【摘要】 通过扫描电镜(SEM)分析、磷化膜增重和开路电位-磷化时间的测量及中性盐雾(NSS)试验,研究了胶质磷酸钛表调预处理对热镀锌层表面磷酸锌转化膜的影响。结果表明,热镀锌钢经胶质磷酸钛表调预处理后再磷化,与不经表调直接磷化相比,磷酸锌晶体的形核率与生长速率明显提高,可获得较细小致密的磷酸锌晶体和较大的膜层增重;且前者由于磷酸锌晶体细化和覆盖率提高,磷化膜的耐蚀性也有所增强。更多还原

【Abstract】 The influence of activating pretreatment with colloid titanium phosphate on the growth and corrosion resistance of zinc phosphate conversion coating on hot -dipping galvanized steel was investigated based on observation with a scanning electron microscope, measurements of weight gain and open circuit potential - phosphating time curve of the phospha-ting coating, and test of neutral salt spraying. It was found that the nucleation ratio and growth rate of zinc phosphate crystals on the hot-dipping galvanized steel increased when the steel was activated using the colloid titanium phosphate before phosphating, and the weight gain of the phosphating coating also increased therewith as compared with direct phosphating without activating pretreatment. At the same time, the activating pretreatment with the colloid titanium phosphate contributed to enhancing the formation of fine and compact zinc phosphate crystals, and hence the corrosion resistance of the phosphate coating was increased as well,due to the decrease in the grain size of the zinc phosphate crystals and increase in the coverage of the phosphate coating.更多还原