使用分子动力学模拟在纳米缩下揭示钻石类碳的塑性变形机制
Keke Meng1, Xin Zhang1, Xiaolong An1
1School of Mechanical Engineering, Inner Mongolia University of Science & Technology, Baotou 014010, China.
Langmuir : the ACS journal of surfaces and colloids
|September 2, 2025
概括
分子动力学模拟显示,类似钻石的碳 (DLC) 的可塑性来源于sp2-C结构中的sp3-C位点. 这种可塑性涉及动态原子重新排列和混合过渡,为改进DLC机制提供了洞察力.
科学领域:
- 材料科学
- 部落学
- 计算物理
背景情况:
- 类似钻石的碳 (DLC) 具有非常重要的机械特性.
- 在先进的DLC中,了解变形机制,特别是塑性行为是具有挑战性的.
研究的目的:
- 通过分子动力学 (MD) 模拟来研究纳米缩下DLC的原子级变形机制.
- 阐明自由体积和杂交状态在DLC可塑性的作用.
主要方法:
- 进行了原子分子动力学 (MD) 模拟,以模拟DLC上的纳米痕.
- 分析包括剪切应变,原子位移,杂交状态,应力张量和原子集群.
主要成果:
- 塑性始于具有高自由体积的区域,特别是在sp2-C结构中的sp3-C位点.
- 变形涉及离散的原子重新排列和碳杂交状态 (sp2,sp3) 之间的动态,部分可逆过渡.
- 由剪切转换促进的sp2-sp3转换发生在低于预期的应力值.
结论:
- 这项研究提供了对DLC可塑性的起源和机制的基本见解.
- 这些发现表明修改DLC以提高其机械性能的潜在途径.
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