不同镀锌工艺三价铬钝化耐腐蚀性研究  

Study on corrosion resistance of trivalent chromium passivation films on zinc coatings electroplated by different processes

作　　者：吴育忠[1,2] 黄美玲[1,2] 李伟善[1,2] 马冲 左正勋 

机构地区：[1]华南师范大学化学与环境学院,广东广州510006 [2]广东高校电化学储能与发电技术重点实验室,广东广州510631 [3]佛山南海美德耐化工原料有限公司,广东佛山528247

出　　处：《电镀与涂饰》2009年第7期39-41,共3页Electroplating & Finishing

摘　　要：采用中性盐雾试验和电化学阻抗谱,研究了酸性氯化钾镀锌、碱性无氰镀锌和碱性氰化物镀锌3种工艺所得镀锌层经三价铬彩色钝化后钝化膜的耐蚀性。结果表明:钝化后,酸性氯化钾镀锌层的耐蚀性最好,碱性无氰镀锌层次之,碱性氰化物镀锌层最差。在质量分数为1%的氯化钠溶液中,镀锌层钝化膜电阻的大小顺序为:酸性氯化钾镀锌>碱性无氰镀锌>碱性氰化物镀锌。酸性氯化钾镀锌钝化膜的耐蚀性较好可以与所得镀层中有机杂质夹杂较少有关。The Zn coatings electroplated respectively from acid potassium chloride, alkaline non-cyanide and alkaline cyanide electrolytes were passivated with a trivalent chromium iridescent passivating agent. The corrosion resistance of the passivation films was studied by neutral salt spray （NSS） test and electrochemical impedance spectroscopy （EIS）. The results showed that the corrosion resistance of the passivation films and their electrical resistance in a 1% （mass fraction） NaCl solution for different Zn electroplating processes are in the following descending order： acid potassium chloride 〉 alkaline non-cyanide 〉 alkaline cyanide. The better corrosion resistance of the acid potassium chloride Zn plating coating may be attributed to the less incorporation of organic impurities.

关 键 词：镀锌 三价铬 彩色钝化 耐蚀性 中性盐雾试验 电化学阻抗谱 

分 类 号：TQ153.15[化学工程—电化学工业] TG178[金属学及工艺—金属表面处理]