Hydroxyapatite coating of AZ31 magnesium alloy by a solution treatment and its corrosion behavior in NaCl solution

► Magnesium alloys as bioabsorbable materials. ► AZ31 alloy and pure Mg are treated in a weak alkaline Ca-EDTA aqueous solution. ► Highly crystalline hydroxyapatite coatings can be directly formed on both the substrates. ► Microstructure of the HAp coatings depends on the kind of substrate. ► The HAp-coated AZ31 alloy shows high corrosion resistance and good adhesiveness.