Influence of Cr Nanoparticles on Plasma Electrolytic Oxidation Coatings on AM50 Mg Alloy

The addition of Cr nanoparticles to a plasma electrolytic oxidation (PEO) electrolyte offers the possibility producing layers with broader range coating compositions and improved properties. In this study, effects various voltages on formation, microscopic morphology, phase composition were investigated in situ incorporation into PEO-coated Mg alloy. results show that corrosion performance was significantly when final voltage set 460 V concentration 1 g/L. Compared particle-free coating, current density g/L reduced by two orders magnitude. impedance at low frequency (0.01 Hz) increased more than one order magnitude after hour immersion, indicating considerable improvement resistance. Due high temperature during coating-formation process, oxidized, resulting formation Cr2O3. existence Cr2O3 slightly growth rate sealed open pores coating.