Abstract: A single pass hot deformation experiment was carried out on 9Cr3W3Co alloy by using Gleeble-3800 thermal simulator at the temperature of 950-1150 ℃， the strain rate of 0.1-10 s^-1and the deformation of 70.9%. In order to better simulate the on-site process， the multi pass deformation process simulation simulation was carried out by using the scheme of the pass deformation from large to small and the pass deformation from small to large. The strain rate was 5.0 s^-1,and the total deformation amount was 70.9%. The deformation characteristics of dynamic recrystallization behavior of 9Cr3W3Co alloy used for steam turbine blades were studied， the stress-strain curve of the alloy was obtained， and the dynamic material model is used to construct the 3 D thermal processing diagram of the alloy under different deformation conditions. The results indicate that the stress-strain curve of 9Cr3W3Co alloy shows that the stress decreases with the increase of deformation temperature and increases with the increase of strain rate. In order to accurately describe the relationship between the three， the hyperbolic sine constitutive equation is established， and finally its thermal activation energy is 655.051 kJ/mol. Combined with the analysis of the results of microstructure evolution， it is concluded that the best hot working area of the alloy should be： deformation temperature 1050-1150 ℃， strain rate 0.1-1 s^-1. In the process of rapid forging deformation， the forging process of first large deformation and then small deformation is conducive to obtaining uniform grain size

Key words: 9Cr3W3Co, Constitutive Equation, 3D Thermal Processing Diagram, Dynamic Recrystallization

摘要： 利用 Gleeble-3800热力模拟机，在温度 950～1150 ℃，应变速率 0.1～10 s^-1，变形量为 70.9% 的条件下，对9Cr3W3Co合金进行了单道次热变形实验。为了更好地模拟现场过程，分别采用道次变形量由大到小以及道次变形量由小到大的方案，进行多道次变形过程模拟，应变速率为5.0 s^-1，总变形量为70.9%。研究了汽轮机叶片用9Cr3W3Co合金动态再结晶行为的变形特点，得到了合金的应力-应变曲线，并利用动态材料模型构建该合金在不同变形条件下的三维热加工图。结果表明，9Cr3W3Co合金的应力-应变曲线表现出应力随变形温度的升高而降低，随应变速率的增大而增大。为准确描述三者间的关系，建立了双曲正弦本构方程，最终得到其热激活能为655.051 kJ/mol，结合微观组织演变的结果分析，得出合金的最佳热加工区域应为：变形温度 1050～1150 ℃，应变速率0. 1～1 s^-1并且在快锻变形过程中，先大变形后小变形的锻造工艺有利于获得均匀的晶粒尺寸。

关键词: 9Cr3W3Co, 本构方程, 3D热加工图, 动态再结晶