Computer and physical modeling of multiple isothermal forging of EK61 superalloy

Abstract

Studies on the process of multiple isothermal forging of high-temperature nickel-based EK61 superalloy using computer simulation in the DEFORM-3D software package in a three-dimensional formulation and a comparison with experimental data were carried out. Based on the simulation results, it is shown that with each subsequent stage of forging, the maximum strain values become higher, and the strain differences in the central and peripheral regions become smaller. Such a strain distribution leads to the formation of a homogeneous ultrafine-grained (UFG) microstructure. The initial coarse-grained microstructure is gradually transformed into a fine-grained microduplex type microstructure at 0.77Tmelt and with a further decrease in the processing temperature to 0.73Tmelt, it is transformed into a submicroduplex type (γ + δ) UFG microstructure.