smith, S. Borodin, A. Plihauka, A. W. Hassel, M. Sakairi, H. Takahashi
    ELECTROCHIMICA ACTA, 54, 3, 935, 945, PERGAMON-ELSEVIER SCIENCE LTD, 2009年01月, [査読有り]
    英語, 研究論文(学術雑誌), An Al/Ta bilayer specimen prepared by a successive sputter-deposition of a 150-nm tantalum layer and a 180-nm aluminium layer onto a silicon wafer is anodically processed in a sequence of steps in oxalic acid electrolytes, at voltages of up to 53V, which generates a 260-nm alumina film with well-ordered nanoporous structure. Further potentiodynamic reanodizing the specimen to 220 V causes the simultaneous growth of a 65-nm tantalum oxide layer beneath the alumina film and an array of oxide 'nanocolumns' (similar to 50 mn wide, similar to 80 nm apart, similar to 7 x 10(9) cm(-2) population density) penetrating the alumina pores and reaching precisely to the top of the alumina film. The complete filling of the alumina pores is assisted by the high Pilling-Bedworth ratio for Ta/Ta2O5 and a substantially increased transport number for tantalum species (0.4), which is an average value of all migrating tantalum ions with different oxidation states. The nanocolumns are shown to be composed of a unique, regular mixture of Ta2O5 (dominating amount), suboxides TaO2 and TaOx (0.5 < x < 1), Al2O3, metallic Ta and Al aggregates, tantalum diboride (TaB2) and oxidized boron from the electrolyte. The ionic transport processes determining the self-organized growth of these planar oxide nanostructures are considered and described conceptually. (c) 2008 Elsevier Ltd. All rights reserved.
  • Effect of potential, temperature, and fluoride ions on the repassivation kinetics of titanium in phosphate buffered saline solution with the photon rupture method
    Masatoshi Sakairi, Hiroomi Miyata, Tatsuya Kikuchi, Hideaki Takahashi
    Laser Chemistry, 2009, 436065, 2009年, [査読有り]
    英語, 研究論文(学術雑誌), The effect of the applied potentials, temperature, and F - ions on the localized repassivation kinetics of titanium was investigated by the photon rupture method, PRM, and electrochemical techniques in phosphate buffered saline solution. The log I versus log t plots after laser beam irradiation showed a rapid increase, then a decrease with a slope of about -1.5, which is steeper than that expected from high field oxide film formation theory, suggesting that the repassivation of titanium is a combination of electrochemical and chemical reactions. The repassivation current increases with increases in the applied potential and addition of F - ions, while solution temperature does not influence the repassivation kinetics. The effect of F - ions on the repassivation kinetics can be explained by localized pH changes caused by very rapid dissolution of titanium when titanium was exposed to PBS solution. Copyright © 2009 Masatoshi Sakairi et al.
  • Effect of aspect ratio of artificial pits formed on anodized Al by PRM on localized corrosion in chloride environments
    M. Sakairi, A. Kageyama, Y. Kojima, Y. Oya, T. Kikuchi
    ECS Transactions, 16, 43, 19, 28, 2009年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), New in solution type artificial pit formation with area selective electrochemical measurement technique was established. Artificial pits were formed on anodized 1070 aluminum in solutions by continuous focused pulse YAG laser beam irradiation. The aspect ratio (pit depth/pit width) of formed pit can be changed from 0.45 to 1.23 by controlling laser beam irradiation time. As applying constant potential while laser irradiation in chloride environments, localized dissolution was occurred only at the laser beam irradiated area, because of the anodic oxide film act as insulator. The corrosion current increases with increasing aspect ratio at the same applied potential, however, aspect ratio of the pit does not show an influence on repassivation behavior of 1070 aluminum alloy. ©The Electrochemical Society.
  • Highly uniform aluminum oxy-hydroxide nanofiber from porous anodic alumina
    Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    ECS Transactions, 16, 25, 91, 96, 2009年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), A simple and effective method for the synthesis of aluminum oxyhydroxide nanofiber is demonstrated. In this method, porous anodic oxide film of aluminum (porous anodic alumina) is used to synthesize the nanofibers, where it acts both as a precursor as well as the template. Initially, the porous oxide film is hydrothermally treated for the formation of hydroxide (boehmite or pseudoboehmite) inside the oxide pores, and then the porous oxide is selectively etched from the film, using tri-sodium citrate solution, leaving the hydroxide intact. The method results in highly uniform aluminum oxy-hydroxide nanofibers. The size (diameter) of the nanofiber was controlled by controlling the size of the pores in the anodic oxide film. ©The Electrochemical Society.
  • Electrochemical Noise Analysis of 13 mass% Cr Stainless Steel HAZ by Solution Flow Type Micro-droplet Cell-Effect of Solution Concentration-
    S. Hashizume, T. Nakayama, M. Sakairi, K. Fushimi
    ECS transactions, 16, 52, 281, 290, 2009年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Development of a novel microstructure fabrication method with co-axial dual capillary solution flow type droplet cells and electrochemical deposition
    Sakairi Masatoshi, Sato Fumihito, Gotou Yoshihito, Fushimi Koji, Kikuchi Tatsuya, Takahashi Hideak
    Electrochimica Acta, 54, 2, 616, 622, 2008年12月30日, [査読有り]
    英語, 研究論文(学術雑誌)
  • Fabrication of micro-dot arrays and micro-walls of acrylic acid/melamine resin on aluminum by AFM probe processing and electrophoretic coating
    S. Kurokawa, T. Kikuchi, M. Sakairi, H. Takahashi
    ELECTROCHIMICA ACTA, 53, 28, 8118, 8127, PERGAMON-ELSEVIER SCIENCE LTD, 2008年11月, [査読有り]
    英語, 研究論文(学術雑誌), Micro-dot arrays and micro-walls of acrylic acid/melamine resin were fabricated on aluminum by anodizing, atomic force microscope (AFM) probe processing, and electrophoretic deposition. Barrier type anodic oxide films of 15 rim thickness were formed on aluminum and then the specimen was scratched with an AFM probe in a solution containing acrylic acid/melamine resin nano-particles to remove the anodic oxide film locally. After scratching, the specimen was anodically polarized to deposit acrylic acid/melamine resin electrophoretically at the film-removed area. The resin deposited on the specimen was finally cured by heating.
    It was found that scratching with the AFM probe on open circuit leads to the contamination of the probe with resin, due to positive shifts in the potential during scratching. Scratching of the specimen under potentiostatic conditions at -1.0 V, however, resulted in successful resin deposition at the film-removed area without probe contamination. The rate of resin deposition increased as the specimen potential becomes more positive during electrophoretic deposition. Arrays of resin dots with a few to several tens mu m diameter and 100-1000 nm height, and resin walls with 100-1000 nm height and 1 mu m width were obtained on specimens by successive anodizing, probe processing. and electrophoretic deposition. (C) 2008 Elsevier Ltd. All rights reserved.
  • Synthesis of aluminum oxy-hydroxide nanofibers from porous anodic alumina
    Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    NANOTECHNOLOGY, 19, 39, 395603, IOP PUBLISHING LTD, 2008年10月, [査読有り]
    英語, 研究論文(学術雑誌), A novel method for the synthesis of aluminum oxy-hydroxide nanofibers from a porous anodic oxide film of aluminum is demonstrated. In the present method, the porous anodic alumina not only acts as a template, but also serves as the starting material for the synthesis. The porous anodic alumina film is hydrothermally treated for pore-sealing, which forms aluminum oxy-hydroxide inside the pores of the oxide film as well as on the surface of the film. The hydrothermally sealed porous oxide film is immersed in the sodium citrate solution, which selectively etches the porous aluminum oxide from the film, leaving the oxy-hydroxide intact. The method is simple and gives highly uniform aluminum oxy-hydroxide nanofibers. Moreover, the diameter of the nanofibers can be controlled by controlling the pore size of the porous anodic alumina film, which depends on the anodizing conditions. Nanofibers with diameters of about 38-85 nm, having uniform shape and size, were successfully synthesized using the present method.
  • 無電解めっきとレーザー照射による有機樹脂板上へのCuマイクロパターン形成
    菊地 竜也, 和智 悠太, 坂入 正敏, 高橋 英明, 飯野 潔, 片山 直樹
    表面技術 = The journal of the Surface Finishing Society of Japan, 59, 8, 555, 561, 表面技術協会, 2008年08月, [査読有り]
    日本語, Printed circuit board with a Cu fine pattern was fabricated by electroless plating and laser irradiation. A glass fiber-reinforced epoxy resin plate was immersed in a Pd2+ containing solution, and then Cu metal layer was deposited on the epoxy resin by Cu electroless plating. After Cu plating, the Cu deposited specimen was irradiated with a pulsed Nd-YAG laser in air or doubly distilled water through an iris diaphragm and a convex lens to remove the Cu layer locally. The width of the Cu removed area in creased with increasing laser power and with decreasing scanning rate of the laser beam. ...
  • 水素急増合金と空気熱交換式容器を用いた住宅・自立電源用抵コスト水素彫像システムに関する研究ー第1報空気熱交換式容器を用いた水素吸蔵システムの水素吸放出挙動
    白土博康, 濱田靖弘, 須田孝徳, 坂入正敏, 岡 喜秋, 林 宏樹, 池田英明, 長野克則
    空気調和・衛生工学会論文集, 134, 134, 11, 19, 公益社団法人 空気調和・衛生工学会, 2008年05月, [査読有り]
    日本語, 研究論文(学術雑誌), 本論文において,住宅エネルギーシステムまたは自立電源システム用を想定して,水素吸蔵合金と空気熱交換式容器による水素貯蔵システムの水素吸放出挙動について明らかにした.本水素貯蔵システムにおける水素放出特性は,合金の平衡解離圧と配管圧の差が0.1MPa以上の時,良好であった.また,吸蔵圧力を0.8MPaとした時,本システムの有効水素吸蔵量は室温や吸蔵流量に依存し,室温5,20℃,設定流量0.1NL/(min・kg),または室温35℃,設定流量0.025,0.05NL/(min・kg)において,高い水素吸蔵量が確保し得ることを示した.
  • カソード分極中におけるアノード酸化皮膜化成ニオブ電極への水素吸収
    長原 和宏, 菊地 竜也, 伏見 公志, 坂入 正敏, 高橋 英明, 泉 知夫
    表面技術 = The Journal of the Surface Finishing Society of Japan, 59, 5, 326, 332, 一般社団法人 表面技術協会, 2008年05月, [査読有り]
    日本語, Cathodic polarization of niobium specimens that have been anodized galvanostatically up to Ea=100V, and then potentiostatically at Ea=100V has been investigated in a neutral borate solution. During potetiostatic cathodic polarization below Ec=−2.36V (vs. RHE) in both aerated and deaerated solutions, the cathodic current increased rapidly initially, and then increased gradually until it reached a steady value. Hydrogen gas evolution was observed during cathodic polarization below Ec=−2.36V with no formation of blisters and pits, suggesting that H+ reduction occurs mainly at the film surface....
  • 陽極酸化したアルミニウムの異種金属接触腐食 : 酸化物皮膜構造と塩化物イオン濃度の影響
    坂入 正敏, 下山 由起也, 長澤 大介, 菊地 竜也, 高橋 英明
    材料と環境 : zairyo-to-kankyo, 57, 4, 194, 200, 腐食防食協会, 2008年04月, [査読有り]
    日本語, 研究論文(学術雑誌), The effect of anodic oxide film structure, barrier type and porous type on galvanic corrosion resistance of aluminum in 0.5 kmol/m3 H 3BO3/ 0.05 kmol/m3Na2B 4O7 with NaCl was examined by electrochemical random signal (electrochemical noise) analysis technique. When pitting corrosion occurs, rest potential suddenly decreases and current increases rapidly, and rest potential and current change with fluctuation during galvanic corrosion. The galvanic current change correlates closely with corrosion potential change. As the thickness of both types of anodic oxide films and decreasing of chloride ion concentration, the incubation time of pitting corrosion became longer, and incubation time of pitting corrosion of specimen formed porous type anodic oxide film is longer than that of specimen formed barrier type anodic oxide film. The inverse of incubation time increase with chloride ion concentration to the power of n [Cl-]n. The value of n is between 1.2 and 2.5 in both oxide films.
  • Electrochemical random signal analysis during localized corrosion of anodized 1100 aluminum alloy in chloride environments               
    M. Sakairi, Y. Shimoyama, D. Nagasawa
    Corrosion Science and Technology, 7, 3, 168, 172, 2008年03月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Influence of zinc ions on initial stage of localized corrosion of Zn and Zn-Al alloy coated steels with photon rupture method
    Masatoshi Sakairi, Yoshiyuki Uchida, Tatsuya Kikuchi, Hideaki Takahashi
    ISIJ INTERNATIONAL, 48, 7, 988, 993, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2008年, [査読有り]
    英語, 研究論文(学術雑誌), The effect of pre-dissolved Zn ions in the solutions on the initial stage of localized corrosion after oxide films of Zn and Zn-Al alloy coated steels were removed by a photon rupture method, focused pulsed Nd-YAG laser beam irradiation, was investigated electrochemically. Zn ions can be inhibited dissolution of the Zn coated layer by precipitation of zinc hydroxide, which is formed by hydrolysis reaction of dissolved Zn ions in neutral buffer solutions. However, Zn ions do not affect the dissolution of a Zn-Al alloy coated layer. The absence of inhibition of the Zn-Al layer dissolution can be explained by pH change to lower values at the irradiated area by the hydrolysis reaction of the dissolved Al ions. The effect of Zn ions on corrosion inhibition of the coated layer by the photon rupture method established here was in good agreement with polarization experiments.
  • 無電解めっきと電気めっきによるセラミックス上への白金厚膜析出
    菊地 竜也, 渡辺 健, 坂入 正敏, 高橋 英明, 丸子 智弘
    表面技術 = The Journal of the Surface Finishing Society of Japan, 59, 1, 51, 56, 表面技術協会, 2008年01月, [査読有り]
    日本語, Thick platinum metal layer was deposited on ceramics using electroless- and electro-plating. The ceramics, which consist of ZrO2, Al2O3, SiO2, Na2O, and other oxides, were etched in HF solution, and then immersed in a platinum electroless plating solution containing Pt(NH3)2(NO2)2 and N2H4 as a reducting regent. The mass of the ceramics specimen slightly decreased with the electroless plating time and then in creased at a rate depending on temperature, but independent of Pt2+ concentration. Two μm thick platinum layer could be deposited uniformly on ceramics by electroless plating for 14.4k...
  • Electrochemical behavior of low C - 13%Cr weld joints by using solution flow type micro-droplet cell
    Hashizume S, Nakayama T, Sakairi M, Fushimi K
    NACE - International Corrosion Conference Series, 081021, 0810216, 2008年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Microfabrication of an anodic oxide film by anodizing laser-textured aluminium
    Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    JOURNAL OF MICROMECHANICS AND MICROENGINEERING, 17, 10, 1949, 1955, IOP PUBLISHING LTD, 2007年10月, [査読有り]
    英語, 研究論文(学術雑誌), A simple method for the fabrication of microstructures of an aluminium anodic oxide film ( anodic alumina) by anodizing laser-textured aluminium is demonstrated. In the process, the aluminium substrate was first textured by a low power laser beam, and then the textured aluminium was subjected to anodizing, to develop a continuous, thick porous layer on the textured surface. Microstructures with a depth of a few to several tens of micrometres were fabricated successfully on the anodic oxide film by using various combinations of laser power density and laser scanning speed. Removing the film from the aluminium substrate enables the fabrication of various 2D and 3D microstructures from anodic alumina.
  • Dielectric properties of Al-Si composite oxide films formed on electropolished and DC-etched aluminum by electrophoretic sol-gel coating and anodizing
    M. Sunada, H. Takahashi, T. Kikuchi, M. Sakairi, S. Hirai
    JOURNAL OF SOLID STATE ELECTROCHEMISTRY, 11, 10, 1375, 1384, SPRINGER, 2007年10月, [査読有り]
    英語, 研究論文(学術雑誌), Highly pure aluminum specimens (99.99%) after electropolishing and DC-etching were covered with SiO2 films by electrophoretic sol-gel coating and were anodized in neutral boric acid/borate solutions. Time-variations in cell voltage during electrophoretic sol-gel coating and in anode potential during anodizing were monitored. Structure and dielectric properties of the anodic oxide films were examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and electrochemical impedance spectroscopy (EIS). It was found that electrophoretic sol-gel coating forms uniform SiO2 films on the surface of both electropolished and DC-etched specimens. Anodizing of specimens after electrophoretic coating lead to the formation of anodic oxide films consisting of two layers: an inner alumina layer and an outer Al-Si composite oxide layer. The anodic oxide films formed, thus, had slightly higher capacitances than those formed on aluminum without any coating. Higher heating temperatures after electrophoretic deposition caused the increase in capacitance of anodic oxide films more effectively. Anodizing in a boric acid solution after SiO2 coating on DC-etched foil allowed the anode potential to reach a value higher than 1,000 V, resulting in 39% higher capacitances than those on specimens without SiO2 film.
