电力系统用LF21铝合金的电化学腐蚀行为  

Electrochemical Corrosion Behavior of LF21 Aluminum Alloy Used in Electric Power System

作　　者：杨萍[1] 黎学明[1] 宗庆彬[1] 邱妮 姚强 苗玉龙 

机构地区：[1]重庆大学化学化工学院,重庆400030 [2]重庆电力科学试验研究院,重庆401123

出　　处：《腐蚀科学与防护技术》2012年第4期309-313,共5页Corrosion Science and Protection Technology

基　　金：重庆市电力公司重点科技项目(2010渝电科技30#);重庆市交通委员会科技计划项目;重庆市自然科学基金项目(2004BB6065)资助

摘　　要：采用Tafel直线外推法、电化学阻抗谱和中性盐雾腐蚀试验研究了电力系统用LF21铝合金在5%NaCl溶液中的电化学腐蚀行为,利用SEM和EDS表征材料的腐蚀形态与腐蚀产物组成,并探讨腐蚀机理.结果表明,LF21铝合金在5%NaCl溶液中耐蚀性很差.随着电解液温度升高,铝合金的自腐蚀电位负移,腐蚀速率变大.电化学阻抗谱显示其容抗减小,膜电容下降,合金表面的保护膜被破坏.LF21铝合金在NaCl介质中的腐蚀主要以点蚀为主,形成较深的腐蚀坑,点蚀部位O含量明显增高.The electrochemical behavior of LF21 aluminum alloy,as a major base materials used in electric power system,in 5% NaCl solution were investigated by Tafel linear extrapolation method,electrochemical impedance spectroscopy technique and neutral salt spray test.The surface morphology and chemical composition of the corrosion product of the alloy were examined by scanning electron microscope and energy dispersive spectrometer,respectively.The results showed that LF21 aluminum alloy exhibited poor anti-corrosion performance in 5%NaCl solution.When the temperature of solution increased,the corrosion potential of LF21 aluminum alloy shifted negatively,and the corrosion current density increased.Meanwhile,the capacitive resistance and film capacity decreased with the increasing of the solution temperature,implying that the protection film on the surface of material was deteriorated to some extent.The major corrosion form of LF21 aluminum alloy in NaCl solution was pitting corrosion,and the corrosion resulted in much deeper corrosion pits.

关 键 词：LF21铝合金 腐蚀 NACL溶液 电力系统 

分 类 号：TG172.3[金属学及工艺—金属表面处理] TG172.9[金属学及工艺—金属学]