The effects of different hot compression conditions and multiple heat treatments on the microstructure evolution of TC4-DT titanium alloy were analyzed. The results reveal that the primary α phase in the microstructure is gradually decreased

and the acicular martensite precipitated by water quenching is gradually increased with increasing in temperature of hot compression deformation. The interweaving of the basketweave microstructure in the alloy is more uniform and compact after triple heat treatment at relatively low deformation temperatures of 920 ℃ and 950 ℃. The precipitated acicular α phase is more finely as the strain rate increases at the same time. The duplex microstructure is formed at 920 ℃

and the basketweave microstructure is formed at both 940 ℃ and 960 ℃

while acicular α-phase interlaced the basketweave microstructure is better in the latter. When the double temperature is less than 900 ℃

the acicular α-phase precipitated is relatively slender and grows with increasing in temperature. However

the basketweave microstructure is not uniform through observing the overall morphology. It is found that at 920 ℃

the basketweave microstructure formed in the microstructure is more compact

and the more finer acicular α phases are intertwined therein in the microstructure.