Plasma electrolytic oxidation (PEO) technique is one of the important methods used in the surface modification of magnesium alloys. In this paper, the ceramic coatings on pretreated KBM10 magnesium alloy with Nd(NO₃)₃ solution were prepared by PEO. The effects of Nd(NO₃)₃ solution concentration on the microstructure and corrosion resistance of PEO coatings on magnesium alloys 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 0.06 mol/L exhibited the best corrosion resistance among all the as-prepared coatings.
Keywords: Nd(NO3)3 solution; corrosion resistance; magnesium alloy; microstructure; plasma electrolytic oxidation; pretreatment.