论文部分内容阅读
在干湿交替和逐渐增加氯离子浓度的条件下 ,对 4种热浸镀Zn基合金层进行了电化学测试评价 .电极电位和腐蚀速率的试验结果表明 4种热镀层防护性能的顺序为ZnAlMg镀层 ,ZnAlSi镀层 ,ZnAl镀层 ,Zn镀层 .电极电位的测试可以较好的观察和评价镀层的完整性 ,镀Zn层、镀ZnAl层、镀ZnAlSi、镀ZnAlMg层分别在第 9、13、2 1周期出现红锈 ,而ZnAlMg镀层 4 8周期仍未出现红锈 .随着氯离子浓度和试验周期的增加 ,各种涂层的腐蚀速率呈周期性变化 ,其中ZnAlMg镀层的腐蚀速率最小 .交流阻抗谱较线性极化测试结果的主要区别在于得到腐蚀速率相对较少 ,变化趋势基本一致
Electrochemical tests were carried out on four hot-dip Zn-based alloy layers under alternating wet and dry conditions and gradually increasing chloride ion concentration.The results of electrode potential and corrosion rate show that the protective properties of the four hot-dip coating layers are ZnAlMg Coating, ZnAlSi coating, ZnAl coating, Zn coating.The test of electrode potential can better observe and evaluate the integrity of the coating, Zn coating, ZnAl coating, ZnAlSi coating, ZnAlMg coating layer 9,13,13 Red rust occurs in the cycle, while rust is not observed in 48 cycles of ZnAlMg coating.Corrosion rate of all coatings changes periodically with the increase of chloride ion concentration and test period, and the corrosion rate of ZnAlMg coating is the least. The main difference between the spectra and the results of the linear polarization test is that the corrosion rate is relatively small and the trend of change is basically the same