Effects of sliding velocity on tribo-oxides and wear behavior of Ti-6Al-4V alloy

Dry sliding wear tests were performed for Ti-6Al-4V alloy on a pin-on-disc wear tester. The wear behavior of Ti-6Al-4V alloy at sliding velocities of 0.5-4 m/s was studied and the tribo-oxides and their function were explored. Ti-6Al-4V alloy presented a marked variation of wear rate as a function of velocity. With the rise and fall of wear rate, Ti-6Al-4V alloy underwent the transitions of wear mechanisms from the combination of delamination wear and oxidative wear at lower speeds to delamination wear at 2.68 m/s, and then to oxidative wear at 4 m/s. These phenomena were attributed to the appearance and disappearance of tribo-oxides. In spite of trace or a small amount, tribo-oxides would change the wear behavior, and even wear mechanism. (C) 2015 Elsevier Ltd. All rights reserved.