Mechanical degradation caused by interfacial vacancy defect in carbon–boron nitride heteronanotubes during axial compression tests

Abstract

Axial compression tests are performed on carbon–boron nitride heteronanotubes via molecular dynamics simulations. Three different chirality models with similar nanotube diameters and fixed axial lengths are used. The mechanical stability and buckling behavior are analyzed based on the variation in the interface position in the heteronanotubes. Results show that folding tends to occur in the boron nitride nanotubes owing to the difference in compressive stiffness between the carbon and boron nitride nanotubes. To analyze the effects of interfacial vacancy defects, additional models in which each constituent atom is removed from the interface are simulated. Regardless of the nanotube chirality, the mechanical stability indicators of the heteronanotube with interfacial vacancy defects are similar if the three atoms near the defect are of the same type. This is because the degree of mechanical degradation is determined by the maximum change in potential energy among the three atoms near the interfacial vacancy defect.