Improvement of Wear Resistance of Titanium by the Dispersion of Carbides

Abstract

Titanium alloys have various excellent characteristics, such as good corrosion-resistance and high specific strength. However, they have not been applied to the sliding parts of machine because of the lack of wear resistance.
In this study, in order to improve the wear resistance of titanium, the effects of the kind and quantity of carbide on wear resistance of a carbide dispersed titanium alloy have been investigated using the Plasma Transferred Arc (PTA) process and Ar arc melting.
Results obtained through this study are :
(1)[Ti-6Al-4V W₂C] and [Ti-6Al-4V + Cr₃C₂] alloys showed wear resistance superior to a Co-based alloy ( Stellite) under the sliding wear test. It was also confirmed that they scarcely wore opposing steel.
(2) The excellent wear resistance of these carbide dispersed alloys is attributed to the microstructure which consists of fine TiC particles dispersed uniformly and a tough and hard matrix of the βTi phase formed by the addition of β-stabilizer, that is, W or Cr during the PTA process and Ar arc melting.
Consequently, wear resistance of the alloys containing the carbides (NbC, TiC) which do not transform the titanium matrix into the βTi phase is not improved.