通过测定Tafel极化曲线、交流阻抗谱和进行盐雾试验,研究了新型三价铬彩色钝化剂SF-571和蓝白钝化剂SF-572对镀锌层耐蚀性能的影响,并与进口钝化剂进行对比。氯化钾镀锌工艺为:KCl 200 g/L,ZnCl250 g/L,H3BO335 g/L,柔软剂30 mL/L,光亮剂1.5 mL/L,25°C,25 min,电流密度2 A/dm2。电化学分析表明,所有镀锌层钝化膜在1%NaCl溶液中均存在钝化现象,采用自制钝化剂SF-571和SF-572所得膜层的耐腐蚀性能达到或优于用进口钝化剂所得膜层。对比膜层的表面形貌可知,自制钝化剂钝化所得膜层表面更平整、致密。
The effects of novel trivalent chromium passivators SF-571 (iridescent) and SF-572 (blue-white) on corrosion resistance of zinc coating were studied by Tafel polarization method, electrochemical impedance spectroscopy, and salt spray test, and compared with the imported ones. The zinc coatings were obtained in a potassium chloride bath comprising KCl 200 g/L, ZnCl2 50 g/L, H3BO3 35 g/L, softener 30 mL/L, and brightener 1.5 mL/L at 25 °C and 2 A/dm2 for 25 min. The electrochemical analysis shows that all of the passivation films has a passivation hehavior in 1% NaCl solution. The corrosion resistance of the films obtained with SF-571 and SF-572 passivators is equivalent or superior to that obtained with the imported passivators. The comparison of surface morphology indicates that the surfaces of the films obtained with homemade passivators are smoother and denser.
参考文献
[1] | 张景双,安茂忠,杨哲龙,屠振密.电镀锌及锌合金镀层钝化处理的应用与发展[J].材料保护,1999(07):14-16. |
[2] | NABIL ZAKI .TRIVALENT CHROME CONVERSION COATING FOR ZINC AND ZINC ALLOYS[J].Metal finishing,2007(10):393-394. |
[3] | 陈锦虹,卢锦堂,许乔瑜,孔纲,眭润舟.镀锌层无铬钝化研究的进展[J].腐蚀科学与防护技术,2003(05):277-281. |
[4] | JOHNSON D M .Zinc and cadmium passivating bath:[P].US,2559878,1951-07-10. |
[5] | 江志全 .镀锌三价铬白色钝化液:[P].CN,1067274,1992-12-23. |
[6] | 厦门大学 .三价铬彩虹色钝化液:[P].CN,1390981,2003-01-15. |
[7] | 广州市集胜化工有限公司 .镀锌用三价铬彩虹色钝化剂及其制造方法:[P].CN,1584117,2005-02-23. |
[8] | 广州市集胜化工有限公司 .镀锌用三价铬蓝白色钝化剂及其制造方法:[P].CN,1594651,2005-03-16. |
[9] | 汤小卫 .三价铬钝化液及其制备方法:[P].CN,1670250,2005-09-21. |
[10] | G. D. Wilcox .Replacing Chromates for the Passivation of Zinc Surfaces[J].Transactions of the Institute of Metal Finishing,2003(1):B13-B15. |
[11] | 刘建军.三价铬钝化技术及其最新进展[J].电镀与环保,2002(06):22-23. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%