Fabrication of hydroxyapatite/stearic acid composite coating and corrosion behavior of coated magnesium alloy

Magnesium alloys have attracted concerns as potential implanted biomaterials. This work utilized hydroxyapatite (HA) and stearic acid (SA) to potentially improve the clinical application of magnesium alloys by using the combination method of electrodeposition and solution method. A composite coating (SAHA) was developed on the substrate surface from the modification of HA coating by SA. It was found that the composite coating was porous, which may provide abundant sites for the growth of osseous tissue. Stearic acid was absorbed on the surface of HA coating through electrostatic attraction. The effects of coatings on corrosion behavior of magnesium alloys were also investigated. The results indicated that the composite coating could provide effective protection and enhance corrosion resistance for magnesium alloy. ► A combination method composed of electrodeposition and solution method was used. ► A composite coating was firstly prepared through physical adsorption on substrate. ► The composite coating obviously enhanced corrosion resistance of the substrate. ► The composite coating may improve application for magnesium alloy as biomaterial.