  • Laser micromachining of porous anodic alumina film
    H. Jha, T. Kikuchi, M. Sakairi, H. Takahashi
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 88, 4, 617, 622, SPRINGER, 2007年09月, [査読有り]
    英語, 研究論文(学術雑誌), A laser direct-write process on porous anodic alumina film is carried out for the fabrication of microstructure on the film, using nanosecond, second harmonic Nd:YAG laser. Laser micromachining can be preformed in two different ways on colored and pore-sealed anodic alumina film, to generate microstructures on the film. Removal of the aluminum substrate before laser irradiation greatly improves the shape characteristics of the microstructure. The depth of microstructures can be controlled by the power and the scanning speed of the laser beam. Several structures with depths from 1 to 35 mu m were fabricated on anodic alumina film with good precision and reproducibility.
  • 塩化ニオブを前駆体としたゾルからのNb_2O_5析出とNb_2O_5被覆Alのアノード酸化挙動
    小山 瞬, 菊地 竜也, 坂入 正敏, 高橋 英明, 永田 晋二
    電気化学および工業物理化学 : denki kagaku, 75, 8, 573, 575, 電気化学会, 2007年08月, [査読有り]
    英語, 研究論文(学術雑誌), Formation of Nb2O5 films on aluminum was attempted by sol-gel coating, using NbCl5 as a precursor. The structure and the dielectric properties of anodic oxide films formed on aluminum by sol-gel coating and the subsequent anodizing were examined. Anodic oxide film formed by this process was composed of an inner Al2O3 layer and an outer Nb2O5 layer. The capacitance of the anodic oxide films formed on Nb2O5-coated specimens was at most 34 % higher than that of anodic oxide films on aluminum without coating.
  • Area-selective microscale metallization on porous anodic oxide film of aluminium
    Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, Hideaki Takahashi
    ELECTROCHEMISTRY COMMUNICATIONS, 9, 7, 1596, 1601, ELSEVIER SCIENCE INC, 2007年07月, [査読有り]
    英語, 研究論文(学術雑誌), A new method for micropatterning of metallic patterns on porous anodic oxide film of aluminium is described. The porous anodic oxide film was impregnated with organic dye and palladium ions before the hydrothermal pore-sealing. The surface layers formed during the pore-sealing, i.e. outer acicular hydroxide layer and a compact intermediate sub-layer trap the palladium ion underneath the layers. Exposing the palladium enriched area by the help of laser beam followed by electroless nickel deposition results the deposition of nickel on the laser-exposed part. Thickness of the deposits can be up to about 2-3 mu m, after about the 20 min of immersion in electroless nickel plating bath. The metallic micropatterns, formed by the method are crack free, smooth and uniform over extended length. (C) 2007 Elsevier B.V. All rights reserved.
  • Development of three-electrode type micro-electrochemical reactor on anodized aluminum with photon rupture and electrochemistry
    Masatoshi Sakairi, Masashi Yamada, Tastuya Kikuchi, Hideaki Takahashi
    ELECTROCHIMICA ACTA, 52, 21, 6268, 6274, PERGAMON-ELSEVIER SCIENCE LTD, 2007年06月, [査読有り]
    英語, 研究論文(学術雑誌), Photon rupture with a focused single pulse of pulsed YAG-laser irradiation was used to fabricate an aluminum electrochemical micro-reactor. Porous type anodic oxide film formed on aluminum specimens was irradiated in solutions with a pulsed Nd-YAG laser beam through a convex lens to fabricate micro-channels, micro-electrode, and through holes (for reference electrode, solution inlet, and outlet). During irradiation, specimens were moved by a computer controlled XYZ stage. After irradiation, the surface of the micro-channel and through hole were again treated to form anodic oxide film and the surface of the micro-electrode was treated electrochemically to provide an An layer. The calculated volume of the micro-reactor including micro-channel and through holes is about 1.5 mu l. The cyclic voltammogram of the micro-electrochemical cell was measured in K3Fe(CN)(6)/K4Fe(CN)(6) with both static and flowing solution at different scanning rates. The anodic and cathodic peak currents were measured and the values depended on scanning rate and ion concentration when the solution was static. With the flowing solution, limiting currents were observed and the anodic limiting current was increased with the cubic root of the solution flow rate. (c) 2007 Elsevier Ltd. All rights reserved.
  • Initial stage of localized corrosion in artificial pits formed with photon rupture on Zn-5 mass% Al alloy-coated steel
    Masatoshi Sakairi, Yoshiyuki Uchida, Hideaki Takahashi
    CORROSION SCIENCE, 49, 5, 2362, 2370, PERGAMON-ELSEVIER SCIENCE LTD, 2007年05月, [査読有り]
    英語, 研究論文(学術雑誌), The photon rupture method, by which oxide film and metal are removed by focused pulsed Nd-YAG laser beam irradiation, was applied to form artificial micro-pits in Zn-5 mass% Al alloy-coated steel. The zinc alloy-coated layer was removed by pulsed laser irradiation treatment for about one second in a neutral buffer solution with NaCl. The rest potential transient with the laser treatment was measured. In the early stage of the laser treatment the rest potential of zinc alloy-coated steel changed to the negative direction immediately after every irradiation of a laser pulse and then returned to the previous value. However, after the steel substrate was exposed to the solution, the rest potential moved to the positive direction immediately after every irradiation of a laser pulse and then returned to the previous value. The amplitude and duration of the potential change after the laser irradiation increased with repetition of laser irradiation, related to the pit depth and the exposed area ratio of coated layer/steel substrate. The rest potential fluctuation difference can be explained by galvanic reaction change in the artificial pit formed by laser irradiation on the Zn alloy-coated steel. (C) 2006 Elsevier Ltd. All rights reserved.
  • Micro-patterning in anodic oxide film on aluminium by laser irradiation
    H. Jha, T. Kikuchi, M. Sakairi, H. Takahashi
    ELECTROCHIMICA ACTA, 52, 14, 4724, 4733, PERGAMON-ELSEVIER SCIENCE LTD, 2007年04月, [査読有り]
    英語, 研究論文(学術雑誌), Microstructures such as microchannels and microchambers were fabricated on anodic oxide film of aluminium with laser direct patterning technique. The aluminium substrate covered with porous type anodic oxide film was dyed with organic dyes followed by hydrothermal treatment. The coloured and pore sealed film shows much higher absorption then as-formed porous film, that makes possible to pattern various types of microstructures on the film by removing the upper part of the film surface by laser irradiation. Structure of the crystallized hydroxide layer on the surface of the anodic oxide film, formed during pore sealing, as well as the partial removal of anodic oxide film from the surface is described. Microstructures with depth lower than 1-27 mu m were patterned successfully on 16 and 32 mu m thick anodic oxide film surfaces, using various combinations of laser power and laser scanning speed. The affect of the laser scanning speed and laser power density on the shape of the microstructures is also explained. (c) 2007 Elsevier Ltd. All rights reserved.
  • Fabrication of a three-dimensional micro-manipulator by laser irradiation and electrochemical techniques and the effect of electrolytes on its performance
    T. Kikuchi, Y. Akiyama, A. Ueda, A. Sakairi, H. Takahashi
    ELECTROCHIMICA ACTA, 52, 13, 4480, 4486, PERGAMON-ELSEVIER SCIENCE LTD, 2007年03月, [査読有り]
    英語, 研究論文(学術雑誌), Ribbon type and three-dimensional micro-actuators, consisting of three-layer structure of acrylic acid resin/Au/polypyrrole, were fabricated by aluminum anodizing, laser irradiation, and electrochemical techniques, and their performance was examined. Anodized aluminum specimens were irradiated with a pulsed Nd-YAG laser to remove anodic oxide films locally, and then an An layer was deposited at the area where film had been removed. The subsequent electrophoretic deposition of acrylic acid resin on the An layer, dissolution of anodic oxide film and the metal substrate, and deposition of polypyrrole on backside of An layer by electro-polymerization enabled the fabrication of a three-layer actuator. Cyclic voltammetry of the ribbon type actuator in different electrolyte solutions showed that redox reactions of polypyrrole is accompanied with doping and dedoping of hydrated cations, and that the redox reaction strongly depends on the valency of cations in the solutions. The three-dimensional micro-actuator showed good performance as a manipulator, gripping and moving objects of several milligram in solutions. (c) 2007 Elsevier Ltd. All rights reserved.
  • Mechanism of formation and growth of sunflower-shaped imperfections in anodic oxide films on niobium
    K. Nagahara, M. Sakairi, H. Takahashi, K. Matsumoto, K. Takayama, Y. Oda
    ELECTROCHIMICA ACTA, 52, 5, 2134, 2145, PERGAMON-ELSEVIER SCIENCE LTD, 2007年01月, [査読有り]
    英語, 研究論文(学術雑誌), Anodizing of mobium has been investigated to develop mobium solid electrolytic capacitors. Chemically polished niobium specimens were anodized in a diluted phosphoric acid solution, initially galvanostatically at i(a) = 4 Am-2 up to E-a = 100 V, and then potentiostatically at E-a = 100 V for t(pa) = 43.2 ks. During the galvanostatic anodizing, the anode potential increased almost linearly with time, while, during potentiostatic anodizing, the anodic current decreased up to t(pa) = 3.6 ks, and then increased slowly before decreasing again after t(pa) = 30.0 ks. Images of FE-SEM and in situ AFM showed that nuclei of imperfections were formed at the ridge of cell structures before t(pa) = 3.6 ks. After formation, the imperfection nuclei grew, showing cracking and rolling-up of the anodic oxide film, and crystalline oxide was formed at the center of imperfections after t(pa) = 3.6 ks. The growth of imperfections caused increases in the anodic current between tpa = 3.6 and 30.0 ks. Long-term anodizing caused a coalescence of the imperfections, leading to decreases in the anodic current after t(pa) = 30.0 ks. As the imperfections grew, the dielectric dispersion of the anodic oxide films became serious, showing a bias voltage dependence of the parallel equivalent capacitance, C-p, and a dielectric dissipation factor, tan delta. The mechanism of formation and growth of the imperfections, and the correlation between the structure and dielectric properties of anodic oxide films is discussed. (c) 2006 Elsevier Ltd. All rights reserved.
  • Electrochemical random signal analysis during galvanic corrosion of anodized aluminum alloy
    M. Sakairi, Y. Shimoyama
    Journal of JSEM, 7, 114, 119, 日本実験力学会, 2007年, [査読有り]
    英語, 研究論文(学術雑誌)
  • Investigations on the local electrochemical behavior of welded stainless steels with solution flow type micro-droplet cell               
    T. Nakayama, M. Sakairi, K. Fushimi, S. Hashizume
    Proceedings of EUROCORR 2007 (CD-ROM), 1130, 2007年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス)
  • Local deposition of polypyrrole on aluminum by anodizing, laser irradiation, and electrolytic polymerization and its application to the fabrication of micro-actuators
    Y Akiyama, T Kikuchi, M Ueda, M Iida, M Sakairi, H Takahashi
    ELECTROCHIMICA ACTA, 51, 23, 4834, 4840, PERGAMON-ELSEVIER SCIENCE LTD, 2006年06月, [査読有り]
    英語, 研究論文(学術雑誌), Polypyrrole was deposited at selected areas on aluminum by anodizing, laser irradiation, and electrolytic polymerization, and the application of the technique for fabricating micro-actuators was attempted. Aluminum specimens covered with porous type anodic oxide films were irradiated with a pulsed Nd-YAG laser to remove the oxide films locally, and then thin Ni layers were deposited at areas where film had been removed. Polypyrrole could be successfully deposited only on the Ni layer by anodic polarization of the specimens in pyrrole monomer solution, and a polypyrrole/Ni bilayer structure could be obtained by dissolution of the aluminum substrate and anodic oxide film in NaOH solutions. The bilayer structure was found to be inactive to doping and dedoping of ions during anodic and cathodic polarization. A three-layer structure, nitrocellulose/Ni/polypyrrole, fabricated by electrolytic polymerization after nitrocellulose coating on a Ni layer detached from the aluminum substrate, showed ion-doping and -dedoping activity, suggesting the possibility of fabricating micro-actuators in this manner. (c) 2006 Elsevier Ltd. All rights reserved.
  • 陽極酸化したアルミニウムのガルバニック腐食の電気化学ノイズ解析
    坂入 正敏, 下山 由起也, 高橋 英明
    電気化学および工業物理化学 : denki kagaku, 74, 6, 458, 462, ELECTROCHEMICAL SOC JAPAN, 2006年06月, [査読有り]
    英語, 研究論文(学術雑誌), A new type of electrochemical noise analysis technique with First Fourier Transformation, FFT, was applied to galvanic corrosion of barrier and porous type anodic oxide films formed on aluminum in 0.5 kmol/m(3) H3BO4 / 0.05 kmol/m(3) Na2B4O7 solutions with 0.01 kmol/m(3) NaCl. During localized corrosion, the current and potential were changed, with fluctuations and the potential and the current fluctuations show good correlation. The slope of the PSD spectra of both types of anodized specimens are about minus one (-1), just after localized corrosion started. This technique allows observation of electrochemical impedance changes during localized corrosion. The impedance spectra are independent of signal frequency and the impedance of porous types anodic oxide film specimens decrease with immersion time and increases with anodizing time.
  • フォトンラプチャー法による中性塩化物溶液中におけるZn系めっき鋼板の局部溶解挙動(表面処理・腐食)
    坂入 正敏, 板橋 一馬, 内田 義孝, 高橋 英明
    鐵と鋼 : 日本鐡鋼協會々誌, 92, 2, 68, 74, 社団法人日本鉄鋼協会, 2006年02月, [査読有り]
    日本語, A photon rupture method, film removal by a focused one pulse of pulsed Nd-YAG laser beam irradiation, has been applied to investigate initial stage of localized dissolution of Zn and Zn-Al alloy coated steels, which were formed nitrocellulose films as a protective film, in 0.5 kmol m^<-3> H_3BO_3-0.05 kmol m^<-3> Na_2B_4O_7 (pH=7.4) with 0.01 kmol m^<-3> chloride ions. This method can remove oxide films and nitrocellulose films on coated layer by laser ablation without any contamination from film removing tools, and the removing speed is extremely high. At low applied potentials, all sample...
  • Localized dissolution of Zn-Al alloy coated steel in neutral solution with Cl- by photon rupture method
    M Sakairi, K Itabashi, Y Utida, H Takahashi
    TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN, 92, 2, 16, 22, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2006年02月, [査読有り]
    日本語, 研究論文(学術雑誌), A photon rupture method, film removal by a focused one pulse of pulsed Nd-YAG laser beam irradiation, has been applied to investigate initial stage of localized dissolution of Zn and Zn-Al alloy coated steels, which were formed nitrocellulose films as a protective film, in 0.5kmol m(-3) H3BO3-0.05kmol m(-3) Na2B4O7 (pH = 7.4) with 0.01 kmol m(-3) chloride ions. This method can remove oxide films and nitrocellulose films on coated layer by laser ablation without any contamination from film removing tools, and the removing speed is extremely high. At low applied potentials, all samples reformed oxide film after films were removed by this method. The oxide film formation kinetics follows on inverse logarithmic law in agreement with Cabrera-Mott theory. However, as increasing applied potential, after some period, localized dissolution occur at nitrocellulose films were removed area. The peak currents of Zn-5mass%Al coated steel specimens were larger than those of Zn and Zn-5mass%Al coated specimens. This result suggest that high aluminum containing coated layer does not show good corrosion resistance in frequently oxide film removal environments.
  • Blister and pit formation during cathodic polarization of aluminum covered with anodic oxide films - In-situ AFM observation               
    S. Kurokawa, Z. Kalo, T. Kikuchi, M. Sakairi, H. Takahashi
    Proceedings - Electrochemical Society, PV 2004-19, 447, 462, 2006年
    英語, 研究論文(国際会議プロシーディングス), Highly pure aluminum specimens covered with barrier type anodic oxide films were cathodically polarized with constant currents in a neutral borate solution, and the change in the surface morphology of the specimen during cathodic polarization was examined by in-situ atomic force microscopy as well as scanning electron microscopy and confocal scanning laser microscopy. It was found that, at the first stage of cathodic polarization, the formation and growth of blisters take place, and that, at the second stage, the blisters are destructed to form pits on the aluminum substrate. Mechanisms on the pit formation are discussed in terms of hydrogen evolution at the interface between anodic oxide films and the aluminum substrate, and corrosion by local alkalization.
  • Fabrication of electrochemical micro-reactor by photon rupture method and electrochemistry               
    Masatoshi Sakairi, Masashi Yamada, Hideaki Takahashi
    Proceedings - Electrochemical Society, PV 2004-19, 359, 370, 2006年
    英語, 研究論文(国際会議プロシーディングス), Photon rupture with a focused single pulse of pulsed YAG-laser irradiation was used to fabricate electrochemical micro-reactor. Porous type anodic oxide film formed specimens were irradiated in solutions with a pulsed Nd-YAG laser beam through a convex lens to fabricate micro channels, micro-electrode and through holes for solution inlet and outlet. During irradiation, specimens were moved by computer controlled XYZ stage. After irradiation, surface of micro-channel and through hole were formed oxide film and it of micro-electrode was formed Au layer by electrochemically. Calculated volume of the micro-reactor including micro-channel and through holes is about 1.5 μl. A cyclic voltammogram of the micro-electrochemical cell was measured in 2 mol/m 3 and 20 mol/m3 K3Fe(CN)6 / K 4Fe(CN)6 at static condition at different scanning rate. Anodic and cathodic peak current were measured and these values were depended on scanning rate and ions concentration.
