【摘要】 基于分子结构力学方法,应用APDL(ANSYS Parametric Design Language)参数化编程,建立了含S-W(Stone-Wales)缺陷的单壁碳纳米管有限元模型。提出方向角的概念以表征缺陷的不同类型。对一系列含S-W缺陷的单壁碳纳米管进行轴向拉伸和纯扭转的仿真计算,揭示出缺陷类型、数量和排列方式对其力学性能的影响规律。结果表明,弹性和剪切模量都会因缺陷的存在而出现不同程度的折损,特殊情况下反而上升,可从能量观点加以解释。缺陷的类型和排列方式决定其对弹性和剪切模量的影响趋势;当缺陷的类型和排列方式一定时,弹性和剪切模量的折损率与缺陷数量大致成正比。所得结论对实际含缺陷碳纳米管力学性能的评估和缺陷状况的预测均具有指导意义。更多还原

【Abstract】 Based on the molecular structural mechanics approach,a Finite Element(FE) model for varieties of Single-Walled Carbon Nanotubes(SWCNT) with Stone-Wales(S-W) defects is proposed employing the ANSYS Parametric Design Language(APDL) for parametric modeling.To characterize different types of S-W defects,a concept of direction angle is introduced.The axial tension and torsion behaviors of SWCNTs with S-W defects are simulated,and the effects of type,quantity and array of defects on mechanical properties of SWCNTs are revealed in detail.The results show that the Young’s modulus and shear modulus decrease due to the existence of defects,with individual exceptions which can be explained from the view point of energy.The type and array of defects determine their influence tendency on Young’s modulus and shear modulus;the loss rates of the two moduli are approximately proportional to the amount of defects with the same type and array of defects.The results can guide the estimating of mechanical properties of SWCNTs with S-W defects and predicting the defects in SWCNTs.更多还原