Effect of Inter Defect Interaction on Tensile Fatigue Behavior of a Single Walled Carbon Nanotube With Stone–Wales Defects

Abstract

A refined molecular life prediction scheme for singlewalled carbon nanotubes (SWCNTs), taking into consideration C–C bond rotation and preexisting strain under mechanical loads, is proposed. The timedependent fracture behavior of 12 different cases of zigzag (18,0) SWCNT, each embedded with either a single Stone–Wales (SW) defect of different types or two interacting or noninteracting defects, is studied under axially applied tensile load. It is shown that the patterns of atomistic crack propagation and fatigue lives of SWCNTs are influenced by the type and orientation of the SW defect(s), interdefect distance, as well as the magnitude of externally applied stress. For SWCNTs with two SW defects, if the interdefect distance is within the so called indifference length, defectdefect interaction does exist, and it has pronounced effects on diminishing the lives of the nanotubes. Also, the defectdefect interaction is stronger at shorter interdefect distance, resulting in shorter fatigue lives.