The mechanical properties of defective single-walled carbon nanotubes were studied. Two types of defect, Stone-Wales and vacancy, having differing defect densities were considered. Molecular dynamics simulations were used to study mechanical properties such as the Young’s modulus, stress, and strain of armchair single-walled carbon nanotubes with an increasing number of Stone-Wales and vacancy defects, by varying their relative position and orientation. Calculations of the fundamental mechanical properties of single-walled carbon nanotubes were performed using molecular dynamics simulation of one and four vacancy defects. These reduced the average tensile strength of the nanotube by 22.61 and 24.42%, respectively, and tensile failure strain by 34.17 and 16.74%, respectively, for various diameters. In the case of Stone-Wales defects, this reduction in strength (and strain) was only 11.33% (28.88%) and 13.16% (26.70%) for one and four defects, respectively. It was concluded that, for given defect densities, vacancy defects impaired the tensile strength of nanotubes much more since such type of defect created holes or voids in the nanotubes at which failure of the nanotubes could easily initiate.

Effect of Multiple Stone-Wales and Vacancy Defects on the Mechanical Behavior of Carbon Nanotubes using Molecular Dynamics. K.Sharma, K.K.Saxena, M.Shukla: Procedia Engineering, 2012, 38, 3373-80