Mechanical behavior of plasma-sprayed pure and reinforced hydroxyapatite coatings on Ti6Al4V alloy

Hydroxyapatite coatings with secondary reinforcement have attracted the attention of the researchers of concerned field. Reinforcement like alumina and titania are used to make the HA coatings more wear resistant. It has been reported in the existing published literature that wear and corrosion are the main cause of the bio-implant failure. This paper deals with the abrasive wear and electrochemical corrosion behavior of as-sprayed and heat-treated pure and 10 wt% 80Al2O3-TiO2-reinforced hydroxyapatite coatings successfully deposited by atmospheric plasma spray technique. Simulated body fluid (SBF) was prepared in laboratory to be used in electrochemical corrosion testing. Samples were dipped in SBF before abrasive wear testing. The coatings were characterized by XRD and SEM-EDAX analysis. Post-coating heat treatment was carried out at 700 and 800 °C. It has been found that post-coating heat treatment at 700 °C has favorable impact on both corrosion and wear resistance of coatings along with hardness and crystallinity of the coatings.