Elemental segregation, microstructure, and mechanical properties of TMCP-treated high-manganese wear-resistant steel

The elemental segregation, microstructure, and mechanical properties of thermo-mechanical control process (TMCP) treated high-manganese wear-resistant steel (HMWS) were experimentally investigated. Firstly, the initial elemental segregation in the continuous casting slab of HMWS was characterized using the original position analysis. The results showed that the elemental segregation predominantly occurred near the quarter and the center regions of the slab. The homogenization of manganese (Mn) in the slab was not as obvious as that of other elements after the heating process. Subsequently, a series of hot-rolling tests were carried out on HMWS slab samples under different TMCP conditions, and the elemental segregation and microstructure of the TMCP-treated HMWS were investigated by microscopic analysis methods. The findings demonstrated that the segregations of carbon and silicon were effectively eliminated after the TMCP treatment, while Mn segregation presented a band-shaped arrangement and could be reduced at lower finishing rolling temperatures. The matrix phase of HMWS remained austenite regardless of the TMCP conditions, and the average size of austenite grains increased with the increasing finishing rolling temperature. Carbide particles were observed to form within austenite grains and even along grain boundaries at higher coiling temperatures. Finally, the mechanical tests were performed on the TMCP-treated HMWS at room temperature. The mechanical properties including tensile stress, yield stress, Charpy impact energy, and microhardness were discussed considering the effects of Mn segregation band, microstructure, and carbide precipitation.