Improving the wear resistance of Ti-6Al-4V/TiC composites through thermal oxidation (TO)

This study employed thermal oxidation (TO) treatment as a way of improving the wear resistance of Ti-6Al-4V/10 vol.% TIC composites (TMCs) - especially at high loading conditions. The study revealed the formation of a uniform oxide layer (2.6 +/- 0.35 mu m thick) supported by an oxygen diffused zone (31.2 +/- 11.6 mu m deep) on the composite's surface when thermal oxidation was carried out at 800 degrees C for 20 min. The dry sliding wear behaviour of the TO-treated and untreated TMCs was investigated using a ball-on-disk tribometer within a load range of 2-10 N. According to the experimental results, different wear behaviours were identified for TMCs and TO-TMCs as a function of applied load. The TO-treatment significantly reduced the wear rates of TMCs, especially at high loading conditions, due to the presence of a hard oxide layer and diffused zone that not only enhanced the load-bearing capacity of the TMCs, but also hindered the abrasive effect of the TiC particles and the extensive plastic deformation of Ti matrix. (C) 2010 Elsevier B.V. All rights reserved.