  • フォトンラプチャー法による中性塩化物溶液中におけるZn系めっき鋼板の局部溶解挙動
    坂入正敏, 板橋一馬, 内田義孝, 高橋英明
    鉄と鋼, 92, 2, 16, 22, 社団法人日本鉄鋼協会, 2006年
    日本語, A photon rupture method, film removal by a focused one pulse of pulsed Nd-YAG laser beam irradiation, has been applied to investigate initial stage of localized dissolution of Zn and Zn-Al alloy coated steels, which were formed nitrocellulose films as a protective film, in 0.5 kmol m^<-3> H_3BO_3-0.05 kmol m^<-3> Na_2B_4O_7 (pH=7.4) with 0.01 kmol m^<-3> chloride ions. This method can remove oxide films and nitrocellulose films on coated layer by laser ablation without any contamination from film removing tools, and the removing speed is extremely high. At low applied potentials, all samples reformed oxide film after films were removed by this method. The oxide film formation kinetics follows on inverse logarithmic law in agreement with Cabrera-Mott theory. However, as increasing applied potential, after some period, localized dissolution occur at nitrocellulose films were removed area. The peak currents of Zn-5mass%Al coated steel specimens were larger than those of Zn and Zn-5mass%Al coated specimens. This result suggest that high aluminum containing coated layer does not show good corrosion resistance in frequently oxide film removal environments.
  • Initial stage of localized corrosion in artificial pits formed with photon rupture on 55mass%Al-Zn coated steels
    Masatoshi Sakairi, Yoshiyuki Uchida, Hideaki Takahashi
    ISIJ INTERNATIONAL, 46, 8, 1218, 1222, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2006年, [査読有り]
    英語, 研究論文(学術雑誌), The photon rupture method, whose oxide film and metal are removed by focused pulsed Nd-YAG laser beam irradiation was applied to form artificial micro pits in 55 mass% aluminum-zinc coated steels. The 15 mu m coated layer was removed by 2 s of continuous laser irradiation in this experiment. The rest potential transients were measured during the laser irradiation. While the coated layer covered the steel substrate, the rest potential change in the negative direction just after the starts of the laser irradiation and then returned to the previous value. However, after the steel substrate was exposed to solution, the rest potential moved in the positive direction immediately after the discontinuation of the laser irradiation and then also returned to the previous value. The amplitude and duration of the potential changes after the laser irradiation increased with longer irradiation, related to the pit depth and exposed area ratio of coated layer/steel substrate. These rest potential fluctuation differences can be explained by galvanic reaction changes in the artificial pit formed on the coated steel during irradiation.
  • Initial stage of localized corrosion in artificial pit formed on zinc coated steels by photon rupture
    Sakairi Masatoshi, Uchida Yoshiyuki, Takahashi Hideaki
    Passivation of Metals and Semiconductors, and Properties of Thin Oxide Layers, 561, 566, Elsevier, 2006年, [査読有り]
    英語, 論文集(書籍)内論文, This chapter presents a study in which photon rupture method, and oxide film and metal removal by focused pulsed Nd - YAG laser beam irradiation, is applied to form an artificial micro pit in zinc coated steels. The zinc coated steel sheets were cut into 20 x 20 mm coupon and after cleaning ultrasonically, samples were dipped in nitrocellulose / ethyl acetate solution two times to form an approximately 30 μm thick protective nitrocellulose film on the samples. It takes about 2 s to remove the zinc coated layer with a thickness of about 20 μm by continuance laser irradiation in this experiments. The rest potential transient was measured during laser irradiation. During zinc covered on the steel substrate, the rest potential was changed to noble direction just after laser was irradiated and then returned to previous value. However, after the steel substrate was exposed to the solution, the rest potential move to positive direction just after laser was irradiated and then returned to previous value. The amplitude and duration of the potential change after laser irradiation increased with increasing irradiation period which is related to pit depth and exposed area ratio of zinc / steel substrate. These rest potential fluctuation difference can be explained by the galvanic reaction change in the artificial pit formed on zinc coated steels during irradiation. © 2006 Elsevier B.V. All rights reserved.
  • 電気泳動を用いたゾル-ゲル被覆/陽極酸化によるアルミニウムへのAl-Si複合酸化皮膜の作製
    H.Takahashi, M.Sunada, T.Kikuchi, M.Sakairi, S.Hirai
    Passivation of Materials and Semiconductors, and Thin Oxide Layers,, 685, 690, 2006年, [査読有り]
    英語
  • The growth and electrical transport properties of self-organized metal/oxide nanostructures formed by anodizing Ta-Al thin-film bilayers
    A Mozalev, G Gorokh, M Sakairi, H Takahashi
    JOURNAL OF MATERIALS SCIENCE, 40, 24, 6399, 6407, SPRINGER, 2005年12月, [査読有り]
    英語, 研究論文(学術雑誌), Anodizing of Ta-Al metal bilayers (Al on Ta) sputter-deposited onto SiO2 substrates was performed in oxalic acid electrolytes at anode potentials of 53 to 21.5 V in order to form nanoporous alumina layers and sequentially oxidize the tantalum underlayers through the alumina pores. The films formed consist of arrays of tantalum oxide nanohillocks percolating through the residual tantalum layer down to the substrate, so that a self-organized network of tantalum nanowires forms between the substrate and the alumina film. The average width (25-<10 nm), length (70-35 nm), and population density (10(9)-10(11) cm(-2)) of the nanowires are systematically defined by the initial tantalum thickness (8-22 nm) and the anodizing conditions. The mesh-like, nano-sized morphologies of the tantalum underlayers result in a remarkably wide range of potential-dependent, controlled electrical sheet resistances (10(2)-10(7) (ohm)/sq). The periodical, tunable, metal/insulator film structure, allowing an increased transition to hopping or tunneling conduction at elevated temperature, leads to negative temperature coefficients of resistance, ranging 300 to 5 ppm/K. Oscillations of the potential-dependent dc conductance registered in the films at room temperature are attributed to the quantum-size effects in the metal/oxide nanostructures. The films are of technological importance for fabrication of thin-film, planar, adjustable resistors with significantly improved performances. (c) 2005 Springer Science + Business Media, Inc.
  • The initial stage of pitting corrosion on coated steels investigated by photon rupture in chloride containing solutions
    M Sakairi, Y Uchida, K Itabashi, H Takahashi
    CORROSION SCIENCE, 47, 10, 2461, 2469, PERGAMON-ELSEVIER SCIENCE LTD, 2005年10月, [査読有り]
    英語, 研究論文(学術雑誌), A photon rupture method, film removal by a focused pulse of pulsed Nd-YAG laser beam irradiation, has been developed to enable oxide film stripping at extremely high rates without contamination from the film removal tools. In the present study, Zn-55mass%Al alloy and Al-9mass%Si alloy-coated steel specimens covered with protective nitrocellulose film were irradiated with a focused pulse of a pulsed Nd-YAG laser beam at a constant potential in 0.5 kmol m(-3) H3BO3-0.05 kmol m(-3) Na2B4O7 (pH = 7.4) with 0.01 kmolm(-3) of chloride ions to investigate the initial stage of localized corrosion. At low potentials, oxide films on both coated alloys were reformed after the nitrocellulose films were removed by this method. The oxide film formation kinetics follows an inverse logarithmic law, in agreement with Cabrera-Mott theory. However, at high potentials, localized corrosion producing corrosion products occurs at the area where nitrocellulose film was removed. Nevertheless, when the applied potential is less noble, the dissolution current of the Zn-55mass%Al-coated steel samples is higher than that of Al-9mass%Si-coated samples. (c) 2005 Elsevier Ltd. All rights reserved.
  • Anodic film growth on Al layers and Ta-Al metal bilayers in citric acid electrolytes
    A Mozalev, Mozaleva, I, M Sakairi, H Takahashi
    ELECTROCHIMICA ACTA, 50, 25-26, 5065, 5075, PERGAMON-ELSEVIER SCIENCE LTD, 2005年09月, [査読有り]
    英語, 研究論文(学術雑誌), A systematic investigation has been undertaken of anodising behaviour of aluminium in citric acid solutions under changing the current density, electrolyte temperature, concentration and stirring conditions. Porous films of steady-state, controlled and extraordinary large morphologies have been obtained at the formation voltages of 260-450 V. The barrier layer thickness, cell and pore diameters appeared to be directly proportional to the formation voltage. For the first time, a porous anodic film with cell diameter of 1.1 mu m, barrier layer thickness of 0.5 mu m and pore diameter of 0.23 mu m was naturally grown on aluminium in 0.125 mol dm(-3) citric acid electrolyte. The selected electrical and electrolytic conditions have been applied to sputter-deposited Ta-Al bilayers. The tantalum underlayer was anodised through the initially grown at 450 V porous alumina film with the formation of tantalum oxide 'columns' penetrating into the pores and mixing with the outer part of the alumina cell walls. During subsequent constant current reanodising of the Ta-Al bilayers in 0.5 mol dm(-3) H3BO3, the voltage rose up to 1100 V, until voltage fluctuations terminated normal oxide growth. The columns thickened uniformly up to 1.42 mu m with the nm V-1 ratio of 1.3, exhibiting nearly ideal dielectric behaviour up to almost 1000 V of the formation voltage. The outer column material is composed mainly of stoichiometric Ta2O5 mixed with small amount of Al2O3, while the innermost column material is tantalum monoxide with little content of boron species. Implications of these findings for the formation of composite dielectrics for high-voltage electrolytic capacitors are discussed. (C) 2005 Elsevier Ltd. All rights reserved.
  • Electrochemical noise study on galvanic corrosion of anodized aluminum in chloride environments               
    Masatoshi Sakairi, Ukiya Shimoyama, Hideaki Takahashi
    Proceedings - Electrochemical Society, PV 2004-14, 265, 272, 2005年
    英語, 研究論文(国際会議プロシーディングス), Aluminum and aluminum alloys are usually used after surface treatment, namely anodizing which formed a barrier type or a porous type oxide film. The effect of the anodic oxide film structure on galvanic corrosion of aluminum was examined by electrochemical noise analysis technique in chloride ion containing solutions. As the thickness of both types of anodic oxide film increased, the incubation period of localized corrosion became longer. The power spectrum density of potential and impedance of electrochemical noise decreased with immersion time. The impedance of porous type anodic oxide films were larger than that of the barrier type anodic oxide film.
  • Analysis of the initial stage of localized corrosion on Zn and Zn alloy coated steels by photon rupture method
    M Sakairi, K Itabashi, H Takahashi
    ISIJ INTERNATIONAL, 45, 1, 71, 76, IRON STEEL INST JAPAN KEIDANREN KAIKAN, 2005年, [査読有り]
    英語, 研究論文(学術雑誌), A photon rupture method, film removal by a focused pulse of pulsed Nd-YAG laser beam irradiation, has been developed as it enables oxide film stripping at extremely high rates without contamination from the film removal tools. In the present study, Zn and Zn-5mass%Al alloy coated steel specimens covered with protective nitrocellulose film were irradiated with a focused pulse of a pulsed Nd-YAG laser beam at a constant potential in 0.5 kmol m(-3) H3BO3-0.05 kmol m(-3) Na2B4O7 (pH=7.4) with/without 0.05 kmol m(-3) of chloride ions to investigate the initial stage of localized corrosion. At low potentials, both samples reformed oxide film after the nitrocellulose films were removed by this method. The oxide film formation kinetics of Zn-55mass%Al follow an inverse logarithmic law, in agreement with Cabrera-Mott theory. However, at high potentials, localized corrosion producing corrosion products occured at the area where nitrocellulose film was removed. The dissolution current of the Zn coated steel samples is higher than that of Zn-5mass%Al coated samples at the same applied potential.
  • Initial stage of localized corrosion on titanium in phosphate buffer solutions by photon rupture
    Masatoshi Sakairi, Hiroomi Miyata, Hideaki Takahashi
    ECS Transactions, 1, 4, 183, 194, 2005年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), A photon rupture method, by which oxide film can be removed by focused, pulsed Nd-YAG laser beam irradiation, applied to investigate localized repair of passive oxide films of titanium. The specimens were irradiated with a focused pulse of a pulsed Nd - YAG laser beam at a constant potential in 8.1 mol/m 3 Na2HPO4/ 5 mol/m3 KH 2PO4 solutions with 140 mol/m3 NaCl + 50 mol/m3 KCl (PBS) or with different chloride concentrations, and the current transients were monitored. The current increases with increasing applied potential and chloride concentration. The oxide film, however, repairs in all experimental conditions. The oxide film formation kinetics did not follow the inverse logarithmic law according to Cabrera-Mott theory. copyright The Electrochemical Society.
  • ニオブアノード酸化皮膜の構造および誘電的性質に与える電流密度の影響
    長原 和宏, 坂入 正敏, 高橋 英明, 永田 晋二, 松本 和芳, 高山 幸一, 小田 幸男
    表面技術 = The Journal of the Surface Finishing Society of Japan, 55, 12, 943, 951, 一般社団法人 表面技術協会, 2004年12月, [査読有り]
    日本語, 研究論文(学術雑誌), Niobium specimens with chemical polishing were anodized in a phosphoric acid solution galvanostatically at ia,ini=1, 10, 100 and 1000Am−2 up to Ea=100V, and then potentiostatically at Ea=100V for tpa=7.2ks. During galvanostatic anodizing, the anode potential increased almost linearly with time on all the specimens, while, during potentiostatic anodizing, the anodic current decreased with time. The current density at tpa=7.2ks was higher at lower ia,ini in the range of 0.02 to 0.25Am−2. The spectra of Rutherford backscattering spectroscopy (RBS) and glow discharge optical emission spectrosco...
  • 定電位アノード酸化時におけるニオブアノード酸化皮膜の構造および誘電的性質の変化
    長原 和宏, 坂入 正敏, 高橋 英明, 松本 和芳, 高山 幸一, 小田 幸男
    電気化学および工業物理化学 : denki kagaku, 72, 9, 624, 632, 電気化学会, 2004年09月, [査読有り]
    英語, 研究論文(学術雑誌), Niobium specimens with chemical polishing were anodized in a phosphoric acid solution galvanostatically up to E-a = 100 V, and then potentiostatically at E-a = 100 V. During galvanostatic anodizing, anode potential increased almost linearly with time, while, during potentiostatic anodizing, anodic current decreased with time before t(pa) = 3.6 ks, and then increased slowly before decreasing again at t(pa) = 32.4 ks. Galvanostatic anodizing allowed compact oxide films to grow at a steady rate, and also micro imperfections to form in the film at the ridge of convex network structure produced by chemical polishing. The imperfections grew during potentiostatic anodizing, showing the cracking and rolling-up of the oxide film as well as the formation of crystalline oxide at the center of the imperfections. Long-term anodizing lead to the coalescence of the imperfections and eventually the coveting of all surfaces with imperfections. Parallel equivalent capacitance, C-p, of anodic oxide films decreased with tpa before 3.6 ks, and increased after 3.6 ks, while the dielectric dissipation factor, tan delta, remained to a small value before 3.6 ks, and increased with tpa after 3.6 ks. Measurements with higher bias voltages caused less dielectric dispersion of anodic oxide films. The mechanism of structural change of anodic oxide films during potentiostatic anodizing, and the correlation between the structure and dielectric properties of anodic oxide films are discussed.
  • ゾル・ゲルコーティング/アノード酸化によるAl-Nb複合酸化物皮膜の形成
    渡辺 恵司, 坂入 正敏, 高橋 英明, 永田 晋二, 平井 伸治
    表面技術 = The Journal of the Surface Finishing Society of Japan, 55, 7, 471, 477, 一般社団法人 表面技術協会, 2004年07月, [査読有り]
    日本語, 研究論文(学術雑誌), Aluminum specimens coated with niobium oxide by a sol-gel method were galvanostatically anodized in a neutral borate solution. The time-variations in anode potential during anodizing were monitored, and the structure and dielectric properties of the anodic oxide film were studied by TEM, EDX, RBS, and electrochemical impedance measurements.It was found that the anode potential increases linearly with time after a rapid increase in potential at the initial period of anodizing. During anodizing, an anodic oxide film, which consisted of an inner Al2O3 layer and an outer Al-Nb composite oxide l...
  • パルスYAGレーザー照射によるAl硬質アノード酸化皮膜の局部除去挙動
    坂入 正敏, 山下 新吾, 高橋 英明, 嶋村 清隆, 片山 直樹, 阿部 芳彦
    表面技術 = The Journal of the Surface Finishing Society of Japan, 55, 5, 349, 354, 一般社団法人 表面技術協会, 2004年05月, [査読有り]
    日本語, 研究論文(学術雑誌), A laser beam micro surface finishing method attempted to remove hard anodic oxide film formed on aluminum specimens. The hardness of the film increases with increasing applied current density during anodizing and decreasing concentration of SO42− ions. Specimens were irradiated in solutions with a pulsed Nd-YAG laser beam through a convex lens with 60mm focal length to remove anodic oxide film locally. Thin anodic oxide film can be removed without cracks by one pulse of laser irradiation, but thick oxide films need several pulses of irradiation removed without cracks. Thick as grown hard an...
