First-Principles Study on Stacking Fault Energy of γ-Fe–Mn Alloys

Abstract

The ground state properties and generalized stacking fault energy (GSFE) of γ-Fe–Mn alloys with different Mn concentrations are calculated by ab initio simulation. The calculation results of intrinsic stacking fault energies (ISFE) show that Mn atoms have a significant short-range effect on the ISFE; the parabolic relationship between ISFE and Mn atom concentration of antiferromagnetic (AFM) Fe–Mn alloys is explained by the cohesive energy and density of states (DOS) of the alloys. AFM increases ISFE of γ-Fe–Mn alloys compared to non-magnetic (NM). The importance of considering magnetic interactions in ISFE of γ-Fe–Mn alloys is proven and it is very significant to study the deformation behavior of medium manganese steel. We have investigated the stacking fault energy of antiferromagnetic γ-Fe–Mn alloys and proved that that magnetism has an important influence on stacking fault energy in γ-Fe–Mn alloys. We have confirmed the parabolic relationship between ISFE and Mn atom concentration of AFM-Fe–Mn alloys can be explained by the cohesive energy and DOS of the alloys.