Microstructure and corrosion resistance of PEO coatings formed on KBM10 Mg alloy pretreated with Nd(NO3)3

Abstract

Plasma electrolytic oxidation (PEO) technique is one of the importantmethods used in the surface modification ofmagnesiumalloys. In this paper, the ceramic coatings on pretreated KBM10magnesium alloy with Nd(NO3)3 solution were prepared by PEO. The effects of Nd(NO3)3 solution concentration on themicrostructure and corrosion resistance of PEO coatings onmagnesiumalloys were investigated by means of scanning electron microscopy (SEM), X-ray diffractometer (XRD), and electrochemical workstation. It was found that the surface of the coatings was porous after PEO, and element Nd could be deposited on the surface of the coatings by pretreatment and existed in the PEO coatings. The coating formed at Nd(NO3)3 solution concentration of 0.06mol/L exhibited the best corrosion resistance among all the as-prepared coatings.