Corrosion behavior of TiN and TiN/Ti composite films on Ti6Al4V alloy in Hank’s solution

摘要

Surface films of TiN and TiN/Ti were deposited on Ti6Al4V alloy by arc ion plating (AIP). Open-circuit potential, potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) were employed to investigate the corrosion performance of TiN and TiN/Ti films in Hank’s simulated body fluid at 37 °C and pH 7.4. Scanning electron microscopy (SEM) was used to study the surface morphology of the corroded samples after the potentiodynamic polarization tests. The results show that the TiN and the TiN/Ti films can provide effective protection for the Ti6Al4V substrate in Hank’s fluid, and the TiN/Ti composite film showed a corrosion resistance superior to that of the TiN film. The outer TiN layer of the composite film mainly acted as an efficient barrier to corrosion during short-term experiments. In contrast to the bare Ti6Al4V, no pitting was observed on the surface of the TiN and TiN/Ti films deposited on the bare alloy after potentiodynamic polarization.