  • Structure, morphology, and dielectric properties of nanocomposite oxide films formed by anodizing of sputter-deposited Ta-Al bilayers
    A Mozalev, M Sakairi, H Takahashi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 151, 11, F257, F268, ELECTROCHEMICAL SOC INC, 2004年, [査読有り]
    英語, 研究論文(学術雑誌), Anodizing of Ta-Al bilayers (aluminum deposited on tantalum) was performed in 0.2 M H2C2O4 solution to transform the aluminum metal into its nanoporous oxide followed by pore widening and reanodizing to different voltages in the range of 100-600 V. The anodic films consist of an upper layer of nano-sized tantala columns penetrating into the pores and a lower layer of continuous tantalum oxide under the porous alumina film. The columns are mainly composed of tantalum pentoxide and tantalum sub-oxides TaO2, Ta2O3, and TaO while the lower film layer is tantalum monoxide. At the boundary between the columns and alumina cells, a region of mixed (composite) Ta2O5 and Al2O3 is formed due to channeling of the ionic current through the outer part of the alumina cell walls. The relationship between the layers and the ionic transport during oxide growth depend on pore size and formation voltage. The dielectric properties of the anodic films are close to those of an ideal capacitor. Voltage-independent apparent dielectric constant of 12.6 was determined for the films formed by normal reanodizing. The relatively higher dielectric constant for the films formed by reanodizing through the widened pores rises from 17.6 to 24.0 in the voltage range of 270-400 V, which is due to the change in morphology, relative amount and chemical composition of anodic tantala in the complex film structure. The nanocomposite anodic films can be used as dielectrics for high-voltage low-leakage current electrolytic capacitors. (C) 2004 The Electrochemical Society.
  • Behavior of second-phase particles in Al5052 alloy during anodizing in a sulfuric acid solution - CSLM observation
    SM Moon, M Sakairi, H Takahashi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 151, 7, B399, B405, ELECTROCHEMICAL SOC INC, 2004年, [査読有り]
    英語, 研究論文(学術雑誌), The behavior of second-phase particles during anodizing of Al5052 alloy in 16 wt% sulfuric acid solution was investigated by confocal scanning laser microscopy (CSLM). Two different types of second-phase particles were observed in the Al5052 alloy, Al-Mg particles and Al-Mg-Fe particles. The Al-Mg particles showed a groove-type morphology because of selective dissolution of Mg during anodizing, while Al-Mg-Fe particles showed a protrusion-type morphology in the CSLM height image (top view). The CSLM contrast image of cross sections of the anodic oxide film showed the presence of two different types of imperfections in the anodic oxide film, bright- and dark-type imperfections. The bright-type imperfections were determined to contain metallic iron, indicating that the metallic iron had been transferred from the substrate into the oxide film without oxidation during anodizing; this reflects the incident laser beam strongly to give a bright CSLM contrast image. The dark-type imperfections were explained by a scattering of the laser beam with vacant or irregularly structured regions, resulting from the selective dissolution of Mg. (C) 2004 The Electrochemical Society.
  • フォトンラプチャー法による厚いアルミニウムアノード酸化皮膜の局部除去と局部金属析出 (E)
    坂入 正敏, 加藤 善大, Chu 松竹, 高橋 英明, 阿部 芳彦, 片山 直樹
    電気化学および工業物理化学 : denki kagaku, 71, 11, 920, 926, 電気化学会, 2003年11月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum specimens covered with thick porous type anodic oxide films, up to 100 mum, were irradiated by a photon rupture technique, a focused pulsed Nd-YAG laser beam, in a Ni2+ solution. The thick anodic oxide films, which does not dyed, were ruptured with numerous cracks by laser ablation. However, dyed thick anodic oxide films were removed layer by layer without developing cracks, as the dyed oxide film absorbed the laser energy. After laser irradiation, electroplating was attempted to form thick Ni layers at only the irradiated area. By this local electroplating, a Ni layer was found to deposit just at the irradiated area, as the pore sealed anodic oxide films acted as an insulating film.
  • Application of CSLM to the surface morphological study of al 5052 alloy anodized in sulfuric acid solution
    SM Moon, M Sakairi, H Takahashi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 150, 10, B473, B480, ELECTROCHEMICAL SOC INC, 2003年10月, [査読有り]
    英語, 研究論文(学術雑誌), Confocal scanning laser microscopy (CSLM) was applied to the surface morphological study of the anodic oxide film-covered Al5052 alloy. "Contrast" and "height" images of the specimens were obtained by scanning the laser beam in the x, y, and z directions. The incident laser beam appeared to be reflected by either the outer oxide surface, imperfections in the oxide film, or the inner oxide/metal interface. Contrast images of the outer oxide surface and the metal/oxide interface were obtained separately by choosing different scanning ranges of the focused z point of the incident laser beam. Two different types of imperfections, bright and dark, were observed in the contrast images of CSLM. The bright imperfections may correspond to inclusions with high reflectivity, and the dark ones to inclusions with uneven surfaces. The z position of the bright imperfections in the oxide film was determined by analyzing the height images. (C) 2003 The Electrochemical Society.
  • Nucleation and growth of the nanostructured anodic oxides on tantalum and niobium under the porous alumina film
    A Mozalev, M Sakairi, Saeki, I, H Takahashi
    ELECTROCHIMICA ACTA, 48, 20-22, 3155, 3170, PERGAMON-ELSEVIER SCIENCE LTD, 2003年09月, [査読有り]
    英語, 研究論文(学術雑誌), Anodic oxidation of Ta-Al (aluminium deposited on tantalum) and Nb-Al (aluminium deposited on niobium) has been performed in organic and inorganic acid electrolytes for porous alumina formation. Arrays of tantalum nanoscale oxide 'hillocks' and niobium oxide 'goblets' derived from the anodised Ta-Al and Nb-Al bilayer samples have been investigated by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy depth profiling. Anodising proceeds in the sequence of growth of porous anodic alumina and, when the aluminium layer is consumed up to the underlying metal, growth of anodic tantalum (niobium) oxide under the bottoms of the alumina pores. The oxidation of the underlying metal results from metal ions migrating outward and oxygen ions transported through, and released from, the alumina barrier layer, which dissolves at the tantala/alumina interface, i.e. without tantalum being in direct contact with the electrolyte. The shape and mutual arrangement of the anodic oxide nanostructures depend on the nature of the underlying metal. anodising solution. and are consistent with the difference between the resistivities of the tantalum (niobium) oxide formed and the barrier layer of the overlying alumina cells, which is influenced by incorporated electrolyte-derived species. (C) 2003 Elsevier Ltd. All rights reserved.
  • Three-dimensional Microstructure Fabrication with Aluminum Anodizing, Laser Irradiation, and Electrodeposition
    T. Kikuchi, M. Sakairi, H. Takahashi
    Journal of the Electrochemical Society, 150, 9, C567, C572, 2003年09月, [査読有り]
    英語, 研究論文(学術雑誌), Three-dimensional microstructures made of Ni metal or acrylic resin were fabricated by five sequential processes: porous anodic oxide film formation, pore sealing, laser irradiation, Ni electroplating or electrophoretic deposition of acrylic resin, and removal of the aluminum substrate and anodic oxide films. Cylindrical and prismatic aluminum rods were anodized in an oxalic acid solution to form porous-type anodic oxide films, and then immersed in boiling distilled water for pore sealing. The anodized and pore-sealed specimens were irradiated with a pulsed neodymium-doped yttrium aluminum garnet (Nd-YAG) laser beam in a Ni plating solution or doubly distilled water to remove anodic oxide film locally by rotating and moving up/down with an XYZθ stage. Nickel or acrylic resin was deposited at the area where film had been removed by cathodic or anodic polarization in the solution before removing the aluminum substrate and anodic oxide films in NaOH solutions. Cylindrical and prismatic network cages, rings, springs, and bellows made of Ni metal or acrylic acid resin were fabricated successfully. © 2003 The Electrochemical Society. All rights reserved.
  • Nanopatterning on aluminum surfaces with AFM probe
    Z Kato, M Sakairi, H Takahashi
    SURFACE & COATINGS TECHNOLOGY, 169, 195, 198, ELSEVIER SCIENCE SA, 2003年06月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum specimens covered with anodic oxide films were scratched with a silicon probe tip of atomic force microscope in pure water. CuSO4, solutions, Cu-electroless plating solutions and diluted NaOH solutions. The rate of groove development (R-gd) was in the order NaOH>CuSO>pure water>Cu-electroless solution, and increased with increasing probe load and scratch number. Wear of the silicon probe tip was also examined by scratching many times in pure water and NaOH solution. It was Greater in NaOH solution than in pure water. A silicon tip coated with polycrystalline diamond showed a high processing capability and wear resistance. (C) 2003 Elsevier Science B.V. All rights reserved.
  • Fabrication of independent nickel microstructures with anodizing of aluminum, laser irradiation, and electrodeposition
    T Kikuchi, M Sakairi, H Takahashi
    JOURNAL OF UNIVERSITY OF SCIENCE AND TECHNOLOGY BEIJING, 10, 3, 39, 42, JOURNAL OF UNIV OF SCIENCE AND TECHNOLOGY BEIJING, 2003年06月, [査読有り]
    英語, 研究論文(学術雑誌), Independent microstructures made of Ni metal were fabricated by five sequential processes: porous anodic oxide film formation, pore sealing, laser irradiation, Ni electroplating, and removal of the aluminum substrate and anodic oxide films. Aluminum plates and rods were anodized in an oxalic acid solution to form porous type anodic oxide films, and then immersed in boiling distilled water for pore sealing. The anodized and pore-sealed specimens were irradiated with a pulsed neodymium-doped yttrium aluminum garnet (Nd-YAG) laser beam in a Ni plating solution to remove anodic oxide film locally by rotating and moving up / down with an XYZtheta-stage. Nickel was deposited at the area where film had been removed by cathodic polarization in the solution before removing the aluminum substrate and anodic oxide films in NaOH solutions. Cylindrical or plain network structures were fabricated successfully.
  • アルミニウムおよびAl5052合金上生成したアノード酸化皮膜中に存在する欠陥を通してのNi-P析出
    文 聖模, 坂入 正敏, 高橋 英明, 嶋村 清隆
    電気化学および工業物理化学 : denki kagaku, 71, 4, 260, 265, 電気化学会, 2003年04月, [査読有り]
    英語, 研究論文(学術雑誌), The present investigation examined how to prevent Ni-P deposition through imperfections in anodic oxide films on aluminum and Al5052 alloy during electroless-plating. Pure aluminum and Al5052 alloy specimens were anodized in a sulfuric acid solution to form porous oxide films, and then immersed in boiling water to seal the pores. Confocal scanning laser microscopy was applied to examine the effect of pore-sealing on the Ni-P electroless deposition through imperfections. There were Ni-P domes deposited on both pure aluminum and Al5052 alloy covered with anodic oxide films through the imperfections in the oxide film. The number of Ni-P domes increased with electroless plating time on both kinds of specimens, and this change was more remarkable on Al5052 alloy, due to imperfections originating from second phase particles in the alloy substrate. Sealing treatment effectively prevented Ni-P dome deposition on both types of specimens, due to healing of the imperfections in the oxide films. Longer anodizing before the sealing treatment prevented the Ni-P deposition completely on the Al5052 alloy specimen even after 15 h of electroless plating.
  • ゾル・ゲル法によりSiO_2 を被覆したアルミニウムのアノード酸化 : 新規な高耐電圧アノード酸化皮膜の作製
    渡辺 恵司, 坂入 正敏, 高橋 英明, 平井 伸治
    表面技術 = The Journal of the Surface Finishing Society of Japan, 54, 3, 235, 240, 一般社団法人 表面技術協会, 2003年03月, [査読有り]
    日本語, 研究論文(学術雑誌), Aluminum specimens were covered with SiO2 film by a sol-gel coating and then anodized galvanostatically in a boric acid solution. Time variations in the anode potential during anodizing were monitored, and the structure and dielectric properties of anodic oxide films were examined by TEM-EDX, and electrochemical impedance measurements. It was found that anodizing of aluminum coated with SiO2 films leads to the formation of anodic oxide films that consist of an outer Al-Si composite oxide layer and an inner Al2O3 layer at the interface between the SiO2 film and the metal substrate. The break...
  • アルミニウムのアノード酸化とレーザー照射を用いた微細プリント配線板の作製 : パターン形成における酸化皮膜の厚さの影響
    菊地 竜也, 坂入 正敏, 高橋 英明, 阿部 芳彦, 片山 直樹
    表面技術 = The journal of the Surface Finishing Society of Japan, 54, 2, 137, 144, 一般社団法人 表面技術協会, 2003年02月, [査読有り]
    日本語, 研究論文(学術雑誌), An aluminum specimen covered with porous type oxide films with 3 to 54μm thickness was irradiated by a pulsed Nd-YAG laser through a convex lens with 20 mm focal length in a solution to examine the mode of oxide film removal by laser irradiation. A prototype printed circuit board was fabricated using laser irradiation and Au electroplating. Thin oxide films were removed instantaneously after laser irradiation onset by the laser ablation mechanism. Thick oxide films were destructed initially from the upper part of the oxide films by the thermal shock mechanism, and then by the laser ablation...
  • Initial stage of localized corrosion on Zn - 5 mass% Al alloy coated steels by pulsed photon film removal technique               
    Masatoshi Sakairi, Kazuma Itabashi, Hideaki Takahashi
    Journal of Corrosion Science and Engineering, 6, 2003年
    英語, 研究論文(国際会議プロシーディングス), A pulsed photon film removal technique, film removal by a focused one pulse of pulsed Nd-YAG laser beam irradiation, has been developed since it enables the oxide film stripping at extremely high rate without any contamination from film removal tools. In the present investigation, Zn, Zn-5 mass% Al and Zn-55 mass% Al alloy coated steel specimens covered with protective nitrocellulose film were irradiated with a focused one pulse of pulsed Nd - YAG laser beam at a constant potential in 0.1 kmol / m3 Na2B 4O77 (pH = 9.4) solutions with / without chloride ions to monitor the current transient. Irradiation with a pulsed laser in solutions causes abrupt removal of the nitrocellulose film on the specimens at the laser-irradiated area. Without chloride ions, oxide films were reformed in the solutions at 1 V. However, in chloride ion containing solutions, localized corrosion of coated layers occurs at high potentials, while film reformation occurs at low potentials. It was also found that chloride ions enhance dissolution of aluminum and zinc at the very initial period after laser irradiation. For long time polarization after laser irradiation in chloride ions containing solutions, corrosion products formed on nitrocellulose film removed area.
  • アルミニウムアノード酸化/AFM加工を用いる微細パターン作製法
    加藤 善大, 坂入 正敏, 高橋 英明
    材料と環境 : zairyo-to-kankyo, 52, 1, 12, 17, 腐食防食協会, 2003年, [査読有り]
    日本語, 研究論文(学術雑誌), Aluminum specimen covered with thin barrier type anodic oxide films was scratched with Si tip of AFM probe in a CuSO4 solution, and then cathodically polarized in the solution, using the Si tip as a counter electrode. During AFM probe scratching, oscillation of current was observed and decreased with scratching time. Analysis of the current oscillation enabled to examine the proceeding of the removal of anodic oxide films during AFM probe scratching. Silicon tip wore easily by scratching the oxide film-covered aluminum with a force. After AFM probe scratching, cathodic polarization of aluminum specimen caused the Cu deposition only at the film removed area, using a nitrocellulose film-coated Si tip as a counter electrode.
  • ポアーフィリング法によるアルミニウムアノード酸化皮膜のブレークダウン電位上昇の試み
    島田 英樹, 坂入 正敏, 高橋 英明
    表面技術 = The journal of the Surface Finishing Society of Japan, 53, 2, 142, 148, 社団法人 表面技術協会, 2002年02月, [査読有り]
    日本語, 研究論文(学術雑誌), Aluminum covered with porous anodic oxide films was re-anodized in 0.5 kmolm-3-H3BO3 and 5×10-5kmolm-3-KOH solutions to examine the formation and breakdown of the oxide film.In H3BO3-solution, the pores were filled with new oxide during re-anodizing, resulting in the uniform thickening of the barrier layer until film breakdown started. The breakdown potential of the film formed by the “pore-filling” method was 200V higher at maximum than that formed by anodizing after electropolishing.In KOH solution, the pore-filling with new oxide was accompanied by local dissolution of oxide film, leadin...
  • 低濃度KOH溶液中におけるアルミニウムアノード酸化皮膜の生成挙動
    島田 英樹, 坂入 正敏, 高橋 英明
    表面技術 = The journal of the Surface Finishing Society of Japan, 53, 2, 134, 141, 社団法人 表面技術協会, 2002年02月, [査読有り]
    日本語, 研究論文(学術雑誌), Aluminum was anodized in diluted KOH solutions galvanostatically to examine the effect of KOH-concentration on the growth and breakdown of anodic oxide films. Time-variations in the anode potential, Ea, the amount of dissolved Al3+ ions, and electroluminescence intensity were measured during anodizing, and the film structure was observed by transmission electron microscopy and scanning electron microscopy.At 5×10-5 and 5×10-4M, Ea increased with time linearly at the initial stage, and the rate of increase in Ea decreased at 400V. The slow increase in Ea stopped at about 600V, and beyond the...
