电化学阻抗谱研究铈盐转化膜形成过程中的影响因素  

Influencing Factors During Procession of Cerium(Ⅲ) Film Formation of Aluminum Alloys by EIS

作　　者：顾宝珊 刘建华[3] 

机构地区：[1]中国钢研科技集团公司,北京100081 [2]先进金属材料涂镀国家工程实验室,北京100081 [3]北京航空航天大学材料科学与工程学院,北京100083

出　　处：《中国稀土学报》2009年第5期679-683,共5页Journal of the Chinese Society of Rare Earths

摘　　要：应用电化学阻抗谱(E IS)连续测试B95铝合金在0.01 mol.L-1CeC l3溶液中铈盐转化膜的形成过程,通过成膜过程中交流阻抗值的变化研究了温度,溶解氧O2的变化对B95铝合金稀土转化膜成膜过程的影响机制,采用等效电路的方式对测试的E IS进行了解析。结果表明:温度在20,25,30℃时B95铝合金在0.01 mol.L-1CeC l3溶液中的阻抗谱等效电路与成膜形成阶段的相同;温度为35,40,45℃B95铝合金的阻抗谱与成膜成长阶段的等效电路相同,表明升高温度缩短了稀土膜形成阶段的时间,铝合金基体溶解迅速被抑制;升高温度有利于铈盐氧化膜的形成;通O2对稀土Ce转化膜的形成无明显促进作用,O2参与的反应不是Ce转化膜形成的决速步骤。Electrochemical impedance spectroscope （EIS） of B95 aluminum alloy in 0.01 mol·L^-1 CeCl3 solution was investigated to study the film formation. The changes of EIS in the film formation helped to study the influence of temperature and variation of dissolved O2 on the film formation of B95 aluminum alloys. Followed was an analysis on the tested EIS based on equivalent circuit. The result showed that the EIS equilibrium circuits formed when B95 aluminum alloy in 0. 01 mol·L^-1 CeCl3 solution at the temperatures of 20, 25 and 30 ℃ respectively were identical with the EIS circuit formed in the film formation stage. The EIS equilibrium circuits at the temperatures of 35, 40 and 45 ℃ respectively were identical with the circuit in the film formation stage, indicating that raising the temperature could shorten the time of film formation and the dissolve of the alloys could be immediately inhibited. Raising the temperature helped to form the cerium oxide film. 02 served no contributing factor to the formation of conversion film of Cerium. The reaction involving O2 could not determine the formation of conversion coating of Cerium.

关 键 词：铝合金 交流阻抗 Ce转化膜 形成过程 温度 溶解氧 稀土 

分 类 号：O646.6[理学—物理化学] TG133.2[理学—化学]