在碱性溶液中Cu-Ni合金镀层钝化膜的半导体性能研究  

Semi-conducting Property of Passive Film Formed on Copper-Nickel Alloy Coatings in Alkaline Solution

作　　者：吴红艳[1] 王毅[1] 钟庆东[1] 周琼宇[1] 朱振宇[1] 杜海龙[1] 

机构地区：[1]上海大学上海市现代冶金与材料制备重点实验室,上海200072

出　　处：《腐蚀科学与防护技术》2012年第5期385-391,共7页Corrosion Science and Protection Technology

摘　　要：用电化学方法测量Cu-Ni合金镀层在1 mol/L的NaOH溶液中的Tafel、EIS和Mott-Schottky曲线,研究了镀层钝化膜的电化学性能,并借助点缺陷模型(PDM)计算了钝化膜的受主浓度、平带电位及阳离子空位扩散系数.结果表明:Cu-Ni合金镀层表面钝化膜具有p型半导体性质.受主浓度和平带电位随成膜电位的负移而增大.随着合金镀层Cu含量的增加,受主浓度和钝化膜阻抗减小,钝化膜耐蚀性降低.不同Cu含量的Cu-Ni合金镀层阳极氧化后的钝化膜阳离子空位扩散系数为10-14cm2/s.Several electrochemical means such as Tafel-, EIS- and Mott-Schottky-measurements were used to investigate the semi-conducting property of the passive film formed on Cu-Ni alloy coatings in 1 mol/L NaOH solution. At the same time, the Point Defect Model （PDM） was adopted to calculate the acceptor density, flat potential and vacancy diffusion coefficient in the passive film formed on Cu-Ni alloy coatings. The results show that the passive films formed on Cu-Ni coatings display p-type semi-conducting characteristics, corresponding to a preponderance of metal vacan- cies （over oxygen vacancies and interstitials） in the barrier layer. With the increase of Cu, the flat potential moves toward positive, the acceptor density and impedance of passive films decrease, the negative moving of the film formation potential causes an increase in acceptor density. The calculat- ed value obtained for Do is about 10^-14 cm2/s.

关 键 词：Cu-Ni镀层 钝化膜 极化 半导体性 扩散系数 

分 类 号：TG174.4[金属学及工艺—金属表面处理]