Formation of flower-like structures for optimizing the corrosion resistance of Mg alloy

A flower-like structure responsible for improving the corrosion resistance of AZ31 Mg alloy was successfully obtained by plasma electrolytic oxidation (PEO) followed by post treatment. The PEO coatings samples obtained in electrolytes with/without ZrO2 underwent to subsequent immersion treatment in 8-hydroxyquinolate (8-HQ) solution for 72 h. It was observed that the formation of flower-like bis (8-hydroxyquinoline) magnesium inside the micro-pores of PEO coating was triggered when the coating was formed from electrolyte without ZrO2. As a result, a significant improvement in the corrosion resistance of Mg alloy was obtained.