Effects of Alkali and Heat Treatment on Apatite Forming Ability of a Micro-Arc Oxidized Ti6Al4V Alloy

Abstract

To further improve the bioactivity of Ti6Al4V alloy and to accelerate bone growth, the porous TiO2 coating containing calcium and phosphate prepared on Ti6Al4V alloy substrate using micro-arc oxidation (MAO) technique was treated in 5M NaOH aqueous solution at 60 °C for 24 h and followed by a heat treatment at 400 °C for 1 hour (termed as MAONH). The experimental results showed that Ca2+ and P5+ easily precipitated on the MAONH coating and formed a thicker apatite film. The reason could be ascribed to hydrolysis of CaTiO3, which resulted in appearance of large numbers of Ca2+ and OH- ions within coating.