  • Fabrication of grooves on aluminum surface with atomic force microscope probe processing
    Z Kato, M Sakairi, H Takahashi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 148, 12, C790, C798, ELECTROCHEMICAL SOC INC, 2001年12月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum specimens covered with anodic oxide films were scratched with an atomic force microscope (AFM) probe in air, pure water, CuSO4 solutions, Cu-electroless plating solution, and diluted NaOH solutions to examine the effect of the probe load, scratch number, and processing environment on the rate of groove development. The rest potential of the aluminum was monitored during scratching in the solutions, and in situ AFM observations were carried out after the scratching. Probe wear was also examined in pure water and NaOH solution. The rate of groove development was in the order NaOH > CuSO4 > air > purewater > Cu-electroless solution, and decreased with decreasing probe load and increasing scratch number. The rest potential remained steady in the solutions during scratching with loads below 12.5 muN, while it dropped rapidly above 25 muN. Copper was deposited in and around grooves during scratching in Cu-SO4 and Cu-electroless plating solution at the high loads, and after the scratching copper deposits grew only during immersion in Cu-electroless plating solution. Probe-tip wear was greater in NaOH solution than in distilled water. (C) 2001 The Electrochemical Society.
  • Fabrication of micropores and grooves on aluminum by laser irradiation and electrochemical technique
    T Kikuchi, M Sakairi, H Takahasi, Y Abe, N Katayama
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 148, 11, C740, C745, ELECTROCHEMICAL SOC INC, 2001年11月, [査読有り]
    英語, 研究論文(学術雑誌), Micropores and microgrooves were fabricated on aluminum specimens using anodizing, laser irradiation, and electrochemical techniques. In the fabrication of the micropores, aluminum specimens covered with anodic oxide film were irradiated with a pulsed Nd yttrium aluminum garnet laser (i) on open circuit or (ii) under anodic polarization in NaCl solution. The laser irradiation caused the formation of cone-shaped pores, while the laser irradiation under anodic polarization caused the formation of hemispherical pores. In the fabrication of microgrooves, successive procedures of anodizing, laser irradiation, reanodizing at the laser-irradiated area, and stripping of oxide film were carried out. Microgrooves with a 30 mum linewidth and 20 mum depth were obtained. (C) 2001 The Electrochemical Society.
  • Anodizing of aluminum coated with silicon oxide by a sol-gel method
    K Watanabe, M Sakairi, H Takahashi, K Takahiro, S Nagata, S Hirai
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 148, 11, B473, B481, ELECTROCHEMICAL SOC INC, 2001年11月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum specimens were covered with SiO2 film by a sol-gel coating and then anodized galvanostatically in a neutral borate solution. Time variations in the anode potential during anodizing were monitored, and the structure and dielectric properties of the anodic oxide films were examined by transmission electron microscopy, Rutherford backscattering spectroscopy, and electrochemical impedance measurements. It was found that anodizing of aluminum coated with SiO2 films leads to the formation of anodic oxide films, which consist of an outer Al-Si composite oxide layer and an inner Al2O3 layer, at the interface between the SiO2 film and the metal substrate. The capacitance of anodic oxide films formed on specimens with a SiO2 coating was about 20% larger than without a SiO2 coating. In the film formation mechanism, the conversion of Al2O3 to Al-Si composite oxide at the interface between the inner and outer layers is discussed in terms of inward transport of Si-bearing anions across the outer layer. (C) 2001 The Electrochemical Society.
  • アノード酸化/レーザー照射/Ni-P無電解めっきによるプラスチック射出成形用金型の試作
    坂入 正敏, 文 聖模, 高橋 英明, 嶋村 清隆
    表面技術 = The Journal of the Surface Finishing Society of Japan, 52, 8, 553, 556, 社団法人 表面技術協会, 2001年08月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • アノード酸化・レーザー照射・電気化学的手法によるアルミニウムの表面マイクロテクノロジー
    菊地 竜也, 坂入 正敏, 高橋 英明
    表面技術 = The Journal of the Surface Finishing Society of Japan, 52, 1, 84, 85, 社団法人 表面技術協会, 2001年01月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Confocal scanning laser microscopy of the surface of anodized A15052 alloy
    SM Moon, M Sakairi, H Takahashi
    CORROSION AND CORROSION PROTECTION, 2001, 22, 91, 98, ELECTROCHEMICAL SOCIETY INC, 2001年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), The surface morphology of Al5052 alloy anodized in sulfuric acid solution was investigated using a confocal scanning laser microscope (CSLM). The incident laser beam appeared to be reflected partially by the outer oxide surface, by the defects in the oxide film and/or by the inner oxide/metal interface. This allows us to obtain the CSLM images of the surface, defects in the oxide and the metal/oxide interface, separately, by choosing different scanning ranges of the focused Z position. Two different types of defects in the anodic oxide film were observed on the CSLM images : dark spots and bright spots. The dark and bright spots were attributed to the irregular pore structure or holes in the oxide film left after the preferential dissolution of magnesium and iron-rich region in the oxide film, respectively.
  • Effect of mechanical, chemical, and thermal treatments on the repairing of voids in re-anodizing of aluminum covered with composite oxide films
    H Takahashi, Y Tamura, M Sakairi, H Uchi
    CORROSION AND CORROSION PROTECTION, 2001, 22, 50, 57, ELECTROCHEMICAL SOCIETY INC, 2001年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), Composite oxide films formed on aluminum by boiling in pure water and the subsequent anodizing in a neutral solution include many voids, which are either linked with each other through cracks or isolated from others. Repairing of the voids by re-anodizing at a low constant current density was attempted after mechanical, chemical, and thermal treatments. Chemical treatments affected considerably the potential vs. time curves during re-anodizing, suggesting the linkage of the isolated voids by chemical dissolution of oxide. Thermal treatments affected the curve appreciably and mechanical treatments affected it slightly. Successive procedure of thermal and chemical treatments showed a synergetic effect on the curve, while the opposite procedure showed a slight effect.
  • Anodizing of aluminum covered with SiO2 by sol-gel coating - Formation mechanism of composite oxide films with high potential sustainability
    K Watanabe, M Sakairi, H Takahashi, S Hirai, S Nagata
    CORROSION AND CORROSION PROTECTION, 2001, 22, 146, 153, ELECTROCHEMICAL SOCIETY INC, 2001年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), Aluminum specimens were covered with SiO2 film by a sol-gel coating and then anodized galvanostatically in diluted borate solution. Time-variations in the anode potential during anodizing were monitored, and the structure and dielectric properties of anodic oxide films were examined by TEM-EDX, RBS, and electrochemical impedance measurements.
    It was found that anodizing of aluminum coated with SiO2 films leads to the formation of anodic oxide films, which consist of an outer AI-Si composite oxide layer and an inner Al2O3 layer, at the interface between the SiO2 film and the metal substrate. The breakdown potential of anodic oxide films formed on specimens with SiO2-coating was about 100V larger than without SiO2-coating.
    In the film formation mechanism, the conversion of Al2O3 to Al-Si composite oxide at the interface between the inner and outer layers is discussed in terms of inward transport of Si-bearing anions across the outer layer.
  • Anodizing of Aluminum Covered with SiO2 by Sol-Gel Coating -Formation Mechanism of Composite Oxide Films with High Potential Sustainability-               
    K.Watanabe, M.Sakairi, H.Takahashi, S.Nagata, S.Hirai
    Proceedings of the ECS&ISE Joint International Meeting, 420, 425, 2001年, [査読有り]
    英語
  • Laser-assisted electroless Ni-P deposition at selected areas on Al (-Mg, Si, Cu) alloys
    SZ Chu, M Sakairi, H Takahashi, K Simamura, K Abe
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 147, 6, 2181, 2189, ELECTROCHEMICAL SOC INC, 2000年06月, [査読有り]
    英語, 研究論文(学術雑誌), Local deposition of Ni-P alloys on highly pure aluminum, commercially pure aluminum, Al-Cu-Mn, Al-Mg, and Al-Si-Mg alloys was attempted by anodizing, laser irradiation, and electroless plating. Specimens were first anodized at 15 V in 16% H2SO4, and then irradiated with a pulsed Nd-yttrium-aluminum-garnet laser in a Ni2+/H2PO2- solution. Nickel-phosphorous electroless plating was finally carried out in a Ni2+/H2PO2- solution with 0.6 ppm of Pb2+ ions. The effect of alloying elements on the Ni-P deposition during electroless plating was investigated. Anodic oxide films on all the specimens were sufficiently stable in Ni-P electroless plating solution and able to ensure local deposition of Ni-P only at the laser-irradiated areas. The deposition rate of Ni-P on all the aluminum alloy specimens was higher than that on highly pure aluminum. The effect of the alloying elements on the Ni-P deposition in electroless plating is discussed in terms of the catalytic function in Ni-P electroless deposition and the inhibition of the oxide film Formation during laser irradiation. (C) 2000 The Electrochemical Society. S0013-4651 (99)09-035-7. All rights reserved.
  • アルミニウムアノード酸化皮膜成長のIn-situ AFM観察-皮膜表面の平坦化機構-
    高島 房生, 三輪 浩二, 坂入 正敏, 高橋 英明
    表面技術 = The Journal of the Surface Finishing Society of Japan, 51, 6, 625, 632, 一般社団法人 表面技術協会, 2000年06月, [査読有り]
    日本語, 研究論文(学術雑誌), Two kinds of alminum specimens were prepared: 1) chemically polished specimen (CP-specimen) and 2) surface-roughened specimen (PD-specimen) obtained by removing a porous anodic oxide film through dissolution in an H3PO4/CrO3 solution. The change in the surface roughness of CP- and PD-specimens during anodizing in a neutral solution was monitored with in situ atomic force microscopy (AFM) and transmission electron microscopy (TEM) as a function of anode potential. The change in surface roughness was also simulated mathematically, by assuming the Pilling-Bedworth ratio is constant during film...
  • Copper electroless plating at selected areas on aluminum with pulsed Nd-YAG laser
    SZ Chu, M Sakairi, H Takahashi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 147, 4, 1423, 1434, ELECTROCHEMICAL SOC INC, 2000年04月, [査読有り]
    英語, 研究論文(学術雑誌), Local deposition of copper on aluminum was attempted by the successive processes of anodizing, laser irradiation, and electroless plating. Aluminum specimens covered with anodic oxide films were immersed in Cu2+, Cu2+/H2PO2-, and diluted NaOH solutions, and irradiated with a pulsed yttrium aluminum garnet (YAG) laser. The time variation in the rest potential of the specimens was followed during laser irradiation by a potentiometer, and the change of the surface composition by laser irradiation was examined by X-ray photoelectron spectroscopy(XPS). After the laser irradiation, copper electroless plating was carried out in (Cu2+ Ni2+)H2PO2- solutions with or without Pb2+ or thiourea. The rest potential measurements and XPS analysis suggested that Cu particles nucleate at the film-removed area by laser irradiation in Cu2+ and Cu2+/H2PO2- solutions. A copper layer was obtained at the irradiated area by the subsequent electroless plating, and the copper nuclei acted as catalytic centers at the very initial stage in copper electroless plating. The effects of Pb2+ and thiourea concentration and the deposition temperature on the kinetics of copper deposition is also discussed. (C) 2000 The Electrochemical Society. S0013-4651(99)06-129-7. All rights reserved.
  • アノード酸化を基礎とする新規なアルミニウム表面改質・加工技術 -機能性表面の創成を目指して-
    高橋 英明, 坂入 正敏, Chu 松竹, 渡辺 恵司, 菊地 竜也, 三輪 浩二, 加藤 善大, 上西 早苗
    軽金属, 50, 11, 544, 551, 軽金属学会, 2000年, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Formation of Al-(Zr,Si) Composite Oxide Films on Aluminum by Sol-Gel Coating/Anodizing               
    K.Watanabe, M.Sakairi, H.Takahashi, K.Takahiro, S.Nagata, S.Hirai
    Proc.2nd Inter.Symp.on Aluminum Surf.Sci.and Tech.(ASST2000), 420, 425, 2000年, [査読有り]
    英語
  • Anodizing of aluminum coated with zirconium oxide by a sol-gel process I. Effect of heat treatment on the formation of the anodic oxide film
    K Watanabe, M Sakairi, H Takahashi, K Takahiro, S Nagata, S Hirai
    ELECTROCHEMISTRY, 67, 12, 1243, 1248, ELECTROCHEMICAL SOC JAPAN, 1999年12月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum specimens were covered with zirconium oxide films by sol-gel dip coating at T-h = 573 and 873 K, and then anodized galvanostatically in a neutral berate solution. The time-variation in the anode potential during anodizing was monitored, and the structure of anodic oxide films was examined by TEM, EDX, and RES. During anodizing of specimens coated with ZrO2 at T-h = 573 K, the anode potential, E-a, increased linearly with time, t(a), and the slope of the E-a vs, t(a) curve increased with increasing the number of sol-gel coatings. An anodic oxide film, which was composed of an inner Al2O3 layer and an outer Al-Zr composite oxide layer, grew at the interface between the ZrO2 layer and metal substrate during anodizing. The thickness of the inner layer increased with t(a), whereas the thickness of the outer layer showed a maximum before decreasing with t(a). Specimens coated with ZrO2 at T-h = 873 K showed E-a -jumps between 40 and 110 V just after the commencement of anodizing, and then a slow E-a increase. An anodic oxide film composed of a single layer of Al2O3, formed beneath the ZrO2 layer during anodizing. The mechanism of the formation of anodic oxide films on aluminum coated with ZrO2 films is discussed in terms of ion transport across the anodic oxide film.
  • Formation of Al-Zr composite oxide films on aluminum by sol-gel coating and anodizing
    K Watanabe, M Sakairi, H Takahashi, S Hirai, S Yamaguchi
    JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 473, 1-2, 250, 255, ELSEVIER SCIENCE SA, 1999年09月, [査読有り]
    英語, 研究論文(学術雑誌), Al specimens were covered with zirconium oxide film by sol-gel coating using zirconium alkoxide, and then anodized galvanostatically in a neutral berate solution. The time-variation in anode potential during anodizing was followed, and the structure and dielectric properties of the anodic oxide him were examined by TEM, EDX, RES, and impedance measurements. It was found that the anode potential increases during anodizing, and that the slope of the potential-time curve becomes steeper with increasing number of dippings in sol-gel solution. An anodic oxide film was formed at the interface between zirconium oxide and the aluminum substrate during anodizing. This anodic oxide film was composed of an inner Al2O3 layer and an outer Al-Zr composite oxide layer. The capacitance of anodic oxide films formed after sol-gel Zr-oxide coating and anodizing was about 20% higher than without Zr-oxide coating. (C) 1999 Elsevier Science S.A. All rights reserved.
  • アルミニウムアノード酸化/レーザー照射/電気めっきを用いた微細回路板の作製
    菊地 竜也, 坂入 正敏, 高橋 英明, 阿部 芳彦, 片山 直樹
    表面技術 = The Journal of the Surface Finishing Society of Japan, 50, 9, 829, 835, 一般社団法人 表面技術協会, 1999年09月, [査読有り]
    日本語, 研究論文(学術雑誌), Fine-pattern coils were fabricated on an insulating board using anodizing, laser irradiation, nickel deposition, insulating board sticking, and aluminum substrate dissolution. Aluminum specimens covered with porous anodic oxide films were irradiated by a pulsed Nd-YAG laser through a beam splitter, iris diaphragm, convex lens, and quartz window in a nickel electroplating solution to remove anodic oxide film. During laser irradiation, the specimen was moved 3-dimensionally with an XYZ stage by a personal computer.The width of the trench produced by film removal increased with increasing lase...
  • Nucleation of metals on aluminum by laser irradiation and the effect on Ni-P electroless deposition
    SZ Chu, M Sakairi, Saeki, I, H Takahashi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 146, 8, 2876, 2885, ELECTROCHEMICAL SOC INC, 1999年08月, [査読有り]
    英語, 研究論文(学術雑誌), The mechanism of direct Ni-P electroless deposition on aluminum by pulsed yttrium aluminum garnet (YAG) laser irradiation in Ni2+/H2PO2- solution was investigated by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) with energy-dispersive X-ray (EDX) analysis. Aluminum specimens covered with porous anodic oxide films were irradiated with a pulsed YAG laser in solutions containing Pd2+, Cu2+, Ni2+, or Ni2+/H2PO2- ions, and then localized Ni-P electroless plating was attempted at the laser irradiated area in Ni2+/H2PO2- solution. It was found that laser irradiation in solutions containing Pd2+, Cu2+, or Ni2+ ions causes the deposition of small metallic particles of Pd, Cu, or Ni at the laser-irradiated area on the aluminum surface which was exposed to the solution after removal of anodic oxide film. The deposition of the metals is due to a redox reaction between the aluminum substrate and the Pd2+, Cu2+, or Ni2+ ions. During laser irradiation in Ni2+/H2PO2- solution, Ni-P and Ni were deposited by redox reactions between Ni2+ and H2PO2- as well as between Ni2+ and Al. Palladium and nickel (Ni-P) particles deposited during the laser irradiation acted as catalytic centers for the subsequent Ni-P electroless plating, while Cu particles did not promote the electroless plating. (C) 1999 The Electrochemical Society. S0013-4651(98)11-019-4. All rights reserved.
