温度、应变率和空位缺陷对氮化硼纳米管压缩性能的影响

采用分子动力学方法，分别模拟了完好的和含有缺陷的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。结果表明，同尺寸的锯齿型氮化硼纳米管的临界轴向压缩强度高于扶手型氮化硼纳米管，这与碳纳米管的研究结果一致。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。

Effects of temperature, strain rate, and vacancies on compress behaviors of BN nanotubes

By the use of molecular dynamics (MD) method, the axial compressive process of both perfect and defective single-walled BN nanotubes was simulated. Tersoff potential was used to simulate the interactions among atoms. The results show that the critical compressive strength of zigzag BN nanotube is bigger than that of armchair BN nanotube with same size, which is consistent with carbon nanotube. It was revealed that the compressive strength of nanotubes, such as the critical axial load, is related to applied strain rate and also affected by temperature especially by lower temperature. However, the elastic deformation behavior of nanotubes is not affected by the strain rate. It was also found that the vacancy defects are quite harmful to the mechanical properties. In comparison to perfect nanotubes, the compressive axial strength of defective nanotubes is not affected by temperature significantly.