The effects of aging temperature and aging time on microstructure evolution and mechanical properties of Ti-6Al-2.5V-1.5Fe-0.15 O alloy prepared by high vacuum non consumable arc furnace were investigated after solid solution treatment and air cooling. The results reveal that with a lower aging temperature

nuclear energy ofα is low

leading to diffusion diffuculy of elements

so α nucleation needs the aid of dispersed ω phase

which results in the small and dispersed needle-like α phase. With increasing in aging temperature

driven force of nucleation and growth of α phase are increased

resulting in easy to be grown up of aging phase. With increasing in aging time

the aging α phase is coarsened

and the aging region is increased. After aging treatment

α phase is responsible for the increase of alloy strength. As the aging time increase

the yield strength and the peak strength are decreased

while the fracture strain is increased.