The Ti811 titanium alloy sheet was subjected to multi-pass rolling and then annealed.The microstructure

fracture structure and mechanical properties of the rolled alloy were analyzed by optical microscope

scanning electron microscope and tensile testing.The results reveal that the microstructure of the rolled titanium alloy is mainly composed of elongatedβ-phase grains and coarse lath-likeα-phase grains.Annealing after rolling can promote the equiaxification ofα-phase grains andβ-phase grains.Meanwhile

annealing treatment also promotes the conversion ofαphase grains intoβphase grains

and with increasing in the annealing temperature

the conversion ratio is increased.Annealing treatment is beneficial to reduce the difference of the anisotropic tensile strength of the rolled titanium alloy.The room temperature comprehensive mechanical properties of the samples annealed at 900℃ present desirable

where the tensile strength of LD and TD direction are 947.4MPa and 924.7MPa and the elongations reach 11.6%and 9.4%

respectively.The fracture modes of the two samples annealed at900℃are characterized by ductile fracture.