Modeling Microstructural Development During Hot Working of Ni-Based Superalloy Alloy 680

In this work, dynamic recrystallizationDynamic recrystallization kinetics for a nickel alloyNickel alloys are characterized during hot deformation. Gleeble compression testing within a temperature range from 927 to 1149 °C is employed to replicate typical forgingForging conditions with strain rateStrain rate varying from 0.1 to 10 s−1. Microstructural and flow stress results were analyzed via the Johnson-Mehl-Avrami-Kolmogorov (JMAKJMAK) model that describes the mechanisms triggering recrystallizationRecrystallization during forgingForging operations. This model considers the significant variables of hot deformation such as temperature, strain, strain rateStrain rate, and initial structure. The developed model illustrates the dynamic recrystallizationDynamic recrystallization fraction and dynamically recrystallized grainRecrystallized grains diameter within defined temperature ranges based on the JMAKJMAK configuration. Results indicate that deformation above 1093 °C yields high dynamic recrystallizationDynamic recrystallization. Conversely, at lower temperatures, grain structure is highly dependent on strain and strain rateStrain rate. Validation tests coupling Gleeble compression testsCompression test and FE modeling comparisons covering the forgingForging conditions are included in this study.