INVESTIGATION OF TEMPERATURE, CHIRALITY, SIZE, AND BOUNDARY CONDITIONS EFFECT ON THE TENSILE PROPERTIES OF SINGLE-WALLED CARBON NANOTUBE (SWCNT) BY MOLECULAR DYNAMIC APPROACH

Tensile properties of single-walled carbon nanotubes (SWCNTs) have been determined using molecular dynamics (MD) simulation. AtomsK<sup>®</sup> was used to generate the large-scale atomic/molecular massively parallel simulator (Lammps<sup>®</sup>) data file, and OVITO was used to visualize the dump file. The molecular dynamics study examined how temperature, strain rate, size of carbon nanotube (CNT), chirality, and boundary conditions might affect the tensile characteristics of a typical SWCNT. Five intermediate temperatures were chosen: 300, 350, 400, 450, and 500 K. The findings showed that strength decreased when the temperature rose due to structural changes, thermally induced faults, thermal deterioration, and thermal expansion. To further examine how strain rate affects the tensile behavior of the material at 300 K, three strain rates of 0.25 × 10<sup>–3</sup>, 0.5 × 10<sup>–3</sup>, and 1 × 10<sup>–3</sup> were selected. It was shown that SWCNT networks displayed strain rate-dependent behavior, with greater strain rates resulting in higher strength values; this feature is known as strain-rate sensitivity. Tensile properties were also observed for three different sizes of CNT. From computational results, it can be concluded that the tensile strength of SWCNT decreased with increasing in radius of SWCNT. Also, the mechanical properties of SWCNT for different chirality and boundary conditions were compared. It showed that the strength of the armchair arrangement was higher than the strength of the zigzag orientation.