单壁氮化硼纳米管压缩特性的分子动力学模拟

采用分子动力学方法,分别模拟完好的和含有缺陷的(7,7)扶手椅型氮化硼纳米管的轴向压缩过程.原子间的相互作用采用Tersoff多体势函数来描述.为验证结果的可靠性,同时针对(7,7)扶手椅型碳纳米管进行对比计算.结果表明,氮化硼纳米管的压缩失效模式同碳纳米管相同,均表现为管壁的局部屈曲.发现纳米管的压缩强度,如临界轴向内力在低温下受温度影响明显,并且和应变率的大小有关.然而,应变率对纳米管的弹性变形没有影响.另外,还发现空位缺陷降低了纳米管的力学性能.与完好的纳米管相比,含有缺陷的纳米管轴向压缩强度对于温度的影响并不敏感.

Compression of BN Nanotubes:A Molecular Dynamics Study

With molecular dynamics(MD) method,axial compression of both perfect and defective armchair(7,7) single-walled BN nanotubes is simulated.Tersoff potential is used to simulate interaction among atoms.To verify the method,armchair(7,7) single-walled carbon nanotubes are calculated.It shows that compressive failure mode of BN nanotubes is almost the same of carbon nanotubes,in which locally-buckling on walls are observed.It is revealed that compressive strength of nanotubes,such as critical axial load,is relat...