Effect of Warm to Hot Rolling on Microstructure, Texture and Mechanical Properties of an Advanced Medium-Mn Steel

The deformation microstructures and mechanical properties were studied in a medium-Mn austenitic steel subjected to warm-to-hot rolling. During warm rolling at temperatures of T < 1073 K the structural changes were controlled by dynamic and static recovery leading to a pancaked work-hardened microstructure, during hot rolling at T ≥ 1073 K—by discontinuous dynamic and post-dynamic recrystallization resulting in equiaxed grains. The grain size decreased while the dislocation density increased with a decrease in rolling temperature. A decrease in rolling temperature enhanced the texture development, which consisted of relatively strong Brass, S and P components. The Brass component exhibited the strongest temperature dependence. A decrease in rolling temperature resulted in significant strengthening of the steel. The yield strength increased from 340 to 950 MPa as rolling temperature decreased from 1373 K to 773 K. Both the grain refinement and the work-hardening contributed to the strengthening.