Hydroxyapatite/titania composite bioactivity coating processed by the sol-gel method

A hydroxyapatite/titania composite material was coated onto a titanium (pure Ti) substrate by the sol-gel method. HA (hydroxyapatite) and TiO2 (titania) sols were made from precursors separately and mixed together. The mixed sol was coated onto the Ti substrate by a spin coating method. The coated samples were dried and heat-treated at certain temperature. The XRD data show that there is an improvement in crystallization and growth of the grain size as the temperature increases. The addition of TiO2 delayed the crystallization of HA and accelerated its decomposition. The composite HA coating has a porous structure. The addition of TiO2 also improved the corrosion resistance of the coating.