氮化硼、碳化硅、锗纳米管的熔化与拉伸力学特性

摘要

Melting and tension of single-wall BN,SiC,Ge nanotubes are calculated through the MD (molecular dynamics) method,and the conductivity-temperature and load-strain curves of the nanotubes are given.According to the obtained results,the differences in conductivity and tensile-properties of several nanotubes are investigated.The results show that the melting BN tube has the net-like configuration,the SiC tube the loose ball-like one,and the Ge tube the compact sphere-like one;the BN and SiC nanotubes have much lower energy but much higher melting temperature,specific heat and melting heat than the Ge tube,which implies that the BN and SiC nanotubes have a much better stability than the Ge-tube;of three nanotubes the Ge tube has lowest anti-deformation and anti-load capability,the BN tube the highest anti-load capability,and the BN,SiC tubes have the comparable anti-load capability.%该论文采用Tersoff势的分子动力学方法分析了单壁(5,5)氮化硼、碳化硅、锗纳米管的熔化与轴向拉伸力学特性,讨论了三种纳米管熔化与轴向拉伸力学性能的差异.研究表明:氮化硼管熔化后呈现为网状,碳化硅管为疏松的不规则的团状,锗管呈现为紧密排布的近似球状;相同温度下,碳化硅及氮化硼纳米管的熔点、比热容以及熔化热却均远高于锗管,但系统能量却远低于锗管;三种纳米管中,氮化硼管的抗变形抗能力最大,锗管的抗变形与抗载荷能力最小,而氮化硼、碳化硅管的抗载荷能力相当.