Abstract High carbon martensite possesses outstanding hardness and strength but poor ductility, even though it consists of numerous twins which have been regarded as the favorable structure for deformation in metals and alloys. So far, the role of high density of twins in the conflict, fully twined structure and poor ductility, in high carbon martensite is not clear. In this letter, we proposed an atomic mechanism for the formation of nanotwins to reveal the nature of poor ductility of high carbon martensite. This mechanism suggests that interstitial carbon atoms stabilize ω phase which facilitates the nucleation and termination of {112} type nanotwins in high carbon martensite. The nanoscale ω particles embedded in boundaries of nanotwins pins naonotwins, impeding the motion of twins in the martensite. This mechanism constructs a correlation between the nanotwins and poor ductility of martensite in high carbon steels.

中文翻译：

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在高碳马氏体中形成纳米孪晶的原子机制

摘要 高碳马氏体虽然由大量孪晶组成，被认为是金属和合金变形的有利组织，但具有优异的硬度和强度，但延展性较差。迄今为止，在高碳马氏体中，高密度孪晶在冲突中的作用、完全孪晶组织和差的延展性尚不清楚。在这封信中，我们提出了形成纳米孪晶的原子机制，以揭示高碳马氏体延展性差的性质。这种机制表明间隙碳原子稳定了 ω 相，这有利于高碳马氏体中 {112} 型纳米孪晶的成核和终止。嵌入纳米孪晶边界的纳米级 ω 粒子固定了 naonotwins，阻碍了马氏体中孪晶的运动。