Improvement in Surface Properties of Ti6Al4V Alloy by ZrN Thin Film

Abstract

Ti6Al4V alloy is attracting attention as a biomaterial due to its excellent mechanical properties, corrosion resistance and super plasticity. However; this alloy contains aluminium and vanadium liable to do serious harm to human bodies. For overcoming surface originated problems, various surface modification techniques have been used on metallic implants. In this study cathodic arc PVD was used to produce ZrN coating with different substrate bias voltage at 20mttor nitrogen gas pressure. Corrosion resistance of Ti6Al4V and ZrN coated Ti6Al4V were investigated by an electrochemical test, at 37°C in normal saline solution. Tafel extrapolation method was used for calculating corrosion rate. ICP-AES studies were carried out to determine amount of ions leached out from samples when kept immersed in normal saline solution. The surface morphology was carried out by XRD. The ZrN coated samples showed variation in the corrosion resistance with varying voltage and the sample coated at-200V showed an optimum corrosion resistance.