The Anti-Corrosion Study on Zn-Al-Mg Coated Steel Sheets

Abstract:

Z11A3M, Z6A3M, Z1.6A1.6M, and Z1A1M coating samples were prepared in HDPS by traditional continuous hot dipping method. The anti-corrosion ability of these coatings was determined by SST, polarization curve and electrochemical impedance. The corrosion products were analyzed by XRD. The surface and section microstructures were observed by SEM. The results showed, the corrosion resistance of 4 kinds of Zn-Al-Mg coated steel is 4 times as galvanized steel. The Zn-Al-Mg coated steel sheets can be self-cured. MgZn₂ and eutectic could be found in all ZAM coating. Zn/Al/Zn₂Mg eutectic can be found in all 4 kind of coatings. The reason for superior corrosion resistance of Zn-Al-Mg coated steel is the decomposition reaction of Zn₅(OH)₈Cl₂ which is retained by Mg. Thus the O₂ diffusing rate is lowered down. Mg acts as PH buffer and the Zn dissolving rate can be reduced. According the results, the application of Zn-Al-Mg coated steel sheets is forecasted.

• Periodical: Applied Mechanics and Materials (Volumes 490-491)
• Pages: 186-191
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.490-491.186
• Online since: January 2014
• Authors: Feng Li*, Fang Zhou, Jia Shun Lv, Hong Gang Yang, Leng Zhang, En Dong Wang
• Keywords: Corrosion Behavior, Galvanized Steel Sheet, Microstructure, Zn-Al-Mg

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