Electrochemical corrosion properties of CeO2-containing coatings on AZ31 magnesium alloys prepared by plasma electrolytic oxidation

► Plasma electrolytic oxidation of AZ31 Mg alloy was conducted in CeO2 particle-containing electrolyte. ► Corrosion properties of CeO2-containing PEO were evaluated by potentiodynamic and EIS tests. ► Corrosion resistance of AZ31 Mg alloy was significantly improved by CeO2 incorporation. ► CeO2-containing PEO coating was more protective against Cl− ion penetration during immersion test.