摘要
钼酸盐钝化能够显著提高镀锌层的耐腐蚀能力。一定工艺下获得的钼酸盐钝化膜的耐蚀性与铬酸盐钝化膜的耐蚀性相当 ,在酸性腐蚀介质下甚至可优于铬酸盐钝化。钼酸盐钝化膜中存在裂纹会降低钝化膜在中性盐雾腐蚀或盐水浸泡腐蚀中的耐蚀能力 ,而在酸性盐雾腐蚀下钝化膜的耐蚀能力则主要取决于钝化膜厚度。钼酸盐钝化膜能阻滞锌层在 5 %NaCl水溶液中腐蚀的阴极过程 。
Molybdating for galvanized steel can improve the corrosion resistance of the zinc deposit on the steel. The corrosion resistance of molybdating coatings formed in certain technical treatments is almost as the same as that of chromating coatings on the zinc deposit in Neutral NaCl Salt Spray(NSS) tests and NaCl solution immersion tests, and even better than that of chromating coatings in Acid NaCl Salt Spray (ASS) test. If cracking occurs in the molybdating coatings, it will lower the corrosion resistance of the coatings in NSS tests and NaCl solution immersion tests. However, the corrosion resistance mainly depends on the thickness of the coatings. The molybdating coatings can retard the cathodic reaction during the corrosion, and the corrosion current will be thus decrease.
出处
《材料保护》
CAS
CSCD
北大核心
2001年第11期7-9,共3页
Materials Protection
基金
广东省攻关资助项目粤财工 [98]2 78号
