华南理工大学学报(自然科学版) ›› 2007, Vol. 35 ›› Issue (5): 104-108.

• 化学化工 • 上一篇    下一篇

镀锌层三价铬与六价铬钝化膜的性能

曾振欧1 邹锦光1 赵国鹏2 刘建平2   

  1. 1.华南理工大学 化学科学学院,广东 广州 510640; 2 广州二轻工业科学技术研究所,广东 广州 510170
  • 收稿日期:2006-06-05 出版日期:2007-05-25 发布日期:2007-05-25
  • 通信作者: 曾振欧(1955-),男,教授,主要从事应用电化学和表面处理方面的研究. E-mail:zhouzeng@scut.edu.cn
  • 作者简介:曾振欧(1955-),男,教授,主要从事应用电化学和表面处理方面的研究.

Performance of Trivalent and Hexavalent Chromium Passivation Films Based on Zinc Plating

Zeng Zhen-ou1  Zou lin-guang1  Zhao Guo-peng2  Liu lian-ping2   

  1. 1. School of Chemical Science , South China Univ. of Tech. , Guangzhou 510640 , Guangdong , China;2. Guangzhou Etsing Plating Research Institute , Guangzhou 510170 , Guangdong , China)
  • Received:2006-06-05 Online:2007-05-25 Published:2007-05-25
  • Contact: 曾振欧(1955-),男,教授,主要从事应用电化学和表面处理方面的研究. E-mail:zhouzeng@scut.edu.cn
  • About author:曾振欧(1955-),男,教授,主要从事应用电化学和表面处理方面的研究.

摘要: 为了以三价格替代镀锌层钝化溶液中的六价络,实现镀锌工艺的清洁生产,利用中性盐雾实验(NSS) 、Tafel 曲线和扫描电镜对镀锌层三价铬和六价铬钝化膜的耐腐蚀性能、电化学行为、耐高湿性能和表面结构进行了比较研究. NSS 实验结果表明,三价铬钝化膜的耐腐蚀性能高于六价铬钝化膜, NSS 时间可达84h;Tafel 曲线表明,三价铬钝化膜的腐蚀速率低于六价铬钝化膜,耐高温性能则高于六价铬钝化膜;SEM 照片显示,三价铬钝化膜的表面形貌为致密结构,高温处理后膜层变化不大,而六价铬钝化膜表面为疏松的网状结构.

关键词: 镀锌, 三价铬, 六价铬, 钝化

Abstract:

In order to replace the hexavalent chromium in passivation solution with trivalent chromium and achieve pollution-free production for zinc plating , the cOITosion resistances , electrochemical behaviors , heat-resistant abilities and microstructures of trivalent and hexavalent chromium passivation films were studied via neutral salt spray (NSS) test , Tafel plot curves and SEM. The results of NSS test show that trivalent chromium passivation film can
pass 84 h of NSS test and possesses better cOITosion resistance than the hexavalent one. The Tafel plot curves indicate that trivalent chromium passiva.tion film is of a lower cOITosion rate but a higher heat-resistant ability than the hexavalent one. Moreover , the SEM micrographs show that trivalent chromium passivation film is compact even after heat treatment , while the microstructure of hexavalent chromium passivation film is loose reticular.

Key words: zinc plating, trivalent chromium, hexavalent chromium, passivation