使用定量in situTEM轴向压缩对垂直对齐的碳纳米管原始捆绑的曲和断裂特征
Raz Samira1, Adam Cohen1, Rami Eliasi2
1Department of Materials Science and Engineering, The Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
Nanotechnology
|November 23, 2023
概括
这项研究详细介绍了压缩下多壁碳纳米管 (MWCNT) 捆的机械行为. 强的范德瓦尔斯力会导致协调曲,纳米颗粒会引发断裂,影响部件的可靠性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 机械工程 机械工程
背景情况:
- 垂直对齐的多壁碳纳米管 (VACNTs) 是先进应用的有希望的材料.
- 在捆绑级别了解它们的机械性能对于可靠的组件设计至关重要.
研究的目的:
- 在轴向压缩下研究原始MWCNT捆的机械变形和断裂特征.
- 使用*in situ* TEM和FEA将机械行为与捆绑形态联系起来.
主要方法:
- 使用*in situ*传输电子显微镜 (TEM) 进行MWCNT捆的轴向压缩测试.
- 同时收集力位移数据和实时TEM视频.
- 有限元素分析 (FEA) 用于建模机械反应和验证实验结果.
主要成果:
- 观察到两种变形模式:最初的弹性行为,随后在临界曲时的力平原.
- 证明了捆的协调曲,表明了显著的范德瓦尔斯 (VdW) 力量.
- 测量了MWCNT捆绑的有效模量为83.9 GPa.
- 确定纳米颗粒作为缺陷核化部位,影响骨折.
结论:
- 直接的机械测量提供了关于MWCNT束变形和断裂的见解.
- 在MWCNT捆的机械反应中,VDW力起着至关重要的作用.
- 纳米粒子作为关键缺陷点,影响捆绑完整性.
- 了解捆绑级互动对于提高VACNT组件可靠性和耐用性至关重要.
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