Evaluation of PEO Nanocomposite Coating on AZ31 Magnesium Alloy

The synthesis of ceramic coatings via conversion of metallic surface is the main route of corrosion resistance in the magnesium alloys. Using ceramic nano-particles as sealant in these coatings is very useful. In this study, the effect of applied current density and treatment duration on the alumina nanoparticle incorporation, corrosion resistance, and wear behavior of plasma electrolytic oxidation coating on AZ31 alloy was investigated. The results showed that the highest incorporation of nanoparticles occurs at a current density of 100 mA/cm(2) during 10 min while at higher current densities or treatment durations, the eruption of molten oxide prevents the embedding of nanoparticles inside the coating. The high incorporation of nanoparticles increased the homogeneity and compaction of the coating which caused the highest corrosion and wear resistance.