Abstract:The initial equiaxed Ti-55531 alloy has been carried out the isothermal compression deformation with 0.01, 0.1 and 1 s~(-1) above the phase transformation point, and heat treatment at 750 ℃×5 min/AC. The scanning electron microscope and transmission electron microscope technologies were used to investigate the static recrystallization of deformed α and matrix β phases during subsequent heat treatment. The results show that the content of residual equiaxed α phase increase with the increase of strain rate. The spheroidization behavior of elongated α phase in the deformed alloy occurs after heat treatment. Meanwhile, the dislocation storage energy within β phase is large at the end of the elongated α phase with relative high strength, which facilitates the β recrystallization and nucleation and improved the local high-density secondary α-phase precipitation during air cooling.