Preparation and characterization of permanganate conversion coating for biodegradable AZ31B magnesium alloy

摘要

A permanganate conversion coating was prepared on biodegradable AZ31B magnesium alloy to improve its anti-corrosion property. Morphology, composition and corrosion resistance of the coating were studied in this paper. The SEM research showed that the coating was approximately 10-12μm in thickness with net-like microcracks. The XRD analysis indicated that the coating was mainly composed of MgO, MnO and Mn_2O_3. Electrochemical test showed manganese conversion treatment could significant improve the corrosion resistance of AZ31B.