Transversely isotropic elastic properties of vacancy defected boron nitride nanotubes using molecular dynamics simulations

Abstract

Recent breakthroughs in the synthesis of boron nitride nanotubes (BNNTs) attracted researchers' attention again for developing their nanocomposites. This is due to the fact that BNNT possesses wide band gap (5.5 eV, independent of geometry), strong hardness, chemically and thermally stable, and excellent piezoelectric properties than its carbon-based counterpart. Furthermore, BNNTs have comparable mechanical and thermal properties compared to carbon nanotubes. As the first of its kind, this study reports the transversely isotropic elastic properties of pristine and vacancy defected BNNTs within the framework of MD simulations using a Tersoff force field. This is achieved by imposing axial extension, twist, in-plane biaxial tension, and in-plane shear to the pristine and defective BNNTs. Our results reveal that vacancy concentration of 2 % affects profoundly the axial Young's, shear, plane strain bulk and in-plane shear moduli of BNNTs, and decrease their respective values by 14%, 25%, 14% and 18%. The current fundamental study highlights the important role played by vacancy defected BNNTs in determining their mechanical behaviours as fillers in multifunctional nanocomposites. © 2018 IEEE.