Corrosion Behavior of a New Ti–3Mo Alloy in Simulated Body Fluid for Biomedical Applications

Abstract

Ti–3Mo alloy was elaborated from Ti and Mo in a standard light-arc furnace, under controlled argon atmosphere. XRD pattern as cast binary shows a mixture of Ti, Ti–Mo and Mo 9Ti4 phases. Scanning electron microscopy, energy dispersive X-ray spectrometry analysis and optic microscope were used to characterize the binary surface. The Ti–3Mo alloy corrosion behavior was studied by chronoamperometry, electrochemical impedance spectroscopy (EIS) and Mott–Schottky techniques. The aim of the present work is to study the effects of the passivation of the oxide films developed at 1.5V versus saturated calomel electrode in 1 N H3PO4 for different anodization times (15, 30, 45, 60, 180 and 300 min) and their conductive properties in simulated body fluid solution. The anodization of the binary sample during 30 min led to the formation of n-type semiconductor which presents a charge carrier density of 1.30 × 1020 m−3. The obtained EIS data fitting with an appropriate equivalent circuit suggests that the passive film consists of two layers present on the alloy in the range of 15–300 min for anodization. All these electrochemical results suggest that the Ti–3Mo alloy is a promising material for biomedical devices, since electrochemical stability and no toxicity are directly associated with biocompatibility. Although the studied binary is less rich in molybdenum than those cited in the literature, it nevertheless performed better than those richer in molybdenum.