论文标题
钻石中的脱位滑移或相转换导致室温可塑性：对单晶钻石纳米骨的塑性变形的评论
Dislocation Slip or Phase Transformation Lead to Room-Temperature Plasticity in Diamond: Comment on Plastic Deformation of Single-Crystal Diamond Nanopillars
论文作者
论文摘要
尽管数十年来对钻石的机械性能进行了数十年的研究，但由于室温下的变形性差，在塑性变形机制方面仍有许多理解。在最新的高级材料中，据称基于扫描电子显微镜内部未恢复的变形，<i001>面向的单晶钻石纳米骨骼中发生了室温可塑性。建议通过分子动力学模拟从SP3碳到O8-碳相的相变向O8-碳相的相变介导。相比之下，我们的原位透射电子显微镜研究表明，室温可塑性可以通过<100>和<111> <111>的导向的钻石纳米骨中的脱位来执行。脆性转变高度取决于应力状态。我们注意到，表面结构在变形机制中可能起重要作用，因为始终发生的可塑性总是来自纳米级钻石的表面区域。
Despite decades of extensive research on mechanical properties of diamond, much remains to be understood in term of plastic deformation mechanisms due to the poor deformability at room temperature. In a recent work in Advanced Materials, it was claimed that room-temperature plasticity occurred in <001>-oriented single-crystal diamond nanopillars based on observation of unrecovered deformation inside scanning electron microscope. The plastic deformation was suggested to be mediated by a phase transition from sp3 carbon to an O8-carbon phase by molecular dynamics simulations. By comparison, our in-situ transmission electron microscopy study reveals that the room-temperature plasticity can be carried out by dislocation slip in both <100> and <111>-oriented diamond nanopillars. The brittle-to-ductile transition is highly dependent on the stress state. We note that the surface structure may play a significant role in the deformation mechanisms as the incipient plasticity always occurs from the surface region in nanoscale diamonds.