  • AIのアノード酸化とレーザー照射を利用した金属微細構造の作成 - 新LIGAプロセスを目指して -
    菊地 竜也, Chu 松竹, 加藤 善大, 坂入 正敏, 高橋 英明
    表面技術 = The Journal of the Surface Finishing Society of Japan, 50, 8, 697, 704, 一般社団法人 表面技術協会, 1999年08月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • ゾル・ゲルコーティング-Zr酸化物に覆われたアルミニウムのアノード酸化
    渡辺 恵司, 坂入 正敏, 高橋 英明, 平井 伸治, 山口 貞衛
    表面技術 = The Journal of the Surface Finishing Society of Japan, 50, 4, 359, 366, 一般社団法人 表面技術協会, 1999年04月, [査読有り]
    日本語, 研究論文(学術雑誌), Aluminum specimens were covered with zirconium oxide film by a sol-gel coating and galvanostatically anodized in a neutral borate solution. The time variation in anode potential during anodizing was monitored, and the structure and dielectric properties of the anodic oxide film were studied by TEM, EDX, RBS, and impedance measurement.We found that the anode potential increases with time, and that the slope of the potential-time curve increases with increasing the numbers of sol-gel dip coatings. During anodizing, an anodic oxide film, which consisted of an inner Al2O3 layer and an outer Al-...
  • Local deposition of Ni-P alloy on aluminum by laser irradiation and electroless plating
    SZ Chu, M Sakairi, H Takahashi, ZX Qiu
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 146, 2, 537, 546, ELECTROCHEMICAL SOC INC, 1999年02月, [査読有り]
    英語, 研究論文(学術雑誌), A new technique on local modification of aluminum was attempted by combining anodization, laser irradiation, and electroless plating. Aluminum specimens covered with a porous anodic oxide film were immersed in Ni2+/H2PO2- solution containing Pb2+ ions at C-Pb(2+) = 0-2.4 ppm and irradiated 293 K with a pulsed yttrium aluminum garnet (YAG) laser through a lens and quartz window to remove the oxide film locally. The specimen was then transferred into the Ni2+/H2PO2- solution at 358-368 K to deposit Ni-P alloys on the aluminum by electroless plating. Local deposition of amorphous Ni-P alloys (9.5-11.2 atom % P) at the laser-irradiated area was obtained at C-Pb(2+) = 0.3-2.4 ppm above 358 K. The effects of C-Pb(2+) on the rate of Ni-P electroless deposition as well as on the morphology and crystal structure of Ni-P deposits were also investigated. It was found that the addition of Pb2+ ions to the solution leads to the deposition of Ni-P alloys with a smooth surface and that it slightly affects the composition and crystal structure of the deposits. (C) 1999 The Electrochemical Society. S0013-4651(98)03-102-4. All rights reserved.
  • Effect of benzotriazole on anodizing of 2024 aluminum alloy in sulfuric acid at low temperature
    M Sakairi, P Skeldon, GE Thompson, GC Wood, K Stevens
    PASSIVITY AND LOCALIZED CORROSION, 99, 27, 171, 180, ELECTROCHEMICAL SOCIETY INC, 1999年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), The influence of benzotriazole, at concentrations to 50 kg/m(3), on the efficiency of anodizing of 2024 (T6) alloy and 99.99 wt % Al at a constant current density of 50 A/m(2) in 24.5 wt % H2SO4 solution at 277 K has been investigated by measurement of oxygen gas evolution and examination of ultramicrotormed cross sections of anodic oxide films. The porous film morphology on 2024 (T6) alloy is modified compared with that produced on high purity aluminum, with the branched and relatively tortuous porosity of the films on the alloy contrasting with the linear porosity of the films on high purity aluminum. Large copper-rich second phase particles are oxidized to form soluble species, leaving cavities in the film. Benzotriazole increase the efficiency of film growth on 2024 (T6) alloys. Significant amounts of oxygen gas are generated during anodizing of the alloy, typically equivalent to about 20% loss in current efficiency.
  • Reformation of anodic oxide films on aluminum after destruction with laser irradiation in solutions. Effects of anion and pH
    H Takahashi, M Sakairi, Y Ohira
    PASSIVITY AND LOCALIZED CORROSION, 99, 27, 377, 386, ELECTROCHEMICAL SOCIETY INC, 1999年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), Aluminum specimens covered with anodic oxide films were immersed in i) a neutral berate solution, ii) berate solutions containing Cl- ions, iii) NaCl solutions, and iv) phosphate solutions with different pH, and irradiated with one pulse of Nd-YAG laser at constant set potential, Es. Current transients (i vs. t) after laser irradiation were monitored by a PC system with AD converter.
    In the borate solution, the formation and dissolution of oxide films started at 0.4 ms after laser irradiation, and were followed by an exclusive oxide film formation after t = 10 ms, showing a slope of -1 in log i vs. log t curves. The ratio of the film dissolution rate to the film formation rate at the initial stage was higher at higher E-s.
    In NaCl and NaCl / berate solutions, current transients were similar to that in the berate solution at E-s = -1 V (vs. Ag/AgCl), while above E-s = -0.5 V, i increased again after showing a minimum, i(m), at t(m). With increasing Cl concentration, i(m) increased, and t(m) decreased. The metal substrate dissolved preferentially at the laser-irradiated area above E-s = -0.5 V and this was accompanied by gas evolution.
    Phosphate solutions showed current transients similar to that in the borate solution at each pH and E-s, and the slope of log i vs. log t curves became steeper with t to exceed -1 at t = 10 ms. The initial peak current showed a minimum at pH = 2 - 3, suggesting the formation of aluminum and phosphate complexes.
  • レーザー照射および局部Niめっきによるアルミニウム表面のパターニング II. レーザー照射部における局部Niめっきと微細パターン作製
    坂入 正敏, 若林 潤, 高橋 英明, 阿部 芳彦, 片山 直樹
    表面技術 = The Journal of the Surface Finishing Society of Japan, 49, 11, 1227, 1232, 一般社団法人 表面技術協会, 1998年11月, [査読有り]
    日本語, 研究論文(学術雑誌), Fabrication of fine pattern on an aluminum surface with pulsed YAG laser irradiation and subsequent nickel plating has been reported in two consecutive papers. The second paper studies nickel deposition on aluminum irradiated with a pulsed YAG laser, and pattern fabrication with nickel deposition.Aluminum specimens covered with porous anodic oxide film were irradiated with a pulsed YAG laser in air and in Ni2+ ion solutions using a three dimensional stage controlled by computer, and then nickel was electrodeposited and studied potentiostatically as functions of cathode potential, Ec, Ni2+ i...
  • レーザー照射および局部Niめっきによるアルミニウム表面のパターニング I. レーザー照射によるアノード酸化皮膜の破壊挙動
    坂入 正敏, 若林 潤, 高橋 英明, 阿部 芳彦, 片山 直樹
    表面技術 = The Journal of the Surface Finishing Society of Japan, 49, 11, 1220, 1226, 一般社団法人 表面技術協会, 1998年11月, [査読有り]
    日本語, 研究論文(学術雑誌), Fabrication of fine pattern on an aluminum surface with pulsed YAG laser irradiation and subsequent nickel plating has been reported in two consecutive papers. The first paper studies anodic oxide film removal from aluminum by laser irradiation.Aluminum specimens covered with porous anodic oxide films were irradiated with one YAG laser pulse in air and in Ni2+ ion solutions to examine the effect of laser power, P, defocusing distance, Δx, and irradiation atmosphere on the size of film removed area.Anodic oxide films were thoroughly removed by laser irradiation at P>2mW in both air and a sol...
  • Reformation of anodic oxide films on aluminum after destruction by pulsed Nd-YAG laser irradiation
    M Sakairi, Y Ohira, H Takahashi
    PROCEEDINGS OF THE SYMPOSIUM ON PASSIVITY AND ITS BREAKDOWN, 97, 26, 643, 653, ELECTROCHEMICAL SOCIETY INC, 1998年, [査読有り]
    英語, 研究論文(国際会議プロシーディングス), Pulsed Nd - YAG laser was used to investigate the destruction and reformation of barrier type anodic oxide films on aluminum in a neutral berate solution under anodic polarization. Current transients after laser irradiation were measured by personal computer with A/ D conversion system, to examine the effect of laser power, film formation potential, and applied potential on the current transient. By laser irradiation, the current increased instantaneously and then decreased exponentially with time, suggesting the inverse logarithmic growth rate low in the film formation after destruction by laser. The amount of charge obtained by integrating current transient curves between 0 and 600 ms Linearly increased with increasing applied potential, and this suggests that the thickness of film formed at laser irradiated area is proportional to the applied potential. Current fluctuation was observed at the initial period of film formation for specimens covered with thick oxide films. The current fluctuation is discussed in terms of the specimen vibration due to the film destruction.
  • Formation of Al/(Ti, Nb, Ta)-composite oxide films on aluminum by pore filling
    M Shikanai, M Sakairi, H Takahashi, M Seo, K Takahiro, S Nagata, S Yamaguchi
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 144, 8, 2756, 2766, ELECTROCHEMICAL SOC INC, 1997年08月, [査読有り]
    英語, 研究論文(学術雑誌), Aluminum specimens coated with porous anodic oxide films were dipped in solutions containing Ti4+, Nb5+ or Ta5+ ions and heated in air mainly at 400 degrees C to deposit Ti, Nb, or Ta oxide on the inner walls of pores. After 0 to 7 cycles of the dipping and heating process, the specimens were reanodized in a neutral berate solution to fill the pores with Al2O3. The incorporation of Ti, Nb, or Ta oxide in the anodic oxide films was examined by transmission electron microscopy, Rutherford backscattering spectroscopy, and impedance measurements. Incorporation of Ti, Nb, or Ta oxide was found only in the outermost part of the anodic oxide film after reanodizing up to 400 V. The Al/Ti composite oxide films consisted of an outer Al/Ti-composite oxide layer, an intermediate crystalline alumina layer, and an inner amorphous alumina layer, while the Al/Nb -and Al/Ta-composite oxide films consisted of an outer composite oxide layer and an inner amorphous alumina layer. The parallel electric capacitance of Al/Ti-composite oxide film was 40% higher than those of the other two due to its small thickness and high dielectric constant. The formation mechanisms of the composite oxide films during reanodizing are discussed in terms of the ion transport across the oxide film.
  • Noise reduction .1. For electrochemical measurement system
    M Sakairi, H Takahashi
    DENKI KAGAKU, 65, 5, 359, 364, ELECTROCHEMICAL SOC JAPAN, 1997年05月, [査読有り]
    日本語, 研究論文(学術雑誌)
  • Formation and breakdown of anodic oxide films on aluminum in boric acid borate solutions
    Y Li, H Shimada, M Sakairi, K Shigyo, H Takahashi, M Seo
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 144, 3, 866, 876, ELECTROCHEMICAL SOC INC, 1997年03月, [査読有り]
    英語, 研究論文(学術雑誌), Highly pure aluminum was anodized at a constant current density of 25 A m(-2) at 293 K in 0.5 M boric acid/0, 0.005, or 0.05 M sodium tetraborate solutions; to examine the effect of sodium tetraborate concentration on the formation and breakdown characteristics of barrier oxide films by using inductively coupled plasma atomic emission spectrometry, electroluminescence/photoluminescence measurements, scanning electron microscopy, transmission electron microscopy, and electrochemical impedance spectroscopy. In boric acid/borate solutions, a crystalline alumina formed locally in the middle of the amorphous oxide film. Above the crystalline alumina, a void is formed and may lead to a breakdown of the oxide film at 420 to 540 V. In boric acid solution. an amorphous oxide film grew until 1180 V with the formation and development of imperfections and with enhancement of electroluminescence and gas evolution. At imperfections, the oxide/solution interface was convex and the oxide/metal interface curved in the opposite direction. This deformation is attributed to high-pressure O-2 evolved in the pores of imperfections and to the local formation and dissolution of oxide. The breakdown of the oxide film started when the O-2 evolution and oxide dissolution at imperfections become predominant. The mechanism of formation and breakdown of the anodic film in the boric acid/borate solutions is discussed in terms of pH buffering of the anodizing solution, and the electronic structure of anodic oxide films is correlated with electroluminescence and photoluminescence spectrum results.
  • ステンレス鋼の孔食萠芽に及ぼす硫化物の影響
    坂入正敏, 西方 篤, 水流 徹
    Zairyo-to-Kankyo, 40, 3, 183, 187, 1991年, [査読有り]
    英語, 研究論文(学術雑誌), Stochastic properties of current fluctuations observed before a stable pit propagation were analyzed in a buffer neutral NaCl solution. Distribution and size of sulfides in a 304 stainless steel were changed by surface remelting and rapid soldification by CO2 laser and following heat treatments. Increase in the concentration of sulfides slightly increase the frequency in occurence of pit embryos, and increase of the size of sulfide decreased it. The volume, life time, peak height and stochastic nature of pit embryos, however, were not affected drastically by the size and distribution of sulfides. Weibull plots of life time revealed that there is a critical size for pit embryo formation. © 1991, Japan Society of Corrosion Engineering. All rights reserved.
  • 孔食萠芽の生存時間に与える電位と塩化物イオン濃度の影響
    坂入正敏, 水流 徹
    表面技術, 41, 9, 940, 941, The Surface Finishing Society of Japan, 1990年09月, [査読有り]
    英語, 研究論文(学術雑誌)
  • Statistical analysis of current fluctuations during pit embryos formation on stainless steel               
    Tooru Tsuru, Masatoshi Sakairi
    Corrosion engineering, 39, 7, 401, 409, 1990年
    英語, 研究論文(学術雑誌), Current fluctuations in stainless steel under anodic polarization in sodium chloride solutions were measured and analyzed statistically. The frequency of the fluctuations decreased with time after polarization, and the probability of fluctuation was predicted by an exponential function that suggested that the events were independent of each other. The rate of pit embryo formation decreased with increasing polarization potential. The rate of passivation (death probability of embryos), the mean life span, and the peak peak current of the fluctuations did not clearly depend upon the polarization potential and chloride concentration.
  • Spectrum analysis of current fluctuations upon pit generation               
    Tooru Tsuru, Masatoshi Sakairi
    Corrosion engineering, 39, 8, 447, 454, 1990年
    英語, 研究論文(学術雑誌), Simulations of current fluctuations observed during anodic polarization below the pitting potential have been conducted assuming several different shapes of current spikes. The power spectra calculated by the FFT method were characterized by three important values: the power at the lowest frequency, Go(f)
    the break-point frequency on the spectrum, fo
    and the slope, m. It was revealed that the Go(f) corresponded to the energy of the spikes, and depended upon their number of pit (rate of pit embryo formation), their maximum amplitude, and their life span. The slope, m, was determined by the shape of each spike, such as m = 1 for rectangular and saw-toothed spikes and m = 2 for triangular spikes. The break-point frequency, fo, which depended slightly upon the life span and the number of spikes, was considered as an index of the length of time in which relatively many spikes observed.
  • ステンレス綱の孔食萌芽発生に伴う電流振動とその統計的性質
    水流 徹, 坂入正敏
    防食技術, 39, 7, 355, 360, 1990年, [査読有り]
    日本語, 研究論文(学術雑誌), Current fluctuations of a stainless steel under anodic polarization in sodium chloride solutions were measured and analyzed statistically. The frequencies of the fluctuations decreased with time after the polarization and the probability of the fluctuation was predicted by an exponential function which suggested that all the events were independent of each other. The rate of pit embryo formation decreased with increasing polarization potential. The rate of passivation, mean life time and peak current of the fluctuations did not clearly depend on the polarization potential and concentration of chloride.
  • 孔食における電流振動の周波数解析−シミュレ−ションとパワ−スペクトルについて−
    水流 徹, 坂入正敏
    防食技術, 39, 8, 403, 408, 1990年, [査読有り]
    日本語, 研究論文(学術雑誌), Simulations on current fluctuations observed during anodic polarization below the pitting potential have been made assuming several different shapes of current spikes. The power spectra calculated by FFT method were characterized by the power at the lowest frequency G0(f), the break-point frequency on the spectrum f0, and the slope m. It was revealed that the power G0(f) corresponded to the energy of the spikes, so it depended upon the number of spikes (rate of pit embryo formation), their maximum amplitude and the life times. The slope m was determined by the shape of each spike, such as m = 1 for rectangular and saw tooth shape spikes and m = 2 for triangles. The break-point frequency f0 which depended slightly upon the life time and the number of spikes was considered as an index of the duration in which relatively many spikes were observed.
