采用Gleeble3500型热模拟试验机对粉末热等静压制备的Ti6Al4V合金进行不同温度和应变速率下的高温压缩试验，建立了可描述合金在两相区的压缩行为的本构方程，对合金热加工过程中的加工硬化、动态软化参数和动态再结晶动力学模型进行求解，并构建了合金在两相区的流变应力模型。结果表明：所制备的Ti6Al4V合金组织由α相和β相组成，呈典型的网格结构，网格由细小的等轴α相形成，网格内部为相互交错的层片状α相，β相分布在α相边界处；所建立的Ti6Al4V合金在α+β两相区的流变应力模型的计算结果与试验结果吻合较好，该流变应力模型具有较高的准确性。

High-temperature compression tests were carried out on Ti6Al4V alloy prepared by powder hot isostatic pressing with a Gleeble3500 thermal simulator at different temperatures and strain rates. A constitutive equation describing the compression behavior of the alloy in two-phase region was established. The hardening, dynamic softening parameters, and dynamic recrystallization kinetics models of the alloy during hot working were solved. The flow stress model of the alloy in two-phase region was constructed. The results show that the microstructure of the prepared Ti6Al4V alloy was composed of α phase and β phase and presented a typical grid structure. The grids were formed by the small equiaxed α phase with interleaved lamellar α phase inside, and β phase was distributed at the boundary of α phase. The results calculated by flow stress model of Ti6Al4V alloy in α+β two-phase region was in good agreement with the experimental results, and the flow stress model had high accuracy.