Hot Deformation of AISI 4340 Steel From a Dynamic Material Modeling Perspective

This study presents numerical simulations of hot deformed AISI 4340 steel using Deform 3D, conducted at temperatures of 1000°C–1150°C and strain rates of 3–12 s −1 . Processing maps and constitutive modeling characterize deformation mechanisms and flow stress behavior. Dynamic recrystallization acts as the dominant softening mechanism. Flow stress increases with decreasing temperature at constant strain rates, peaking at ∼0.4 true strain. The stress exponent and activation energy are 7.5 and 458.25 kJ/mol, respectively. The model demonstrates high predictive accuracy with an R 2 of 0.997, average absolute relative error of 0.779, and Pearson’s value of 0.999. Processing maps reveal peak efficiency of 36% at 12 s −1 between 1000°C and 1010°C, indicating optimal processing conditions for AISI 4340 steel. These results are significant for designing large‐scale industrial forging processes of structural components.