The hot deformation behavior and microstructure evolution of Ti60 alloy with lamellar starting microstructure were investigated through hot compression test in the temperature range 970e1030 C with 20 C intervals, strain rate range 0.01e10 s1 and height reductions of 40%, 60% and 80%. On the basis of the flflow stress obtained as a function of the strain rate and deformation temperature, the constitutive equation was established. It was found that the hyperbolic sine law equation is more applicable than the exponential law equation since the relative standard deviation of ln_ε ln½sinhðasÞ plot is lower than ln_ε s plot, and the hot deformation activation energy is calculated to be 839 kJ/mol. The results also showed that the deformation mechanism mainly involves the lobularization of the a lath. As a thermal diffusion process, the strain rate plays a remarkable effect on the globularization. The fraction of globularized a lath increased with the increase of the strain rate. Meanwhile, the globularization is sensitive to the orientation. At lower strain, only local favorable orientation a lath occurred globularization. With the increase of the strain, more a lath became kinking and globularization. The optimum deformation parameter for the globularization is in the temperature rang 990e1010 C, strain rate 0.01 s1 and height reduction of 60%.
