Effect of air pressure on thermal oxidation and wear behaviour of Ti6Al4V alloy

In this study, effect of low air pressure on the thermal oxidation and wear behaviour of Ti6Al4V alloy was examined. Oxidation at 750 degrees C for 2 h under 1.0 x 10-5 atm created a thinner oxide scale but maintained an equivalent oxygen diffusion zone. It provided equivalent surface hardness, but, improved oxide adhesion, and wear resistance compared to oxidation at the same temperature for 2 h under 1 atm. The alloy treated under low air pressure showed wear resistance two orders of magnitude higher than oxidation performed at atmospheric pressure. Both oxidised alloys significantly outperformed untreated Ti6Al4V in sliding wear tests conducted under a 3 N load. Low air pressure oxidation offers better wear resistance while maintaining surface integrity.