Buckling and postbuckling analysis of single-walled carbon nanotubes in thermal environments via molecular dynamics simulation

Buckling and postbuckling analysis of single-walled carbon nanotubes (SWCNTs) with ( n, n)- and ( n, 0)-helicity, when acted upon by the destabilizing loads of axial compression, torsion and external pressure, is presented by using molecular dynamics simulation. Based on the interatomic interactions given by Brenner and Lennard–Jones potentials, the molecular dynamics method is used to determine the postbuckling equilibrium paths as well as the variation of strain energy. Temperature changes and van der Waals interaction forces between the opposite walls of SWCNTs are both taken into account. Comprehensive numerical results for armchair (12, 12)- and zigzag (21, 0)-tubes are presented. The results reveal that the effect of van der Waals interactions on the postbuckling behavior of SWCNTs under axial compression can be negligible, while the additional van der Waals forces will affect the postbuckling equilibrium paths of SWCNTs under torsion and external pressure when the deformation of the tube is sufficiently large. The results also show that the temperature change has a significant effect on the postbuckling response of SWCNTs under axial compression, but it has a small effect in the loading case of torsion. In contrast, it only has a less effect on the postbuckling response of SWCNTs under external pressure.