Wear and Electrochemical Corrosion Behavior of Biomedical Ti–25Nb–3Mo–3Zr–2Sn Alloy in Simulated Physiological Solutions

Abstract

The wear and electrochemical corrosion behavior of the biomedical Ti–25Nb–3Mo–3Zr–2Sn (TLM) titanium alloy was investigated in various simulated physiological solutions. Different simulated physiological solutions comprised phosphate-buffered solution (PBS), PBS with bovine serum albumin (PBS+BSA), and PBS with hyaluronic acid (PBS+HA) were employed. A potentiostat and a reciprocating friction and wear tester were used to study the wear and corrosion behavior of the TLM alloy. The influence of the chemical composition of the simulated solutions on the tribo-electrochemical behavior was considered by potentiodynamic studies under reciprocating friction and wear conditions. It was found that the corrosion tendency of the TLM alloy was the most obvious in PBS+HA under static corrosion condition, while it was just opposite with wear. Compared with static corrosion, the corrosion resistance of the TLM alloy was decreased with sliding conditions. The values of i corr were two orders of magnitude higher than those at static corrosion. This phenomenon shows that the wear accelerated corrosion. Under coexisting condition of both electrochemical corrosion and wear, the wear rate of the TLM alloy mutually influenced by both factors will be accelerated. Plastic grooves and deformation were observed on the worn surfaces of the TLM alloy by scanning electron microscopy (SEM). Through the observation of SEM, the tribological mechanism was a typical corrosive wear, and the main wear mechanisms were abrasive with adhesive wear under the interaction between corrosion and wear. The XPS results show that the passive films include the TiO2, ZrO2, Nb2O5, Mo2O5, and Sn2O3.