镀锌钢在东莞大气及模拟大气中的腐蚀行为

采用失重法、金相检验、扫描电镜法(SEM)、X射线衍射法(XRD)、能量色散谱法(EDS)以及电化学阻抗谱法(EIS)研究了镀锌钢在东莞大气环境和模拟大气环境中暴露不同时间后的腐蚀行为。结果显示:在东莞大气中,镀锌钢在暴露早期发生了局部腐蚀,随着暴露时间的延长,腐蚀速率先迅速降低然后逐步稳定,耐蚀性先降低后增强;腐蚀12个月后,主要腐蚀产物为ZnO和Zn4SO4(OH)6;在模拟大气环境中,镀锌钢的腐蚀速率和耐蚀性随时间的变化规律和东莞实地大气暴露试验的结果具有良好相关性。

Corrosion Behavior of Galvanized Steel in Dongguan Atmosphere and Simulated Atmosphere

The corrosion behavior of galvanized steel in Dongguan atmospheric environment and simulated atmospheric environment was studied by weight-loss method,metalloscopy,scanning electron microscopy (SEM),X-ray diffraction (XRD),energy dispersive spectroscopy (EDS) and electrochemical impedance spectroscopy (EIS).The results show that localized corrosion occurred in the early exposure in Dongguan atmosphere.With the extension of exposure time,the corrosion rate of galvanized steel firstly decreased rapidly and then gradually stabilized.At the same time,the corrosion resistance of galvanized steel firstly decreased and then increased.The main corrosion products of galvanized steel were ZnO and Zn4 SO4 (OH)6 after being exposed in Dongguan atmosphere for 12 months.In the simulated atmospheric environment,the trend of corrosion rate and corrosion resistance of galvanized steel with time had good correlation with the results of field exposure test in Dongguan.