Abstract:A new triple melting method with hot extrusion process for GH4710 alloy ingots has been developed to overcome the difficulty in deformation of GH4710 alloy prepared by the casting and forging process. The as-extruded GH4710 alloy was analyzed through the isothermal compression experiment and metallographic analysis. The viscoelastic stress characteristics and dynamic recrystallization (DRX) behavior of the as-extruded GH4710 alloy were investigated during deformation at temperatures ranging from 1050 °C to 1120 °C and strain rates ranging from 0.01 s-1 to 5.00 s-1. The true stress-true strain curves, average grain size, and DRX volume fraction were also obtained under various deformation conditions. Prediction models for DRX volume fraction and grain size of the as-extruded GH4710 alloy were established using the statistical regression method. The model was implanted into the Derform-3D software, and numerical simulation of the microstructure evolution of GH4710 alloy was conducted. Firstly, the isothermal compression simulations were conducted using the finite element method to verify the accuracy of prediction model. Subsequently, the prediction model was applied to perform an optimization analysis of the forging process for a turbine disk with a diameter of 300 mm. Results show a strong correlation between the simulated results and the actual microstructure of the turbine disk forged through the optimal process parameters. The optimal process parameters are deformation temperature of 1100 °C and forging speed of 0.2 mm/s. This established DRX prediction model can serve as a fundamental reference for understanding the microstructural evolution during the hot deformation process of as-extruded GH4710 alloy.