Misorientation-dependent twinning induced hardening and texture evolution of TWIP steel sheet in plastic deformation process

Licensee MDPI, Basel, Switzerland. The quantitative contribution of twinning to hardening behavior and its effect on crystal orientation need to be explored in greater depth for design and forming of twinning-induced-plasticity (TWIP) steel products. To address this issue, the characteristics of twinning formation in the plastic deformation of Fe-30Mn-3Si-2Al TWIP steel are investigated in terms of intergranular misorientation distribution using electron back-scattering diffraction (EBSD), which reveals that most deformation twins adhere to the high-angle grain boundaries (HAGBs) of the face-center-cube (FCC) type TWIP steel. Texture measurements are conducted to show a stable volume fraction of major components including Goss, S and A orientations, while Copper shifts towards Brass orientation. A crystal plasticity finite element (CPFE) model based on virtual polycrystalline microstructure adopting representative volume element (RVE) is employed to simulate the deformation to reveal the correlation between misorientation-dependent twinning and hardening behavior of TWIP steel. The results demonstrate that the proportion of twinning hardening to overall hardening is larger than slip hardening. The stability of texture evolution is simulated to predict the anisotropy of TWIP steel. This research substantiates the twinning induced hardening and texture evolution in deformation of TWIP steel and thus is essential for accurate prediction of the mechanical behaviors.