Molecular Dynamics study on buckling behavior of vertically aligned carbon nanotube (VACNT) bundles with characterized waviness

Abstract

The buckling behavior of vertically aligned carbon nanotube (VACNT) bundles with a characterized waviness ratio was studied using the principle of sinusoidal waves. A MATLAB algorithm was used to generate bundles with a user-specified waviness ratio, and 12 VACNT models were used under a constant strain of 0.01/ps uniaxial compression with three variable parameters: waviness ratio, number of VACNTs within the bundle, and presence of van der Waals interactions; moreover, the findings suggest that these parameters significantly influenced the critical buckling stress (σcomp) and buckling behavior of the bundle. Increasing the waviness resulted in a significant reduction of approximately 59.96% between a bundle with no waviness and a bundle with a waviness ratio of 0.33. Including van der Waals interactions played a critical role in strengthening the overall VACNT bundle, whereas eliminating them changed the buckling pattern and behavior of the bundles, furthermore, increasing the number of VACNTs in a bundle increased the critical buckling stress of the overall bundle. This study provides insight into the structural behavior of VACNT bundles, which is expected to impact the design of any system in which the collective mechanical behavior of the VACNT bundles is critical. These findings can improve the study of composite materials in lithium-ion batteries for high-capacity CNT composite anodes.