Evaluation of electrochemical properties of thermally oxidised Ti–6Al–4V for bioimplant application

Abstract

The present study concerns development of a thin and adherent oxide film on the surface of Ti–6Al–4V by thermal oxidation and evaluation of its electrochemical properties for the possibility of its end use as coating on bio-implant. Thermal oxidation was carried out over a range of temperatures from 400 to 600°C and time ranging from 25 to 60 h. Surface oxidation leads to formation of an adherent oxide scale consisting of different oxides of titanium, mainly Ti 2 O 3 and TiO 2 (both rutile and anatase). A significant improvement in corrosion resistance (both corrosion potential and critical potential for pit formation) of the oxide layer was achieved by thermal oxidation. The oxidised surface showed a better wettability and pitting corrosion resistance against simulated body fluid.