Microstructure and Mechanical Properties of Ti-Mo Alloys by Powder Metallurgy Process

Ti-(8~20)Mo alloys made from elemental powders were fabricated by a powder metallurgy technique. The effects of sintering temperature and Mo content on the microstructure and mechanical properties were studied. The results show that the Ti-Mo alloys with high-density and uniform microstructure can be produced in the sintering temperature range of 1400~1500℃. The lowest sintering temperature for densification gradually increases with the rise of Mo content. Ti-(8~16)Mo alloys exhibit typical widmanstatten structure, whereas the Ti-20Mo alloy consists of single equiaxed β grains. In the range of 8%~16% of Mo, increasing Mo content can decrease β grains in size, and correspondingly the α lamellars become less and thinner. The as-PMed Ti-(8~20)Mo alloys show good mechanical performance, and possess lower elastic modulus of 59~68 GPa. In comparison, the Ti-14Mo alloy sintered at 1450℃ exhibits superior mechanical properties with hardness of 35.7HRC, compressive strength of 2227 MPa, compression rate of 29.1%, and elastic modulus of 62.2 GPa.