Cl^-含量对2A12铝合金初期腐蚀行为的影响  

Influence of Cl^- concentration on the initial corrosion behavior of 2A12 aluminum alloy

作　　者：李涛[1,2] 李晓刚[1] 董超芳[1] 周建龙[1] 冯佃臣[2] 吴军[1,3] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]内蒙古科技大学材料与冶金工程学院,包头014010 [3]南昌航空大学材料科学与工程学院,南昌330063

出　　处：《北京科技大学学报》2009年第12期1576-1582,共7页Journal of University of Science and Technology Beijing

基　　金：科技部国家科学基础条件平台建设项目(No.2005DKA10400)

摘　　要：通过干湿周浸加速实验方法、扫描电镜观察和电化学阻抗谱测试技术,研究了2A12铝合金的初期腐蚀规律与电化学行为.实验结果表明,干湿周浸48h后,所有Cl-溶液中试样都发生了明显的点蚀.提高Cl-含量可以促进点蚀的形成和发展,同时腐蚀产物增多.当Cl-含量低时,腐蚀过程主要受电荷转移电阻控制;随Cl-含量增加,其电化学特征转变为受电荷转移电阻和Warburg阻抗扩散混合控制.The initial corrosion laws and electrochemical behaviors of 2A12 aluminum alloy were investigated by using alternate immersion test, scanning electron microscopy （SEM） as well as electrochemical impedance spectroscopy （EIS）. The results showed that obvious pitting phenomena were observed for all the specimens in various Cl^- containing solutions after 48h alternate immersion. With the increase of Cl^- concentration, the initiation and development of pitting corrosion were promoted and more corrosion products formed. At a lower Cl- concentration, the corrosion process was mainly controlled by charge transfer resistance; with increasing Cl^- concentration, the electrochemical characteristic transferred to the mixed control of charge transfer resistance and Warburg resistance.

关 键 词：铝合金 周浸实验 电化学阻抗谱 点蚀 初期腐蚀 

分 类 号：TG172.3[金属学及工艺—金属表面处理]