原位椭圆偏振光谱法研究镁合金在模拟冷却水中的腐蚀  

STUDY ON CORROSION OF MAGNESIUM ALLOY IN SIMULATED COOLING WATER BY MEANS OF IN SITU SPECTROSCOPIC ELLIPSOMETRY

作　　者：李凌杰[1,2] 雷惊雷[1] 贺东海[1] 徐辉[1] 张胜涛[1] 潘复生[2] 

机构地区：[1]重庆大学化学与化工学院,重庆400044 [2]重庆大学材料科学与工程学院,重庆400044

出　　处：《腐蚀科学与防护技术》2009年第3期236-238,共3页Corrosion Science and Protection Technology

基　　金：国家杰出青年科学基金(50725413);国家自然科学基金(20803097);教育部留学回国人员科研启动基金(教外司留[2007]1108-6);重庆市科委自然科学基金(CSTC;2008BB4174)

摘　　要：采用原位椭圆偏振光谱法研究镁合金在模拟工业冷却水中的腐蚀及添加钼酸钠对腐蚀的抑制作用,利用单层膜模型解析椭圆偏振光谱实验数据,得到"电极—介质"界面层厚度及光学常数的动态变化规律,由此将镁合金在模拟冷却水中的腐蚀分为3个阶段:自然氧化膜溶解、吸附膜形成、腐蚀产物沉积,添加钼酸钠使腐蚀过程中自然氧化膜溶解减弱、吸附膜和沉积膜变得致密,从而有效抑制镁合金腐蚀.In situ spectroscopic ellipsometry was employed to investigate the corrosion behavior of AZ40 magnesium alloy in a simulated cooling water without and with molybdate inhibitor. By deeonvoluting the ellipsometric data with a one-layer model, the evolution of the refractive indices and the thickness of the interface layer of “electrode-medium” were obtained. Based on the deconvolution results,three regimes, which were dissolution of native oxide film, formation of adsorption film and precipitation of corrosion products, were proposed for the corrosion process of magnesium alloys in the simulated cooling water. The addition of molybdate weakened the dissolution of the native oxide film and made the adsorption film and the precipitated film much compact,which was responsible for the effective inhibition of molybdate on corrosion of magnesium alloys in the simulated cooling water.

关 键 词：椭圆偏振光谱法 镁合金 模拟冷却水 腐蚀 

分 类 号：TG174.4[金属学及工艺—金属表面处理]