In order to improve the wear resistance of titanium alloy drill pipe,the combined strengthening method of surface mechanical grinding treatment and carburizing was used on the surface of low-cost powder metallurgical Ti-Al-Fe-Mo alloy.The microstructure evolution and microhardness distribution of the surface treated with different surface grinding passes and carburization were investigated.The reciprocation sliding wear tests were carried out on the titanium alloy samples treated by different grinding passes and carburization using silicon nitride ball as friction pair.The effects of surface strengthening layer of titanium alloy on its wear loss,friction coefficient and the microstructure of worn track were studied.The results show that the gradient nanocrystalline structure is formed on the surface of powder metallurgical titanium alloy by surface mechanical grinding treatment,and the carburizing depth and uniformity of titanium alloy is significantly improved after surface mechanical grinding treatment.Compared with the surface carburized titanium alloy,the wear loss of the titanium alloy treated by the combined strengthening of surface mechanical grinding treatment and carburizing is reduced by 58%.Fatigue wear,adhesion wear,oxidation wear and some abrasive wear are the main wear mechanisms of surface combined strengthening titanium alloy.