Theoretical Prediction of Tensile Behavior of Single-Walled Carbon Nanotubes
Based on molecular mechanics, a finite element model is proposed to evaluate the tensile behaviour of single-walled carbon nanotubes (SWCNT). The SWCNT is modelled as a space-frame structure. The bonds between the carbon atoms are simulated as beam members to carry the loads, while the carbon atoms are the joints of the members. The modified Morse potential is adopted to characterize the non-linear behaviour of C-C bonds. The simulation are carried out for two well-known SWCNTs, armchair and zigzag with different diameters to investigate the influence of chirality and diameter on the mechanical properties including the Youngs modulus, tensile strength and fracture strain of SWCNTs. It is found that the Youngs moduli of both armchair and zigzag nanotubes increase monotonically with the increase of diameter. The armchair nanotube exhibits larger stress-strain response than the zigzag nanotube. Numerical simulations reveal that the Youngs modulus and tensile strength of armchair nanotubes are larger than that of zigzag nanotubes. These results are in good agreement with the existing numerical and experimental results.
Keywords: Tensile behavior, single-walled carbon nanotube, molecular mechanics, finite element method, Morse potential, Young's moduli, chirality
Rights & PermissionsPrintExport