The tempering behavior of granular structure in a Mn-series low carbon steel

▶ The granular structure in the Mn-series low carbon steel designed by us does not exhibit temper brittleness within the whole range of tempering temperature. This phenomenon is novel since common microstructures in steels usually have temper brittleness. ▶ The impact toughness and tensile strength of the granular structure do not change greatly after tempering below a relatively high temperature, implying a high temper stability of the granular structure. ▶ The tempering behavior of the granular structure is discussed through studying the microstructure evolution during tempering.