Modification of the titanium oxide morphology and composition by a combined chemical-electrochemical treatment on cp Ti

Abstract

A combined chemical-electrochemical oxidation method to obtain porous bioactive TiO 2 films on titanium is reported. In this case, a titanium chemical pre-etching followed by the micro-arc oxidation (MAO) treatment is proposed and optimized, to obtain a high-roughness and porous surface which benefits the titanium/bone integration. The MAO treatment at various rates (different current densities) allowed to define the influence of the oxide growth rate on the surface morphology and to design the best features for each case. Titanium samples were pre-etched using a 2% HF solution as a function of the etching time, and then anodized by the MAO treatment in a 0.5 M H 3PO 4 solution at current densities in the 10 to 90 mA.cm -2 range. High porosity (0.5 to 1 μm-diameter pores) and higher phosphorous content for TiO 2 films were achieved by first etching the Ti sample for 180 seconds in the HF solution, and then applying current densities in the 80 to 90 mA.cm -2 range for the micro-arc oxidation process.