Temperature dependence of intersection reactions of ε martensite plates in an Fe–30Mn–4Si–2Al TRIP/TWIP steel

Highlights: ► We focus on the microstructure at the intersections of two different habit-plane variant plates of strain-induced HCP martensite in TRIP/TWIP steel. ► In this study, the deformation temperature dependence of intersection structure has been investigated by electron backscatter diffraction, emphasizing the thermodynamic aspect. ► It is found that the intersection ε (which is reported by Yang and Wayman) and ε twins increase with decreasing temperature and the intersection γ forms even at as low temperature as −100 °C. -- Abstract: Temperature dependence of intersection structures in grains oriented to near 〈1 0 1〉 of a polycrystalline austenitic Fe–30Mn–4Si–2Al steel has been investigated by electron backscatter diffraction (EBSD). By the pole figure and misorientation angle analysis, it is found that the intersection ε (which is reported by Yang and Wayman) and ε twins increase with decreasing temperature and the intersection γ forms even at as low temperature as −100 °C. The variety of the intersection products can be interpreted by thermodynamic stability of ε phase