拉伸条件下双壁碳纳米管弹性性能的原子模拟

利用分子动力学方法，对双壁碳纳米管在拉伸条件下的弹性性能进行模拟，研究了直径在1 nm以上的4根双壁碳纳米管，模拟了它们的应力-应变关系以及泊松比.计算结果表明，在弹性范围内，双壁碳纳米管的应力与应变呈非线性关系，切线弹性模量大致从720 GPa减小至570 GPa，出现软化现象；随着拉伸应变的增大，泊松比从0.3变化到0.17，但结构尺寸对泊松比的影响不大. 关键词： 双壁碳纳米管 分子动力学 弹性模量 泊松比

Atomic modeling on the elastic properties of double-walled carbon nanotubes under tension

The stress versus strain relations and the Poisson's ratios under tension of 4 double-walled carbon nanotubes (DWCNTs) with diameters greater than 1 nm were numerically studied with the molecular dynamics method. The simulation shows that in the elastic range the stress and the strain have nonlinear relation, and the tangent elastic moduli of the DWCNTs decrease from 720 to 570 GPa with increasing strain. As the strain increases, the value of Poisson's ratio changes from 0.3 to 0.17, and the sizes of the DWCNTs have little influences on the Poisson's ratio.