Enhancing corrosion and wear resistance of Mg coating on titanium implants by micro-arc oxidation and heat treatment

Abstract

Mg coating is one of the viable options for Ti to enhance its bioactivity. However, the rapid corrosion of Mg coating in physiological conditions has delayed their introduction for therapeutic applications to date. In this study, a ceramic layer between Ti substrate and Mg coating was prepared and heat treatment was also carried out to improve the corrosion resistance of the Mg coating. The in vitro test revealed that the ceramics layer decreased the galvanic corrosion between the Mg coatings and substrate, improved the corrosion resistance and wear properties. Furthermore, the post-heat treatment of Mg coating on Ti had a significant effect on the surface morphology and microstructure of the coating. The heat-treated Mg coatings on Ti at 400 °C for 10 min substrates showed an improved corrosion resistance compared with the untreated substrate. The heat treatment significantly influenced the hardness, adhesion, friction coefficient, and wear resistance of the coating.