碳纳米管弯曲和拉伸等效弹性模量的计算分析  

Analysis of Equivalent Elastic Modulus of Single-Walled Carbon Nanotube Under Bending and Tensile Load

作　　者：曾攀[1] 

机构地区：[1]清华大学机械工程系,北京100084

出　　处：《纳米技术与精密工程》2005年第1期8-12,共5页Nanotechnology and Precision Engineering

基　　金：国家自然科学基金资助项目(10172054).

摘　　要：碳纳米管中的结合键为C—C共价键,它有3个特征参数:键能、键长和键角.首先给出C—C键合关系的坐标描述,然后基于对势函数定义了相应的势能泛函,并建立了相应的计算模型,系统分析了不同手性矢量参数单壁碳纳米管在拉伸和弯曲情形下的力学行为,基于实验结果,按碳纳米管的中空结构计算了相应的等效弹性模量,研究了扶手椅型SWNT(3,3)～SWNT(14,14)的等效弹性模量变化规律.研究结果表明,在拉伸和弯曲情形下,按碳纳米管中空结构计算得到的等效弹性模量为237～239GPa,泊松比为0.21.该结果具有实验上的统计性质.The atomistic binding of carbon nanotube is a typical covalent C—C bond with three characteristic parameters: bond energy, bond length and bond angle. First of all, the coordinate description for atomistic C—C bonding is presented. Then based on potential functional, a numerical analytical model is proposed to study the elastic behavior of SWNT(single-walled carbon nanotube). This model is applied to investigate the mechanical behaviors of SWNT under bending and tensile load. Considering the hollow structure characteristics of SWNT, an equivalent formula is used to compute and define the Young’s modulus and Poisson’s ratio, and further to investigate the elastic behaviors of a series of armchair carbon nanotubes (from SWNT(3,3) to SWNT(14,14)). Research results show that the computed equivalent Young’s modulus considering the hollow structure characteristics is between 237 GPa and 239 GPa, Poisson’s ratio is 0.21, both for tensile case and bending case. This value of Young’s modulus is with experimental statistics property.

关 键 词：等效弹性模量 键角 键长 泛函 键能 手性 中空结构 单壁碳纳米管 拉伸 泊松比 

分 类 号：TB383[一般工业技术—材料科学与工程]