Ductile to brittle transition is critical to achieve nanometric surfaces in the ultraprecision diamond cutting of silicon carbide. Although atomic simulations have long been used to better understand this mechanism, the extremely small model scale limits its capability in matching the actual cutting process. To overcome this serious issue, an enhanced molecular dynamics method is proposed in this study, which successfully predicts and clarifies the onset of brittle regime machining, and indicates the essential roles of dislocation and the shear band. The experimental results validate the effectiveness of this modelling approach.

中文翻译：

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碳化硅的纳米切割机理

韧性到脆性的转变对于在碳化硅的超精密金刚石切割中实现纳米表面至关重要。尽管长期以来一直使用原子模拟来更好地理解这种机制，但极小的模型规模限制了其匹配实际切割过程的能力。为了克服这个严重的问题，本研究提出了一种增强的分子动力学方法，它成功地预测和澄清了脆性加工的开始，并指出了位错和剪切带的重要作用。实验结果验证了这种建模方法的有效性。