Ti-6Al-4V alloy was prepared by compression molding+vacuum sintering process.The effects of sintering temperature on the relative density

microstructure

phase composition and hardness of the alloy were systematically investigated with the help of OM

SEM

EDS

XRD

hardness tester.The results show that when the sintering temperature is 1 035℃and 1 100℃

the microstructure of the alloy is composed of equiaxedαgrains and intergranularβphase.When the sintering temperature is 1 150℃

the microstructure presents bimorphic and contains equiaxedαgrains

lamellar alpha grains and a small amount of intergranular beta phase.At the sintering temperature of 1 200 ℃ and 1 300 ℃

the microstructure contains a large number of lamellar alpha grains and small short rod-shaped alpha grains.When the sintering temperature is above 1 100℃

vanadium is almost absent in theαphase in the sample.As the sintering temperature increases

the ambient gas is more likely to invade the sample to form interstitial solid solution.When the sintering temperature is 1 300 ℃

the oxygen content in the sample reaches 0.507%.With the increase of sintering temperature

the densification process of the sample is accelerated

and the relative density of Ti-6Al-4V alloy sintered reaches 97.878% at 1 300℃.Due to the ascension of densification and the increase of interstitial elements

the hardness of Ti-6Al-4V alloy is increased with the sintering temperature increasing.