Investigation of surface properties and corrosion behavior of plasma sprayed HA/ZnO coatings prepared on AZ31 Mg alloy

Magnesium and its alloys have been introduced as innovative orthopedic implants due to their potential in serving lightweight, bio-active, degradable, and biocompatible properties. Mg and its alloys corrode rapidly in a biological environment and result in losing mechanical properties. However, to enhance corrosion resistance and mechanical properties, Mg alloy was plasma-sprayed with pure hydroxyapatite (HA) and HA reinforced Zinc Oxide (ZnO) powder at three levels (4, 8, and 12 wt%). Surface parameters such as microhardness, surface roughness, and wettability were examined. The electrochemical technique was used to study the corrosion behavior in Ringer's solution. The outcomes confirmed that with the rise in ZnO content in pure HA coatings, the surface properties as well as the corrosion resistance improved significantly. The contact angle of substrates under examination exhibits hydrophilic nature. Collectively, the findings of this study signify HA/ZnO reinforced coatings are a promising approach to improve surface properties and corrosion behavior of Mg alloys for future bone implant applications.