Effect of Different Heat Treatment Processes on Microstructure Evolution and Tensile Properties of Hot-Rolled Medium-Mn Steel

The effects of different heat treatment processes on microstructure evolution and tensile properties of Fe-0.11C-5.23Mn-1.11Al-0.10Si medium-Mn steel were investigated. The uniaxial tensile properties of tension specimens after heat treatment were tested, and the relationship between different annealed microstructures and tensile properties was analyzed; furthermore, the optimum heat treatment parameters were explored. Besides, the water-quenched sample exhibited an extensive TRIP effect than the furnace-cooled sample. The optimum microstructure and mechanical properties can be obtained when the sample is intercritically annealed at 625 °C for 4 h and then water-quenched. At the same time, the work hardening rate of the experimental steel is expounded, which provides theoretical reserve and technical support for the practical application of this kind of steel.