  • THE BREAKDOWN AND REPASSIVATION OF PASSIVE FILMS ON IRON WHISKER AND AMORPHOUS-ALLOYS
    T TSURU, M SAKAIRI
    CORROSION SCIENCE, 31, 361, 366, PERGAMON-ELSEVIER SCIENCE LTD, 1990年, [査読有り]
    英語, 研究論文(学術雑誌)

その他活動・業績

書籍等出版物

  • 2020版・薄膜作製応用ハンドブック,權田俊一監修               
    坂入正敏, 第2編第1章第1節 金属基板
    株)エヌ・ティー・エス, 2020年, [共著]
  • lectrochemistry for Corrosion Fundamentals               
    坂入 正敏, Chapter 5 Hydrogen embrittlement and hydrogen absorption-
    Springer Nature Singapore Pte Ltd., 2018年01月, [共著]
  • 電気化学便覧               
    電気化学会, 5.15ノイズ対策
    丸善, 2012年12月, [分担執筆]
  • Lasers - applications in science and industry               
    Krzysztof Jakubcza, Chapter 9 Application of pulsed laser fabrication in localized corrosion research
    InTec, 2011年, [分担執筆]
  • キャパシタ便覧               
    8.1.1 複合酸化物皮膜の形成によるアルミニウム電解コンデンサーの大容量化
    丸善, 2009年, [分担執筆]
  • Progress in corrosion research               
    Emilio L. Bettini, Re-passivation and initial stage of localized corrosion of metals by using photon rupture technique and electrochemistry
    Nova Science Publishers Inc., 2007年, [分担執筆]
  • Passivitiy of metals and semiconductors, and properties of thin oxide layers               
    P. Marcus, V. Maurice, Formation of Al-Si composite oxide films on aluminum by electrophoretic sol-gel coating/anodizing
    Elsevier B.V, 2006年, [分担執筆]
  • Passivitiy of metals and semiconductors, and properties of thin oxide layers,               
    P. Marcus, V. Maurice, Passivitiy of metals and semiconductors, and properties of thin oxide layers, Initial stage of localized corrosion in artificial pit formed on zinc coated steels by photon rupture
    Elsevier B.V., 2006年, [分担執筆]
  • 水の分析 第5版、日本分析化学会北海道支部編               
    化学同人, 2005年
  • 21世紀版・薄膜作製応用ハンドブック               
    權田俊一監修, 第2編第1章第1節 金属基板
    株)エヌ・ティー・エス, 2003年, [分担執筆]

講演・口頭発表等

  • 低温環境における金属材料の腐食と電気化学計測               
    坂入正敏
    日本金属学会春期講演大会, 2023年03月09日, 日本語, 口頭発表(基調)
    [招待講演]
  • Influence of metal cation on corrosion of metals in aqueous environments               
    M. Sakairi
    6th INTERNATIONAL CONFERENCE ON COMPUTER, COMMUNICATION, CHEMICAL, MATERIALS AND ELECTRONIC ENGINEERING (IC4ME2-2021), 2021年12月26日, 英語, 口頭発表(招待・特別)
    [招待講演], [国際会議]
  • 腐食劣化解析に基づく鋼構造物の最適な維持を目指して               
    坂入正敏
    スクベース設備管理第180委員会第2回研究会, 2020年12月22日, 日本語, その他
    [招待講演]
  • 3Dプリンタにより作製したマルチチャンネル液滴セルによる局部陽極酸化               
    坂入正敏, M. Bilal
    第105回ARS例会(SURTECH), 2020年01月31日, 日本語, 公開講演,セミナー,チュートリアル,講習,講義等
    [招待講演]
  • 鉄鋼材料を長く,安全に使用するための研究               
    坂入正敏
    日本鉄鋼協会,最先端鉄鋼セミナー, 2018年08月30日, 日本語, 公開講演,セミナー,チュートリアル,講習,講義等
    [招待講演]
  • 微小電気化学セルを用いる局部陽極酸化               
    坂入正敏
    第98回ARS例会(SURTECH), 2018年02月16日, 日本語, 公開講演,セミナー,チュートリアル,講習,講義等
    [招待講演]
  • Effect of Anodizing Conditions on Porous Alumina Formation at Selected area with Solution Flow type Micro-Droplet Cell               
    坂入正敏, 松本敏幸
    The International Symposium on Surface Treatment & Modification Technosogies (STMT2017), 2017年11月23日, 英語, 口頭発表(招待・特別)
    [招待講演], [国際会議]
  • Application of solution flow type micro-droplet cell to form shape controlled porous alumina               
    坂入 正敏, 松本 敏幸
    The 3rd Koria-Japan Joint Symposium for ARS & ESS, 2016年11月26日, 英語, 口頭発表(招待・特別)
    [招待講演], [国際会議]
  • XPSと電気化学的手法を用いるいる金属の不働態皮膜構造の解析               
    坂入 正敏, 大谷 恭平
    日本分析化学会第65年会 X線分析研究懇談会, 2016年09月16日, 日本語, 口頭発表(招待・特別)
    [国内会議]
  • Resent research progress in creation of hydrogen-passive surfaces on steels to prevent of hydrogen embrittlement               
    坂入 正敏
    Asian Steel 2015, 2015年10月08日, 英語, 口頭発表(招待・特別)
    [国際会議]
  • 表面処理鋼板の腐食解析(水素脆性を中心に)               
    坂入 正敏
    日本鉄鋼協会 第223回・第224回西山記念技術講座, 2015年10月, 日本語, 公開講演,セミナー,チュートリアル,講習,講義等
    [招待講演], [国内会議]
  • 微小電気化学を用いる腐食と表面処理               
    坂入 正敏
    2015電気化学会秋季大会, 2015年09月12日, 日本語, 口頭発表(招待・特別)
    [国内会議]
  • 大気腐食反応に伴う水素発生・侵入の電気化学的検出と界面反応機構               
    坂入 正敏, 五十嵐洸哉, 高木翔悟
    日本金属学会2015年春期講演大会, 2015年03月20日, 日本語, 口頭発表(基調)
    [国内会議]
  • Evaluation of metal cation effects on galvanic corrosion of aluminum alloys in low chloride ion containing solutions with electrochemical noise               
    坂入 正敏
    ICONS2014, 2014年02月04日, 英語, 口頭発表(招待・特別)
    [国際会議]
  • 溶液フロー型液滴セルを用いる局部表面処理               
    坂入 正敏
    第126回表面技術協会講演大会, 2012年09月27日, 日本語, 口頭発表(招待・特別)
    [国内会議]
  • Corrosion behavior of 11 mass% Cr F/M steel and 15 mass% Cr ODS steel in corrosive solutions               
    M. Sakairi, S. Nigshen, K. Suzuki, S. Ukai
    NIMS Confarence 2012, 2012年06月05日, 英語, 口頭発表(招待・特別)
    [招待講演], [国際会議]
  • Simultaneous hydrogen and rest potential measurement during wet/dry corrosion at scratch on zinc coated steel               
    M. Sakairi, S. Takagi
    材料と環境2012国際セッション, 2012年04月25日, 英語, 口頭発表(招待・特別)
    [招待講演], [国内会議]
  • 超薄切片法によるアノード酸化皮膜の微細構造               
    坂入 正敏
    (社)表面技術協会,第109回講演大会, 2004年03月, 日本語, 口頭発表(招待・特別)
    [招待講演], [国内会議]
  • レーザー皮膜除去法による局部皮膜補修機構と局部表面処理               
    坂入 正敏
    (社)日本金属学会 2000年(第127回)秋期大会, 2000年09月, 日本語, 口頭発表(招待・特別)
    [招待講演], [国内会議]

共同研究・競争的資金等の研究課題

  • トラップ水素をその場定量できる電気化学水素侵入透過測定法の開発と水素脆化解析
    科学研究費助成事業
    2022年04月01日 - 2025年03月31日
    伏見 公志, 坂入 正敏, 宮本 浩一郎
    日本学術振興会, 基盤研究(B), 北海道大学, 22H01822
  • 超弾性NiTi合金への陽極酸化によるTiO2皮膜形成―機序の解明と表面機能の評価
    科学研究費助成事業
    2021年04月01日 - 2024年03月31日
    大津 直史, 太田 信, 坂入 正敏
    日本学術振興会, 基盤研究(B), 北見工業大学, 21H01631
  • 金属カチオンによる不働態皮膜補修機序に基づく耐食性表面の創製
    科学研究費助成事業 基盤研究(B)
    2021年04月 - 2024年03月
    坂入 正敏, 大谷 恭平, 五十嵐 誉廣
    日本学術振興会, 基盤研究(B), 北海道大学, 21H01660
  • 異種金属繰返し多層めっきによる高強度1次元ナノ構造バルク材の作製と物性理解
    科学研究費助成事業
    2011年 - 2013年
    三浦 誠司, 坂入 正敏
    本研究は、従来手法ではサイズや試料強度の上限や微細化の下限に阻まれるナノ構造バルク材の新たな作製法の展開を目指し、微細構造を積み上げるボトムアップ型プロセスとしての「めっき」を利用したプロセスの検討を行い、転位運動の抑制が期待できる層状構造、すなわち1次元的変調構造の作製手法として確立した。開発した「自動ナノ厚さ多層めっきバルク作製装置」では100層を越える多層めっき作製が安定的に作製でき、透過型電子顕微鏡観察、SEM-EBSD観察、ラザフォード後方散乱分光法などによって、積層したCuとNiが同一の方位を有する整合積層領域が多数存在すること、多数の粒界が拡散を促進することなどを明らかとした。
    日本学術振興会, 挑戦的萌芽研究, 北海道大学, 23656443
  • 核燃料再処理環境における金属材料の腐食と環境割れ
    科学研究費助成事業
    2011年 - 2012年
    坂入 正敏, NINGSHEN Sublim, NINGSHEN Sublime
    ステンレス鋼やチタン合金は、耐食性が高いため化学プラントから生体材料等の幅広い環境中で使用されている。しかし,環境が変化すると予想しない腐食が発生することがあり、その腐食挙動は十分に理解されているとは言い難い。特に,次世代高強度材料として期待されている,酸化物分散強化型(ODS)フェライトス鋼については,腐食挙動に関する知見が殆ど無い。
    そこで、本年度はクロム濃度を変えて作製したODSフェライト鋼,オーステナイトステンレス鋼,チタン合金の硝酸環境中を中心に腐食挙動の調査を電気化学的手法と浸漬腐食試験により行うとともに,表面酸化物皮膜構造をXPSにより分析した。
    12%-15%CrODS鋼の3Mから9Mの沸騰硝酸中の腐食挙動を浸漬試験により調査した。浸漬時間は,最長240時間とした。その結果,15%Cr ODS鋼の腐食速度は,0.02-0.24mm/年であり,304Lステンレス鋼の腐食速度は,0.02-016mm/年(浸漬初期)であった。ODS鋼は,240時間浸漬しても粒界腐食は観察されなかった。動電位分極曲線から求めた,腐食電位は硝酸濃度が高くなるに従って,貴側に変化した。XPSによる表面分析の結果から,ODS鋼とステンレス鋼の腐食挙動の違いは,不働態皮膜組成の違いによることを明らかにした。
    JIS-2Tiとチタン合金,(Ti-0.4Ni-0.15Cr-0.01Pd-0.03Ru-Ta, KS50AKOT)の沸騰濃硝酸溶液中における腐食挙動を調査した。浸漬腐食時間は240時間とし,48時間毎に溶液を交換した。腐食速度は,JIS-2Tiで0.07mm/年,チタン合金で0.000763mm/年であった。
    ODS鋼の硝酸環境中における使用の可能性を明らかにした。
    日本学術振興会, 特別研究員奨励費, 北海道大学, 11F01069
  • バルブ金属のアノード酸化を基礎とするマイクロ・ナノ構造構築技術のフロンティア
    科学研究費助成事業
    2007年 - 2008年
    坂入 正敏, 高橋 英明, 菊地 竜也, 高橋 英明, 坂入 正敏
    本研究においては、電気化学的手法とレーザー照射を用いることにより、アルミニウムを中心とするバルブ金属表面にマイクロ・ナノ構造を構築し、新規な性質を付与する技術の開発を目的とした。高容量電解コンデンサーの試作、マイクロ・ナノ電子デバイスの作製および導電性高分子・無電解めっきを応用した新規表面処理法の開発を実現し、バルブ金属をエレクトロニクス・ナノテクノロジーの分野において利用するための新たな活用法を開拓することに成功した。
    日本学術振興会, 基盤研究(A), 北海道大学, 19206078
  • レーザー照射/電気化学複合プロセスによる三次元マイクロアクチュエーターの試作
    科学研究費助成事業
    2004年 - 2005年
    高橋 英明, 坂入 正敏
    アルミニウムのアノード酸化・レーザー照射・電着塗装・導電性高分子析出の連続プロセスにより、アクリル樹脂/金/導電性ポリピロールの3層からなるマイクロアクチュエーターを試作した。このアクチュエーターを各種カチオンを含む水溶液中に浸漬し、アクチュエーターの動作挙動を観察したところ、1価および2価のカチオンを含む溶液においては、ポリピロールの膨張・収縮による試料の動作が観察されたが、3価のカチオンを含む溶液の場合には、試料は動作しなかった。また、カチオンの価数が大きくなると、アクチュエーターの移動距離が小さくなることがわかった。これは、カチオンの価数が大きくなると、ポリピロール膜中に取り込まれる水和カチオンの量が少なくなるためである。
    これまでの研究成果を元に、三次元形状を有するアルミニウム試料を用いて、上述の連続プロセスにより三次元マイクロマニピュレーターを試作した。このマニピュレーターは、コイル状の微細構造体先端に4本の可動部を有する。試作したマイクロマニピュレーターをドデシルベンゼンスルホン酸ナトリウム水溶液中に浸漬したのち、あらかじめ水溶液中に浸漬したシリンダー状のセラミックス構造体をターゲットとしてマニピュレーターの性能を評価した。マニピュレーターの電位を-0.8Vから0V(銀塩化銀参照電極基準)に変化すると、4本の可動部がセラミックスを保持し、その後のマニピュレーターの移動により、セラミックス試料を移動させることができた。すなわち、このマイクロマニピュレーターを用いることにより、極めて微細なターゲット材料を任意の位置に移動できる。このような三次元マイクロマニピュレーターの実現は、世界でも初めての研究成果であり、今後の研究により、マイクロマシン分野や医療分野などに応用できるものと考えられる。
    日本学術振興会, 萌芽研究, 北海道大学, 16656221
  • 高輝度光微細加工による生体内物質分析用微小電気化学反応セル創製に関する研究
    科学研究費助成事業
    2003年 - 2004年
    坂入 正敏, 石田 晃彦
    本研究課題は、高輝度光(集光したパルスYAGレーザー照射)表面微細加工法と電気化学的手法により、酵素反応によって生体内で生成される過酸化水素などの、生体微量物質分析用微小電気化学セルをアルミニウム上に作製すること、さらに、対極などを取り付け微小電気化学分析システムにして、その性能を評価することを目的としている。
    昨年度は、アルミニウムを用いてアノード酸化、レーザー加工、電気めっきを用いて、2電極型システムを作製でき、K_3Fe(CN)_6/K_4Fe(CN)_6の混合溶液(約1.5μl)を用いてCV測定を行ったところ、アノードピーク電流の走査速度依存性や濃度依存性を確認できたが、ピーク形状および液漏れの問題があった。そこで、本年度は、流路などの形状の改良および作製工程の改良を行い、より完成度の高い生体微量物質分析用微小電気化学セルの作製およびその電気化学的特性評価を行った。
    微細溝および微細貫通孔には、レーザー照射後、再度アノード酸化することで、保護性の皮膜を形成し、電極部にはめっきにより金を析出させた。これら、再アノード酸化および金めっきにより、各種溶液で安定に動作可能な、理論内容量1.5μlの微小電気化学セルを作製できた。作製したセルを用いて、電気化学測定を行った結果、従来のマクロ電極と同様のサイクリックボルタモグラムが測定できた。すなわち、アノードピーク電流は電位走査速度の平方根に比例して増加し、その傾きから電極面積を見積もった結果、妥当な値を得ることができた。
    日本学術振興会, 萌芽研究, 北海道大学, 15656177
  • Local Electrochemistry by Solution Flow Type Micro-droplet Cell               
    2003年
