Adhesive strength and bioactivity of titania films prepared by micro-arc oxidation

Titanium dioxide films containing Ca and P on the surface of titanium were prepared by micro-arc oxidation. The effect of micro-arc voltage on the microstructure and adhesive strength of the films was studied, and the bioactivity of the films was also evaluated. The results show that titanium dioxide films obtained from micro-arc oxidation have porous structure and the films prepared at high voltage of 450 V can induce apatite to form on its surface after soaked in simulated body fluid(SBF) for 14 d. These films present good bioactivity. However, the films prepared at lower voltage have no bioactivity. Their adhesive strength reduces with the increase of the voltage, but it is higher than 31.4 MPa in the voltage of 250-450 V.