Strengthening Triggered by Deformation Twins in a Hot-Rolled High-Mn Steel: The Role of Stacking Fault Energy

In this study, the contribution of deformation twins to the strength of high-Mn steel was quantitatively evaluated through experiments and explained through stacking fault energy. X-ray diffraction was conducted to identify the phase and measure the broadening of diffraction peaks. The dislocation density was calculated using the modified Williamson-Hall model. No strain-induced martensitic transformation was found during the tensile test at room temperature. The contribution of initial dislocation to the yield strength was determined to be approximately 37.4% during the yielding stage, and the contribution of deformation twins was negligible. During plastic deformation, the contribution of deformation twins to the flow stress increased with increasing stress. The ultimate contribution of deformation twins was found to be equivalent to that of dislocation. It may be attributed to the favorable conditions provided by the appropriate stacking fault energy for the formation of deformation twins.