系统地研究类似钻石的碳的拉伸和压缩行为
Jingxiang Xu1, Yina Geng1, Zhenhua Chu1
1College of Engineering Science and Technology, Shanghai Ocean University, Shanghai 201306, China.
Nanomaterials (Basel, Switzerland)
|June 10, 2023
概括
钻石状碳 (DLC) 的机械性能随温度和密度而变化. 较高的温度减少了DLC的使用.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算物理 计算物理
背景情况:
- 类似钻石的碳 (DLC) 涂层对于耐磨性和阻尼性至关重要.
- 了解DLC在不同条件下的机械行为对于高级应用程序至关重要.
- 温度和密度显著影响DLC的机械性能,限制了当前的应用.
研究的目的:
- 系统地研究在不同温度和密度下钻石状碳 (DLC) 的变形行为.
- 为了阐明温度和密度对DLC在拉伸和压力负荷时的机械反应的影响.
主要方法:
- 用分子动力学 (MD) 模拟来建模DLC.
- 压缩和拉伸测试模拟在300K至900K的温度范围内进行.
- 分析了不同密度的DLC模型.
主要成果:
- 温度升高 (300K至900K) 导致拉伸和压缩应力降低,拉伸和压缩应力增加.
- 在拉力模拟中的模块在更密集的DLC模型中显示出更高的温度灵敏度.
- 压缩变形主要由Csp2-Csp3过渡和相对滑动,而拉伸变形涉及Csp3-Csp2过渡.
结论:
- 温度显著影响DLC的机械变形,特别是拉伸性能.
- 在拉伸应力过程中,DLC密度会影响扬模块在拉伸应力过程中的温度灵敏度.
- 特定的原子转换 (Csp3-Csp2和Csp2-Csp3) 和滑动机制决定了DLC对不同机械负荷的反应.
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