在巨大的应变下,碳纳米管的曲和曲
M R Falvo1, G J Clary, R M Taylor
1Department of Physics and Astronomy, University of North Carolina, Chapel Hill 27599, USA.
Nature
|October 23, 1997
概括
多壁碳纳米管表现出了显著的灵活性和弹性. 这些碳结构可以承受重复的大角曲而不会发生故障,这表明它们对先进材料应用的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 固体力学 固体力学是什么
背景情况:
- 碳纳米管 (CNTs) 由于其独特的石墨结构,具有出色的电气和机械性能.
- 石墨的高弹性模量表明,CNT可能是非常硬和强大的材料.
- 了解CNT的机械性能对于复合材料,纳米设备和传感器的应用至关重要,但需要单独测量.
研究的目的:
- 在高应变变形下研究多壁碳纳米管 (MWCNTs) 的机械行为.
- 确定个别MWCNT的灵活性和弹性.
- 评估MWCNT在需要高机械性能的应用中的潜力.
主要方法:
- 利用原子力显微镜 (AFM) 对单个MWCNTs施加受控的曲力.
- 对MWCNT进行重复的大角度变形.
- 观察和分析了MWCNT在变形期间和变形后的结构反应.
主要成果:
- MWCNTs展示了通过大角度反复曲的能力.
- 在MWCNT中没有观察到灾难性故障,尽管存在很大的压力.
- 一系列的变形反应表明了固有的灵活性和弹性.
结论:
- MWCNT表现出非凡的灵活性和弹性,挑战了关于它们脆弱性的先前假设.
- 这些发现支持MWCNT作为先进应用的坚固材料的潜力.
- 在高压下MWCNT的弹性为其在结构复合材料和纳米尺度设备中的使用开辟了新的途径.
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