A temperature related study on bifurcation strain and force of carbon nanotubes

[Display omitted] •A continuum theory incorporating interatomic potentials and finite temperature is developed.•Bifurcation strain and force of single-walled carbon nanotube with thermo effect is studied.•The relation between the bifurcation strain of SWNT and the finite temperature is obtained.•The relation between Young’s modulus and the temperature is also investigated.•Bifurcation strain of SWNT under tension decreases with the increase of temperature. In this paper, a new continuum theory incorporating interatomic potentials and finite temperature is developed to study the bifurcation strain and force of single-walled carbon nanotube (SWNT) under the action of tension. The effect of a finite temperature is studied using the Helmholtz free energy and the local harmonic approximation. The bifurcation strain and force of SWNT subjected to tension versus finite temperatures are predicted. It is found that the bifurcation strain of SWNT under the tension decreases almost monotonically with increasing temperatures. The bifurcation force of SWNT decreases with increasing temperatures, however, it increases with the increase of bifurcation strain and radius of SWNT. The relation between Young’s modulus and the temperature is also investigated.