Influence of sodium silicate concentration on properties of micro arc oxidation coatings formed on AZ91HP magnesium alloys

► Sodium silicate can change the coating color. ► Silicate ions combine with magnesium and aluminum ions to develop anodic coatings. ► Sodium silicate competes with phytic acid for taking part in coating formation. ► Sodium silicate improves the corrosion resistance of MAO treated magnesium alloys.