Effect of phosphate additive on the morphology and anti-corrosion performance of plasma electrolytic oxidation coatings on magnesium-lithium alloy

The widespread use of magnesium-lithium (Mg-Li) alloys is frequently hampered by the grand challenge associated with their high propensity to corrosion. Herein, we describe a method to access anti-corrosion coatings on Mg-8.5Li alloy employing plasma electrolytic oxidation (PEO) technique with phosphate additive. Our results reveal the oxide coating has a compact and uniform structure after 10-min PEO treatment, along with higher thickness ((similar to)28 mu m), hardness, and wettability (28 degrees). Electrochemical measurements demonstrate the coating endows a significant enhancement in corrosion resistance for the Mg-8.5Li alloy along with a decent long-term protection for 300 h.