摘要:锌镀层的耐腐蚀性能不强,需要进行钝化处理,但是传统的铬酸盐钝化对环境污染大等缺点需要对锌层进行无铬钝化。本次以钼酸盐为主要成分,对锌层钝化工艺技术进行了系统的研究。讨论了钝化液中磷酸盐、钼酸盐、钝化温度、钝化处理时间、钝化液pH值等对钝化成膜及膜层耐蚀性的影响。使用控制变量法得出该钝化工艺的最佳参数,在此参数基础上看是否符合工艺对钝化膜的要求。实验结果表明,当工艺参数为:钼酸铵16~24g/L,磷酸钠1.0~2.0g/L,添加剂1.5~2.5g/L,温度45~60℃,pH 3~5,时间30~60s时,便可得到一层钝化膜颜色为彩虹色、鲜艳、均匀且有光泽的镀层。该镀层能够通过附着力测试43次,中性盐雾试验达到53小时,能够达到本次课题对钝化膜层的性能要求,而且该钝化液拥有对环境污染小、处理方便等优点。8756
关键词:无铬钝化;镀锌层;钼酸盐
Study on Chromium-free Passivation Layer of Chloride Electro-galvanized
Abstract :Corrosion resistance of zinc coating is not good, the need for passivation, but the traditional chromate disadvantages such as environmental pollution requires zinc layer passivation . The molybdate as the main ingredient in the zinc layer passivation process technology for the system. Passivation solution discussed phosphates, molybdates, passivation temperature , passivation treatment time , passivation solution pH on the passivation film deposition and corrosion resistance . Using the control variable method to get the optimal parameters of the passivation process , based on the point of view in this parameter meets the requirements of the passive film technology . Experimental results show that when the process parameters are : sodium molybdate 16~24g / L, sodium phosphate 1.0~2.0g / L, additive 1.5~2.0g / L, temperature 45~60 ℃, pH 3~5, times 30~60s , they can get a layer of passivation film color is rainbow colored , bright , uniform and glossy coating . The coating adhesion test through 43 and Reached 53 hours neutral salt spray test , to achieve this task the performance requirements of the passive film , and the passivation solution has little environmental pollution and easy handling .
Key words : Non-chromium passivating ; Zinc plated coating ; Molybdate
目录
1 引言 1
1.1 课题概况及研究的意义 1
1.2 课题研究的内容及目的 1
1.3 课题在国内外研究的情况及发展趋势 1
1.3.1 无机盐类钝化 1
1.3.2 有机物钝化 2
1.4 课题主要的技术要求 4
2 技术原理 5
2.1 钾盐镀锌的技术原理 5
2.1.1 镀锌时的电极反应 5
2.1.2 添加剂光亮的作用 5
2.2 钝化机理 8
2.2.1 钝化成膜的机理 8
2.2.2 钝化成膜理论 9
2.2.3 钝化液中各组分的作用 9
3 工艺研究方法 11
3.1 工艺研究方法 11
3.2 钝化膜性能测定、试验方法 11
4 实验研究 12
4.1 实验仪器、试剂 12
4.1.1 主要实验仪器 12
4.1.2 主要药品、材料 12
4.2 镀层的制备 13
4.2.1 基础溶液的配制 13
4.2.2 添加剂的准备 13
4.2.3 钝化用试片的电镀 13
4.3 钝化膜的制备 13 氯化钾镀锌无铬钝化工艺研究:http://www.751com.cn/huaxue/lunwen_7204.html