A comparative investigation was made of the effects produced by Stone-Wales and vacancy defects upon the mechanical performance of single-walled carbon nanotubes. The defects were varied from 1 to 4 for both vacancy defects and Stone-Wales. In order to investigate the effect of both of the defects upon the material properties of carbon nanotubes, molecular dynamics simulations were used. A series of molecular dynamics models (inclusion of number of Stone-Wales and vacancy defects) were used to simulate the effects of defects upon the mechanical performance of single-walled carbon nanotubes. Molecular dynamics simulation was carried out on a 42.59A long armchair (6,6) and (10,10) single-walled carbon nanotubes by varying relative positions and orientations. The results showed that the defects reduced the tensile strength and strain more in vacancy defects as compare to Stone-Wales. This was reduced by an average value of 23.48 and 28.2% respectively for 4 vacancy defects.Simulation results also showed that more energy was required to stabilize the structure which comprises of vacancy defects. The increase in the energy value on an average was 35.52% for 4 vacancy defects as compared to pristine carbon nanotube. The Young’s modulus of defected carbon nanotubes had also been calculated by increasing the lattice size in the successive increments of 25% by volume and it was found that the Young’s modulus of pristine carbon nanotube was weakened by 9.38% for Stone-Wales defects.

Comparative Molecular Dynamics Simulation Study of Mechanical Properties of Carbon Nanotubes with Number of Stone-Wales and Vacancy Defects. K.K.Saxena, A.Lal: Procedia Engineering, 2012, 38, 2347-55