A7N01S-T5铝合金在84消毒液中的电化学行为  

Electrochemical Behavior of A7N01S-T5 Aluminum Alloy in 84 Disinfectant

作　　者：尹学涛 李丽 周学杰 李文翰 张三平 YIN Xue-tao;LI Li;ZHOU Xue-jie;LI Wen-han;ZHANG San-ping(WuHan Research Institute of Materials Protection,Wuhan 430030,China;National Observation and Research Station for Corrosion of Atmospheric Fresh Water Environment Materials in Wuhan,Wuhan 430030,China;Sunrui Marine Environment Engineering Co.,Ltd.,Qingdao 266101,China;CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China)

机构地区：[1]武汉材料保护研究所有限公司,湖北武汉430030 [2]湖北武汉大气淡水环境材料腐蚀国家野外科学观测研究站,湖北武汉430030 [3]青岛双瑞海洋环境工程股份有限公司,山东青岛266101 [4]中车青岛四方机车车辆股份有限公司,山东青岛266111

出　　处：《材料保护》2020年第4期53-57,83,共6页Materials Protection

摘　　要：为了研究消毒液对高铁车厢铝合金腐蚀的影响,采用动电位极化和电化学阻抗2种电化学测量技术,研究了高铁车体A7N01S-T5铝合金在不同浓度(100,200,400,800,1000 mg/L)84消毒液中的电化学行为,取自来水作为对照试验,使用VHX-2000C超景深三维体式显微镜观察试验后铝合金电极的微观形貌。结果表明:电化学阻抗谱中的Nyquist谱电极过程受活化和扩散控制,随着消毒液浓度升高电荷转移电阻和低频阻抗值减小并趋于一致;极化曲线的阴极过程和阳极过程分别以析氢反应和氧化还原反应为主,随着消毒液浓度升高,自腐蚀电位在不断负移后趋于一致,点蚀电位不断负移,腐蚀电流密度逐渐增大后趋于一致;随着消毒液浓度升高合金表面腐蚀由点蚀发展为全面腐蚀,腐蚀区域扩展缓慢,腐蚀速度减缓。In order to research the effect of disinfectant on the corrosion of aluminium alloy used for high-speed rail carriages,the electrochemical behavior of A7N01S-T5 aluminium alloy in 84 disinfectant of different concentrations(100,200,400,800,1000 mg/L)was studied by potentiodynamic polarization and electrochemical impedance measurements.Meanwhile,tap water was taken as a control experiment.The micro-morphology of the electrode was observed by VHX-2000C ultra-field three-dimensional stereomicroscope.Results showed that the electrode process of Nyquist diagram in electrochemical impedance spectroscopy was controlled by activation and diffusion,and the charge transfer resistance and low frequency impedance decreased and tended to be the same with the increase of disinfectant concentration.The cathodic and anodic processes of polarization curve were mainly hydrogen evolution reaction and redox reaction,respectively.With the increase of disinfectant concentration,the self-corrosion potential tended to converge after a continuous negative shift.Moreover,the pitting-corrosion potential shifted negatively,and the corrosion current density rose gradually and then tended to converge.As the concentration of disinfectant increased,the aluminium alloy corrosion developed from pitting corrosion to overall corrosion,and the corrosion area expanded slowly as well as the corrosion rate declined.

关 键 词：铝合金 电化学行为 84消毒液 不同浓度 腐蚀 

分 类 号：TG172[金属学及工艺—金属表面处理]