摘要
采用SEM,EDS和电化学测量技术,对热浸Zn-0.2Al-Mg-Re合金镀层钢丝的组织结构和电化学性质进行了分析与研究。结果表明Zn-0.2Al-Mg-Re合金镀层结构分为三层:外层为单相β-Zn固溶体,中间层为δ相(FeZn_7),内层为Γ相(Fe5Zn_(21)),镀层电位在0.5％NaCl溶液中恒电流电解腐蚀曲线和在5％NaCl溶液腐蚀过程中原位测量的电位与时间曲线上都出现了三个台阶,证实了低铝锌基合金镀层为多相层结构,且各相层具有不同的电化学性质,发现镀层在5％NaCl溶液腐蚀中的电极电位由表及里逐渐正移,阳极极化不具备明显的钝化特征,电极反应主要是受阴极的氧还原反应控制,这可能是由镀层的组织和保护膜的稳定性而引起的。
SEM, EDS and electrochemical measurements were used to investigate the structure and electrochemical characteristic of the hot-dipped Zn-0.2Al-Mg-Re alloy coating. The results indicated that the coating was composed of three layers: surface β-Zn sosoloid layer, middle 5 phase (FeZn7) layer and inner Γ phase (Fe5Zn21) layer. There were three steps both in the constant current electrolysis corrosion curve and the corrosion potential curve of the coating in 5%NaCl solution, which showed that different phase layers of the coating had discrepant electrochemical characteristic. The corrosion potential of the coating in 5%NaCl solution increased from the surface to the inner phase layer. There was no obvious passive characteristic in the anodic polarization curve and the corrosion process was controlled by the reduction reaction of oxygen, which would probably be caused by the structure and corrosion products of the coating.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2004年第2期148-151,共4页
Journal of University of Science and Technology Beijing
基金
国家自然科学基金(No.59899144)
