Corrosion behavior and biocompatibility of hydroxyapatite/magnesium phosphate/zinc phosphate composite coating deposited on AZ31 alloy

In this study, magnesium phosphate (Mg-3(PO4)(2)) and zinc phosphate (Zn-3(PO4)(2)) doped hydroxyapatite (HA, Cam(PO4)(6)(OH)(2)) composite coating was successfully deposited onto AZ31 alloy (0.002% Cu, 0.81% Zn, 0.37% Mn, 2.84% Al and balance Mg) by electrodeposition method. Electrochemical tests and degradation tests were conducted to study the corrosion behavior of hydroxyapatite/magnesium phosphate/zinc phosphate (HMZ) coated AZ31 alloy. Cell culture studies and hemolysis tests were performed to study the biocompatibility of HMZ coated AZ31 alloy. The results of Vickers microhardness proved that HMZ exhibited the highest mechanical strength. The results manifested that the corrosion resistance, the dissolution of Mg and Zn ions in HMZ composite coated AZ31 alloy and the biocompatibility of HMZ coated AZ31 alloy was greatly improved compared with magnesium phosphate/hydroxyapatite (HM) coated, zinc phosphate/hydroxyapatite (HZ) coated and hydroxyapatite (HA) coated samples. (C) 2017 Elsevier B.V. All rights reserved.