    Localized electrochemical reaction studied by micr-droplet cell
    競争的資金
  • レーザー照射/有機膜泳動電着による微細パターニングに関する研究
    科学研究費助成事業
    2001年 - 2002年
    高橋 英明, 坂入 正敏
    円筒状アルミニウム試料(直径2mm)をアノード酸化し、表面に多孔質酸化皮膜を形成したのち、これを蒸留水中に浸漬し、回転・上下動をさせながらパルスNd-YAGレーザーを照射してアノード酸化皮膜を局部的に破壊・除去した。レーザー照射試料をアクリル酸オリゴマーの溶液中に浸漬し、アノード分極することにより、アクリル樹脂が皮膜除去部のみに析出させた。その後、加熱処理により、脱水とアクリル樹脂の重合を促進した。
    アクリル樹脂表面の親油性とアノード酸化皮膜表面の親水性とを利用し、微細円筒プリント原板としての可能性を調べた。すなわち、油性塗料をアクリル樹脂上に塗布し、紙の上を回転させることにより、円筒プリント原板上に描いたパターンを紙に転写させることを試みた結果、数十ミクロンの線幅のパターンを、うまく転写できることを見出した。
    アクリル樹脂析出試料をNaOH溶液中に浸漬し、素地金属および酸化皮膜を溶解除去することにより、アクリル樹脂からなる円筒状かごを形成することに成功した。このかご状構造体は、細線を網目状に編んであるものではなく、一体構造であることが特徴である。すなわち、このアノード酸化/レーザー照射/泳動電着塗装の連続プロセスは、三次元微細有機構造体の新規作成法として注目される。
    日本学術振興会, 萌芽研究, 北海道大学, 13875134
  • フォトンラプチャー法による局部皮膜再生機構の研究
    科学研究費助成事業
    2000年 - 2001年
    坂入 正敏
    本研究は、フォトンラプチャー法により、アノード酸化皮膜に覆われたアルミニウムおよびその合金の各種水溶液中の微小かつ瞬間的な皮膜の修復現象を解明しようとするものである。
    本年度は、昨年度の結果を基に、アノード酸化したアルミニウム合金めっき層を各種溶液中においてフォトンラプチャー法により皮膜を破壊した後、定電位における電流の時間の時間変化を測定し皮膜の再生挙動を調査した。
    1)アノード酸化した試料断面を透過型電子顕微鏡で観察した結果、試料表面に緻密なアノード酸化皮膜が形成しており、その厚さはほぼ純アルミニウムのそれと同様であった。熱水処理することで、皮膜の保護性が向上することが明らかになった。
    2)塩化物イオンを含まないpH9.2のホウ酸溶液中において、定電位で電流の時間変化を測定した結果、皮膜破壊後電流は急激に増加し、0.3ms付近で最大値をとった後、指数関数的(傾き-1)に減少した。つまり、合金めっき層においても、従来の純アルミニウムの結果と同様に、皮膜の再生が逆対数則に従っているものと考えられた。
    また、皮膜再生中に流れる電気量は、設定電位に比例して大きくなり、局部的に再生する皮膜の厚さが電位に比例して厚くなっていくことも明らかになった。
    3)塩化物を含む溶液中において、電流は0.3ms付近で極大値をとった後、指数関数的には減少しなかった。高電位と高濃度においては、時間の経過とともに増加した。つまり、皮膜の補修が起こらず、局部的な金属の溶解が起こった。分極後、試料表面を共焦点走査型レーザー顕微鏡観察した結果、レーザー照射部に腐食生成物が観察された。
    日本学術振興会, 奨励研究(A), 北海道大学, 12750631
  • 新規なアルミニウム表面技術の開発に関する研究
    科学研究費助成事業
    1999年 - 2001年
    高橋 英明, 坂入 正敏, 清水 健一
    本研究は、国際共同研究であり、「アルミニウム表面処理に関する新技術開発」のため、日本とベルギーとの間でおこなったものである。日本側から高橋英明、坂入正敏(北海道大学)および清水健一(慶応義塾大学)が参加し、ベルギー側からH.terrynおよびJ.Vereecken(Frije Universiteit, Brussels)が参加した。北海道大学では、レーザー照射、AFMプローブ加工などによるマイクロ・ナノパターンの形成および複合酸化物皮膜形成による新規電解コンデンサーの開発の研究を進め、慶応大学では、アルミニウム合金のアノード酸化皮膜の構造の精密解析と制御に関する研究を行った。また、ベルギーにおいては、アルミニウムの化成処理、ACエッチング、ACアノード酸化、アノード酸化のさいの熱移動に関する研究を進めた。これらの研究を進める上で相互に意見交換を行うとともに、アドバイス・アイディアに基づいて更なる研究の進展を測った。また、アノード酸化皮膜構造の精密計測に関して相互に助け合い、新しい測定手法の開発などにつながった。
    研究費のほとんどは、相互に研究室を訪問し、討論・測定などを通じて知識および情報の交換を行うのに用いられた。訪問の記録は、以下の通りである。
    H.11:高橋英明、坂入正敏、清水健一が、ベルギーを訪問。 Prof.Terrynが札幌、大阪、東京を訪問。
    H.12:坂入正敏がベルギーを訪問。Prof.Vereeckenが札幌、東京を訪問。
    H.13:坂入正敏、清水健一がベルギーを訪問。Prof.Terrynが札幌、東京を訪問。
    国際交流の成果は、充分に挙がり、今後のアルミニウム表面技術の研究の進展に大きな足跡を残したと考えられる。
    日本学術振興会, 基盤研究(B), 北海道大学, 11694112
  • レーザー照射/AFM加工/電気化学を用いる微細電子・機械デバイスの作製技術の開発
    科学研究費助成事業
    1999年 - 2001年
    高橋 英明, 坂入 正敏, 相馬 道明
    本研究は、アルミニウムのアノード酸化技術を基に、これにレーザー照射技術、AFMプローブ加工技術および電気化学的手法を組み合わせ、マイクロ機械・電子デバイスの作製技術の発展を目的にしたものであり、平成11年度〜平成13年度にわたって行われたものである。
    1)アノード酸化・レーザー照射・無電解NiPめっきによるプラスチック射出成型用金型の作成
    アノード酸化皮膜化成アルミニウムを金属イオンを含む溶液中に浸漬し、これにパルスYAGレーザーを照射することにより、皮膜を局部的に破壊・除去する。その後、無電解めっきにより、皮膜除去部のみにNiPを析出させる。この方法により生分解プラスチック製ペグを作製するアルミニウム製金型を作製することができた。
    2)レーザー照射・電気化学エッチングによる微細ピットおよび微細溝の作製
    アノード酸化皮膜化成アルミニウムをNaCl溶液中に浸漬し、アノード分極下でパルスYAGレーザーを照射することにより、半円球状のマイクロピットを形成することができた。また、アノード酸化・レーザー照射・再アノード酸化・酸化皮膜溶解の連続プロセスにより幅数十ミクロンの溝をアルミニウム表面上に形成することに成功した。
    3)AFMプローブ加工によるナノスケール溝の形成
    薄いアノード酸化皮膜に覆われたアルミニウムを各種の水溶液中に浸漬し、原子間力顕微鏡のプローブで表面をスクラッチすることにより、数百ナノメートル幅の極微細溝を形成することに成功した。また、この加工速度は、溶液のpHおよび化学組成いにより大きく変化することを見出した。
    4)アノード酸化・レーザー照射・電気めっきによる微細Niワイヤーの作製
    アノード酸化皮膜化成した直径2〜5mmのアルミニウム棒をNi2+溶液中に浸漬し、試料を一定速度で回転・上昇させながらレーザーを照射した。その後、カソード分極によりレーザー照射部にNiを析出させ、素地金属をNaOH溶液中で溶解することにより、幅50ミクロンのスプリング状のワイヤーを」形成することができた。
    日本学術振興会, 基盤研究(A), 北海道大学, 11355029
  • アノード酸化を利用する多元系アルミニウム複合酸化物皮膜の形成
    科学研究費助成事業
    1999年 - 1999年
    高橋 英明, 坂入 正敏
    本研究プロジェクトは、ソルゲル法を用いて種々の酸化物をアルミニウム上にコーティングしたのち、これを中性電解質溶液中でアノード酸化することにより、各種の複合酸化物皮膜を形成するとともに、皮膜構造と皮膜の誘電的性質との関係を明らかにすることを目的としている。本年度は、BaTiO_3およびSiO_2皮膜について検討を加え、次の結果を得た。
    1)BaTiO_3をコーティングしたアルミニウム試料を中性のホウ酸塩溶液中でアノード酸化を行うと、コーティング層と素地金属との界面にアルミナ層が成長する。このプロセスにより生成するアノード酸化皮膜の電気容量は、通常のアノード酸化により得られるバリヤー型アノード酸化皮膜のそれと同程度である。
    SiO_2皮膜をあらかじめコーティングしておくと、アノード酸化のさい、コーティング層と素地金属との界面にアルミナ層が生成するとともに、Al-Si複合酸化物層が生成する。このプロセスにより生成するアノード酸化皮膜の電気容量は、通常のアノード酸化により得られるバリヤー型アノード酸化皮膜のそれに比べて20%大きい。また、この電気容量の増大は、複合酸化物層が極めて高い電場を指示できるためである。
    日本学術振興会, 特定領域研究(A), 北海道大学, 11118205
  • パルス電流通電法による耐酸化性MoSi_2基超高温材料のその場合成
    科学研究費助成事業
    1998年 - 1999年
    黒川 一哉, 坂入 正敏, 高橋 英明
    ダイシリサイドは耐酸化性超高温材料の候補材の1種であるが、一般に融点が高いため溶融法での作製が困難であること、接合材料や複合材料の作製も容易にできることなどから、粉末冶金法による作製が有望である。本研究では、パルス電流通電による粒子間での放電現象の真偽について検討するとともに、作製したダイシリサイドの耐酸化性評価、さらに複合材料を想定した異種材料間での界面反応挙動ついて明かにするための実験を10-11年度にかけて行った。今年度は特に本方法で作製した各種ダイシリサイド焼結体の耐酸化性評価に関する研究を重点的に進めた。
    1.FeSi_2、CoSi_2、CrSi_2、Vsi_2、TaSi_2、NbSi_2、Wsi_2およびMoSi_2の耐酸化性評価を500℃から1500℃の温度範囲において行い、各ダイシリサイドにおける金属とSiの同時酸化が起きる温度領域を明らかにした。
    2.FeSi_2、CoSi_2、CrSi_2は1000℃以下の温度で優れた耐酸化性を有し、またMoSi_2は500℃±100℃を除く温度範囲で極めて優れた耐酸化性を示した。しかし、他のダイシリサイドでは500℃以上の温度範囲にわたって金属とSiの同時酸化が起こるため、優れた耐酸化性を示さなかった。
    3.MoSi_2の500℃±100℃における同時酸化には、材料の欠陥(ポアやクラック)および雰囲気の水蒸気が強い影響を及ぼしていることを明らかにした。
    4.パルス電流通電法により清浄で緻密なダイシリサイド焼結体およびその複合材料を作製することが可能であるが、特に耐酸化性超高温材料としてのポテンシャルが高いダイシリサイドはMoSi_2であることを明らかにした。
    日本学術振興会, 萌芽的研究, 北海道大学, 10875138
  • レーザー剥離法を用いたAlアノード酸化皮膜の局部再生過程の研究
    科学研究費助成事業
    1998年 - 1998年
    坂入 正敏
    日本学術振興会, 奨励研究(A), 北海道大学, 10750521
  • ゾル・ゲルコーティング/アノード酸化によるAl-(TiNb)酸化物皮膜の形成
    科学研究費助成事業
    1998年 - 1998年
    高橋 英明, 坂入 正敏
    本研究は、アルミニウムアノード酸化皮膜に種々の酸化物を取り込ませ、誘電率の高い複合酸化物皮膜を形成しようとするものである。すなわち、アルミニウム試料上にゾルゲル法により種々の酸化物皮膜をコーティングしたのち、これを中性の電解質溶液中でアノード酸化することによりAl+Me複合酸化物皮膜を形成するとともに、その誘電的性質を調べた。表題には、AI-(Tl,Nb)複合酸化物皮膜とあるが、本年度においては、ゾル溶液の調製のしやすさなどの理由により、Al-Zr複合酸化物皮膜を選択した。得られた主な結果は、次の通りである。
    1)電解研磨試料にゾルゲル法により、Zr-酸化物皮膜をコーティングするさい、加熱処理温度をT_h=573および873Kとした試料を、中性のホウ酸塩溶液中でアノード酸化すると、T_h=573Kの試料の場合には、Zr-酸化物層と素地金属との界面にAl-Zr複合酸化物外層およびAl_2O_3内層からなるアノード酸化皮膜が生成するが、T_h=873Kの場合には、Al_2O_3一層構造を有するアノード酸化皮膜が得られた。インピーダンス測定により、複合酸化物層を有する前者のアノード酸化皮膜がより大きい並列等価容量を持つことがわかった。
    2)多孔質アノード皮膜化成試料上にZr-酸化物皮膜をコーティングすると、Zr-酸化物の一部はアノード酸化皮膜の細孔中に堆積し、一部はアノード酸化皮膜上に堆積することがわかった。これをアノード酸化すると、細孔中にAl-Zr複合酸化物が生成するとともに皮膜/素地金属界面にAl_2O_3層が生成することがわかった。
    日本学術振興会, 特定領域研究(A), 北海道大学, 10131204
  • 超高温用モリブデンダイシリサイド材料における加速酸化現象の解明とその抑制
    科学研究費助成事業
    1997年 - 1998年
    黒川 一哉, 坂入 正敏, 高橋 英明
    本研究の目的は、将来の超高温材料として期待されているモリブデンダイシリサイド(MoSi_2)の耐環境性における最大の弱点である加速酸化現象を解明するとともに、その有効な抑制法を明かにすることにある。加速酸化は環境側および材料側の種々の因子が相互に関与した複雑な現象であり、本研究では特に各因子の影響を明かにするための系統的な実験を行った。本研究で得られた主な結果は以下の通りである。
    1. 酸化温度の影響:673K〜773Kの温度範囲でMoとSiの同時酸化に基づく激しい加速酸化を示す。しかし、1073K以上の温度では、Siの選択酸化によりSiO_2皮膜が形成され、極めて優れた耐酸化性を示す。
    2. 雰囲気(水蒸気)の影響:空気中に水蒸気が含まれる場合には、低密度MoSi_2で加速酸化が激しく、水蒸気分圧が高いほど短い時間でペスト(材料の粉化)に至る。
    3. MoSi_2組成の影響:Mo/Si濃度比の増加とともに耐酸化性が低下するが、その影響は小さい。
    4. 密度の影響:MoSi_2の密度は加速酸化に特に大きな影響を及ぼし、95%以上の高緻密体にすることによって加速酸化を著しく抑制できる。
    5. 同時酸化は、酸化初期にはMoSi_2の焼結時に形成されるSiO_2介在物など欠陥部で局部的に起り、次第に表面全体に拡がる。
    MoSi_2の高緻密化と雰囲気からの水蒸気除去により加速酸化をほぼ完全に防止できることを明かにするとともに、その場合成法によるMoSi基材料の作製も加速酸化の抑制に有効であることを明かにした。
    日本学術振興会, 基盤研究(B), 北海道大学, 09450263
  • パルスYAGレーザーを用いたアルミニウムの表面パターニング
    科学研究費助成事業
    1996年 - 1998年
    高橋 英明, 坂入 正敏, 黒川 一哉
    本研究は、アルミニウム基板上におけるパターニング技術の新しい方法の開発と確立と目的としており、平成8年度〜平成10年度にわたって行われたものである。すなわち、アノード酸化皮膜化成試料を金属イオンを含む溶液中に浸漬し、これにパルスYAGレーザーを照射することにより、皮膜を局部的に破壊・除去する。その後、電気メッキあるいは無電解めっきにより、皮膜除去部のみに金属を析出させ、アルミニウム上にパターンを描くとともに、有機絶縁板の接着、素地金属の溶解除去により模擬プリント配線基板を作製しようとするものである。得られた結果の主なものは次の通りである。
    1) レーザー照射のさい、皮膜は素地金属のレーザーアプレーションにより生じる高圧力により破壊・除去される。そのため、レーザー照射部の周囲の皮膜にはクラックが発生するが、レーザー照射前に皮膜を赤く着色しておくことにより、クラックの発生は防止できる。最大100μmの厚さの皮膜を15〜500μmの幅で連続的に皮膜を除去できる。
    2) レーザー照射のさい、皮膜除去部の表面に金属微粒子が析出し、これらが、次の電気メッキおよび無電解めっきのさい、核として作用し、とくに無電解めっきの初期の析出速度に大きな影響をおよぼす。析出Pd金属粒子がもっともその効力が大きい。電気メッキによりNlおよびCuの、無電解めっきによりNI-Pの緻密電析層を得ることができた。
    3) 15μmのNl電析線で描いたアルミニウム試料板に有機絶縁板を接着し、素地金属を溶解除去により生成した模擬プリント配線基板を形成し、電気伝導性を調べた結果、きわめてよい電気電導性を示した。
    日本学術振興会, 基盤研究(B), 北海道大学, 08455326
  • 高性能電解コンデンサーのためのAl-(Ti,Nb,Ta)複合酸化物皮膜の形成
    科学研究費助成事業
    1997年 - 1997年
    高橋 英明, 坂入 正敏, 黒川 一哉
    本研究は、アルミニウム上に生成するアノード酸化皮膜中にTiO_2,Ta_2O_5,Nb_2O_5などを混入させ、これらとAl_2O_3との複合酸化物を形成することにより、誘電率の大きな酸化物皮膜を形成し、新しいタイプのアルミニウム電解コンデンサーの開発を目指しているが、本年度においては、CVD/アノード酸化を組み合わせた方法により、この複合酸化物皮膜の生成を試みた。得られた主な研究成果は、次のようである。
    1.TiO_2をCVDにより、温度300°Cおよび400°Cに保ったアルミニウム上に形成すると、TiO_2皮膜の成長速度は温度が高いほど大きい。また、生成した皮膜は多孔質であり、無定型である。
    2.TiO_2皮膜をコーティング後、400°Cで空気雰囲気中加熱処理を行うと、TiO_2は結晶化してアナターゼ型の結晶構造を示す。
    3.TiO_2皮膜をコーティングした試料を、中性のホウ酸塩溶液中で定電流アノード酸化を行うと、TiO_2皮膜/素地金属界面に二層構造を示す酸化皮膜が生成する。外層は、Ti/Al-複合酸化物層であり、内層はAl_2O_3層からなる。
    4.CVD/加熱処理/アノード酸化により得られた複合酸化物皮膜は、通常のアノード酸化により得られる皮膜に比べて約65%大きな電気容量を示す。
    日本学術振興会, 重点領域研究, 北海道大学, 09237205
  • アルミニウム等の陽極酸化に関する研究               
    競争的資金
  • 金属材料の腐食・防食に関する研究               
    競争的資金
  • レーザや微小液滴セルを用いる局部表面処理・電気化学               
    競争的資金
  • Locallized corrosion of metals               
    競争的資金
  • Local Surface Treatment on al by LASER               
    競争的資金
  • Localized Corrosion on Metals by Photon Rupture Method               
    競争的資金
  • Local Surface Treatment on Al by LASER               
    競争的資金
  • Study on Anodic Oxidation behavior of Aluminum               
    競争的資金

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  • めっきによる三次元構造体の形成法               
    特許権
    2002-256325

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    2017年10月12日 - 2017年10月13日
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