Improvements of the surface properties of Ti6Al4V by plasma based ion implantation at high temperatures

Ti6Al4V is a titanium alloy that has many applications in aerospace industry due to its good mechanical and corrosion properties, but its poor tribological characteristics can restrict the use of this material. In order to modify its surface properties, nitrogen PBII treatments were performed. Here, an auxiliary heating system was used to reach the required high temperatures, which can improve the nitrogen diffusion in the titanium alloy. As a consequence, the modified thickness could be increased substantially. After nitrogen PBII experiments, the Ti6Al4V alloy surface properties were evaluated by potentiodynamic polarization, electrochemical impedance spectroscopy, nanoindentation and pin-on-disk tests. The morphology of the surface after corrosion tests was obtained by SEM. The surface properties of the Ti6Al4V alloy were improved after PBII, showing better performance in corrosion, mechanical and tribological tests.