Study on Preparing Technology and Corrosion Resistance of Ti/Zr Based Chromium-free Chemical Conversion Coating on Zinc Electroplating Layer

Authors

Yong GUAN, State Key Laboratory for Corrosion and Protection,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;
Jian-guo LIU, State Key Laboratory for Corrosion and Protection,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;
Chuan-wei YAN, State Key Laboratory for Corrosion and Protection,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;

Abstract

In this paper,we obtained environmental-friendly chromium-free chemical conversion coating on the non-cyanide alkaline zinc electroplating layer by employing the optimized Ti/Zr based conversion technique.At the same time,the performances of the Ti/Zr based conversion coating were compared with chromate colour passivation coating.The corrosion resistances of the conversion coatings were investigated by using neutral salt spray(NSS) test,potentiodynamic polarization and electrochemical impedance spectroscopy(EIS).The results showed that the white rust appeared after 96 hours when the NSS test was performed on the Ti/Zr based conversion coating,which was close to the corrosion resistance rating of chromate colour passivation coating.Compared with the chromate passivation coating,the Ti/Zr based conversion coating showed lower corrosion current and higher polarization resistance.However,the passivation characteristic of the former was less evident than the latter.

Keywords

zinc electroplating, chromium-free chemical conversion, Ti/Zr based, salt spray test, corrosion resistance

DOI Link

https://doi.org/10.61558/2993-074X.2056

Publication Date

2010-11-28

Online Available Date

2010-11-28

Revised Date

2010-11-28

Received Date

2010-11-28

Recommended Citation

Yong GUAN, Jian-guo LIU, Chuan-wei YAN. Study on Preparing Technology and Corrosion Resistance of Ti/Zr Based Chromium-free Chemical Conversion Coating on Zinc Electroplating Layer[J]. Journal of Electrochemistry, 2010 , 16(4): 373-377.
DOI: 10.61558/2993-074X.2056
Available at: https://jelectrochem.xmu.edu.cn/journal/vol16/iss4/2

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