锌合金表面稀土转化膜的组成与性能研究

Study on the Constituents and Properties of the Rare Earth Conversion Coatings on Zinc Alloy

通过在铈盐溶液中进行化学转化处理在电池锌合金表面获得了稀土转化膜 .测量了膜的结合强度、在氯化钠溶液中的极化曲线、极化电阻和腐蚀速率 ,利用XPS、XRD和SEM对稀土转化膜的化学成分和组织结构进行了分析 .结果表明 ,稀土转化膜的形成使锌合金的耐蚀性大大提高 ,已达到普通铬酸盐转化膜的耐蚀水平 .稀土转化膜主要由CeO2 、Ce2 O3、ZnO等氧化物组成 .

The rare earth conversion coatings are formed on a zinc alloy by immersing specimens in cerium salt solution. Binding force,and polarization curve,resistance and corrosion rate in sodium chloride solution are measured. The chemical composition and phase constituent of the coatings are also examined by XPS,XRD and SEM. The findings show that the corrosion resistance of the zinc alloy is greatly improved because of the formation of rare earth conversion coatings on it, which is mainly composed of CeO 2, Ce 2O 3 and ZnO. The corrosion protection level of the rare earth conversion coating will be as good as that of chromate conversion coating.