Microstructural evolution of dynamic recrystallization in hot-compressed nickel-based Superalloys: Optimization of DRX kinetics, and multiscale FEM coupled simulation

Dynamic recrystallization (DRX) is a key softening mechanism during the high-temperature thermomechanical processing of nickel-based superalloys, profoundly affecting grain refinement, texture evolution, and overall mechanical properties. In this study, hot compression tests were conducted on a newly developed nickel-based superalloy within the temperature range of 1070–1110 °C and strain rates of 0.001–1 s -1 . The true stress–strain curves were corrected for friction and adiabatic heating effects. Based on these corrected data, both a constitutive equation and an Avrami-type kinetics model were established. To more accurately capture the DRX process, the kinetic model was improved into a new form. The improve model is described using a quadratic function, dividing the DRX process into distinct stages, including nucleation, active growth, and gradual saturation, thereby capturing the characteristic “slow–fast–slow” evolution. Correlation coefficient–based comparative analysis indicated that the improve model showed a higher correlation with the experimental data than the traditional Avrami model. Finally, the improve model was implemented into Deform-3D finite element simulations, yielding predictions highly consistent with observed microstructural evolution. The proposed framework provides valuable guidance for the processing design and performance optimization of advanced nickel-based superalloys.