Twip公司
材料科学
夏比冲击试验
奥氏体
韧性
晶体孪晶
可塑性
层错能
变形机理
变形(气象学)
冶金
复合材料
微观结构
断裂韧性
位错
马氏体
铁氧体(磁铁)
延展性(地球科学)
极限抗拉强度
电子背散射衍射
碳化物
脆化
贝氏体
蠕动
作者
Hyunmin Kim,Yumi Ha,Ki Hyuk Kwon,Minju Kang,Nack J. Kim,Sunghak Lee
标识
DOI:10.1016/j.actamat.2014.11.027
摘要
In this study, the Charpy impact toughness of three austenitic high-Mn steels was evaluated at room and cryogenic temperatures, and interpreted by deformation mechanisms in relation to the microstructural evolution of dynamically compressed specimens. Under dynamic compressive loading, nanocell structures composed of subgrains were formed by the reaction with twins and dislocations, and resulted in a high-strain-rate deformation mechanism that enhanced the strength, ductility and toughness within the stacking fault energy (SFE) range of the twinning-induced plasticity (TWIP) mechanism at room temperature. At cryogenic temperature, the formation of nanocell structures was activated with increasing Mn content, which showed the opposite trend to the room-temperature case. Since the cryogenic-temperature SFEs were lower by ∼30% than the room-temperature SFEs, a considerable amount of ε-martensite was formed in the 0.4C–22Mn steel by the transformation-induced plasticity (TRIP) mechanism, while the TWIP mechanism was working, thereby leading to increased Charpy toughness compared to the 0.4C–24Mn and 0.4C–26Mn steels. The Charpy impact toughness results were discussed using a new schematic diagram of deformation mechanisms based on SFE, loading condition and test temperature.
科研通智能强力驱动
Strongly Powered by AbleSci AI