以某型航空发动机 GH4169 合金盘锻件为研究对象，针对晶粒尺寸及其均匀性调控难题，开展了锻造全过程晶粒尺寸演变规律的仿真研究。 建立了基于应变补偿的 Arrhenius 宏观流动应力本构模型，以及考虑 δ 相影响的动态再结晶与晶粒长大模型。 通过全过程几何与晶粒尺寸数据的遗传关系，建立了全过程宏微观有限元模型，以综合预测变形与晶粒尺寸演变，模拟揭示了全流程(锻粗-加热-预锻-加热-终锻)晶粒尺寸的分布及演变规律。 结果表明，锻粗与预锻通过局部不均匀大变形实现原始组织初步细化，但导致晶粒尺寸不均；中间加热利用大、小晶粒长大速度差异，使晶粒尺寸趋于均匀化；终锻在低速、等温条件下促使绝大部分区域发生充分动态再结晶，实现整体晶粒显著细化，平均晶粒度达 ASTM 9.0~9.5 级，仅在与模具接触的局部小变形区残留约 ASTM 7.5 级粗大晶粒。

Focusing on the forging process of an aeroengine GH4169 alloy disc component and addressing the challengesassociated with controlling grain size and uniformity, a simulation study was conducted on grain size evolution throughoutthe entire forging process. First, a strain-compensated Arrhenius constitutive model for describing the macroscopic flowstress and a dynamic recrystallization and grain growth model considering the influence of the δ phase were established.Second, considering the inheritance relationship of geometric and grain size data throughout the multistage forging process,a macromicro coupled finite element model was developed to comprehensively predict deformation and grain sizeevolution. Finally, the simulations reveal the grain size distribution and evolution throughout the entire process(upsetting-heating-preforging-heating-final forging). Upsetting and preforging achieve initial refinement of the originalmicrostructure through localized, nonuniform large deformation but result in an uneven grain size distribution. Intermediateheating processes, utilizing the difference in growth rates between large and small grains, promote grain sizehomogenization. During the final forging stage, under low-speed, near-isothermal conditions, sufficient dynamicrecrystallization is induced in the vast majority of the component, ultimately achieving significant overall grain refinementto an average grain size of ASTM 9.0~9.5. Only localized small deformation zones in contact with the die retain coarsergrains of approximately ASTM 7.5.