The effects of different defects on the elastic constants of single-walled carbon nanotubes

In this paper, based on the continuum mechanics method, we adopt the three-dimensional finite element (FE) models to study the effects of different atom vacancy defects on the elastic constants of armchair and zigzag single-walled carbon nanotubes (SWCNTs). Also, the variations of the elastic constants with the nanotube diameter and length are investigated. The diameters of SWCNTs vary from 0.5 to 4.5 nm and the lengths vary from 2.95 to 12.31 nm. The calculation results show that the diameter, the length and the defects are relatively significant factors affecting the elastic constants of SWCNTs. Among these factors, the nanotube diameter is the most significant one. For nanotube with small diameter and length, the defects studied will affect the elastic constants evidently and the largest effective proportion of defects on the elastic constants of nanotube is within 10%.