Research on Cerium Conversion Coating on ZM5 Magnesium Alloy

Abstract:

The conversion coating formed by immersion in a solution containing cerium salt on ZM5 magnesium alloy was studied and the corrosion resistance was evaluated as well. These micrographs of specimen surface were investigated by metallographic microscope. The corrosion behaviors of ZM5 magnesium alloy and conversion coating were assessed by means of potentiodynamic polarization curves and immersion tests. The experimental results indicated that a yellow-brown conversion coating was formed subsequently on the specimen surface. The results of electrochemical measurements and immersion tests revealed that the cerium conversion coating possessed better corrosion resistance than the substrate. In this study, cerium conversion coatings formed on ZM5 magnesium alloy were characterized and the formation mechanism was discussed.

• Periodical: Advanced Materials Research (Volume 936)
• Pages: 1082-1085
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.936.1082
• Online since: June 2014
• Authors: Rong Xia Zhu*, Guo Mian Gao, Zheng Miao
• Keywords: Conversion Coatings, Corrosion Resistance, Magnesium Alloy

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