(S215)Toughness and fracture behavior of thermo-mechanical control processed medium Mn martensitic steel

摘要

Medium Mn steel is recently expected as a candidate for the next generation high strength structural steel because of its excellent strength-ductility balance. However, the Mn addition results in an embrittlement of steel due to the weakening of grain boundary leading to an intergranular fracture. In our previous report, we applied thermo-mechanical control process (TMCP) to Fe-10Mn-0.1C alloy to improve its toughness, and found that the absorbed energy was drastically improved when a low-temperature TMCP was performed 1. In this study, the morphology of fracture surface of the TMCPed medium Mn steel was investigated in detail in order to reveal its fracture mechanism.