Characterization of nonlinear elasticity and elastic instability in single-walled carbon nanotubes

The behavior of single-walled carbon nanotubes (SWNT) under large scale compressive deformation, was investigated, by molecular simulations using the second-generation Brenner potential. Elastic responses of SWNTs under compression were compared with those under tension, produced under the same fixed boundary conditions. The results show that the nanotubes harden with compression but soften with tension, and the degrees of strain dependency are different. The results also show, that carbon nanotube stiffness is also dependent on chirality and the diameters.