New Method for the Production of Medium-Mn Steel with Micro-segregation Bands Induced by Sub-rapid Solidification

Medium-Mn steelMedium-Mn steel has important applications in the lightweight automotive industry due to its excellent comprehensive mechanical propertiesMechanical properties. However, the existence of cumbersome production steps, high energy consumption, and severe macro-segregation seriously limits its industrial development. Hence, this study proposed a green-short method for producing medium-Mn steelMedium-Mn steel with micro-segregation bands using sub-rapid solidificationSub-rapid solidification technology. Exclusive components were designed, and OM, SEMScattering electron microscopy (SEM), EPMA, and EBSD techniques were used to characterize the microstructure distribution, grain orientation, and elemental micro-segregation of the as-cast strips. The phase transformation behavior and formation mechanism of Mn micro-segregationMn micro-segregation during the sub-rapid solidificationSub-rapid solidification process were deeply discussed. This work innovatively utilized the sub-rapid solidificationSub-rapid solidification characteristics to effectively avoid the macro-segregation problem of Mn, and cleverly transformed it into micro-segregation bands that were beneficial for mechanical propertiesMechanical properties. Furthermore, the design of short process provides valuable idea for the industrial production and application of medium-Mn steelsMedium-Mn steel.