Abstract:Ti-Al-Fe-Mo alloy was prepared by powder metallurgy method with titanium, aluminum, molybdenum and iron powders used as raw materials, and the alloy was used to fabricate valves for motorcycle engines. The microstructure as well as performance evolution of the alloy during the preparing process was investigated. The performances of motorcycle engines assembled with Ti valves were also tested. The results show that Ti-Al-Fe-Mo alloy prepared by powder metallurgy has excellent comprehensive performances with ultimate tensile strength 1232 MPa, yield strength 1186 MPa, elongation 6.5% and hardness 49 HRC. The fabricated valves after coating TiN can meet the requirement of on board tests of the motorcycle engine. Compared with assembling steel valves, power and torque of the motorcycle engines assembled with Ti valves are improved by about 12%, fuel consumption rate is reduced by 1% and the noise is also significantly lowered.