Effect of Thermal Oxidation Duration on Microstructure and Properties of Ti6Al4V Alloy

Thermal oxidation (TO) treatments were conducted on Ti6Al4V alloy at 973 K for 10, 20, 30, 40 and 50 h. The microstructural characteristics of the TO layers were analyzed using X-ray diffraction (XRD), glow discharge optical emission spectrometer (GDOES) and scanning electron microscope (SEM). The effect of TO duration on microstructure and properties of Ti6Al4V were investigated by microhardness tester, friction-wear testing machine and electrochemical workstation. The results show that the obtained TO layers are uniform and continuous. Prolonging the TO duration is beneficial to thickening the TO layers. The TO treatment significantly improves surface hardness, and enhances wear resistance as well as anti-corrosion property of the Ti6Al4V alloy. However, the improvements are not linearly correlated with the TO duration. The TO layer produced by 973 K/30 h process exhibits more promising characteristics than other TO layers, taking account of thickness value, surface hardness, wear resistance and anti-corrosion property,