Study of Tribocorrosion Behaviour of Ti–25nb–3zr–2sn–3mo Alloy Induction Nitride Layer in a Simulated Body Fluidsolution

Abstract

Ti–25Nb–3Zr–2Sn–3Mo (TLM) alloy has been used in the field of orthopaedics because of its excellent biocompatibility. However, the poor tribological performance induced by the low shear strength limits the applicability of the TLM alloy. The present study shows that the induction nitriding technology can improve the TLM alloy’s tribocorrosion properties in simulated body fluids (SBF). After induction nitriding, a gradient nitriding layer with a thickness of about 30 μm on the surface of the TLM alloy is obtained, consisting of TiN layer on the surface and granular diffusion zone on the subsurface. Triborrosion behaviour is characterized by a reciprocating sliding wear tester connected to an electrochemical workstation with different electrochemical conditions in SBF. The results of electrochemical studies indicate a substantial enhancement of tribocorrosion resistance in TLM alloy treated by induction nitriding, attributed to the compact nitride layer with high hardness and corrosion resistance on the surface and the coordinated deformation of granular diffusion layer on the subsurface.

Keywords: TLM alloy, Induction nitriding, Gradient structure, Tribocorrosion, Synergistic effect.