Wear and corrosion behaviour of Ti-13Nb-13Zr and Ti-6Al-4V alloys in simulated physiological solution

Abstract

Wear and corrosion behaviour of cold-rolled Ti-13Nb-13Zr alloy, with martensitic microstructure, and Ti-6Al-4V ELI alloy, in martensitic and two-phase (alpha + beta) microstructural conditions, was studied in a Ringer's solution. The wear experiments were performed at room temperature with a normal load of 40 N and sliding speeds 0.26. 0.5 and 1.0 m/s. The corrosion behaviour was studied at 37 degrees C using open circuit potential-time measurements and potentiodynamic polarization. It was found that Ti-13Nb-13Zr alloy has a substantially lower wear resistance than Ti-6Al-4V ELI alloy in both microstructural conditions. Surface damage extent increases with sliding speed increase and is always smallest for martensitic Ti-6Al-4V ELI alloy with highest hardness. Both alloys exhibit spontaneous passivity in Ringer's solution. Corrosion potential values are similar for all three materials. However, Ti-13Nb-13Zr and martensitic Ti-6Al-4V ELI alloys show improved corrosion resistance comparatively to Ti-6Al-4V ELI alloy with (alpha + beta) microstructure. Martensitic Ti-6Al-4V ELI alloy possesses the best combination of both corrosion and wear resistance, although its corrosion resistance is found to be slightly higher than that of the Ti-13Nb-13Zr alloy.