Torsion behavior simulation of Ni-coating SWCNT based on molecular dynamics

The effect of nickel coating upon the torsional behaviors of single-walled carbon nanotube (SWCNT) was defined, and torsion behaviors were investigated using the molecular dynamics (MD) simulation method. In this work, an armchair (6,6) carbon nanotube was considered. Both SWCNT and SCNT coating Ni (SWCNT-Ni) were analyzed at 0K and 300K. By simulating torsion process of SWCNT-Ni, mechanical behaviors of SWCNT-Ni could be defined. When torsion rate was relatively high, it had been reported that the torsional stiffness of SWCNT would reduce even at low temperature. However, to avoid the effect of torsion rate upon mechanical behaviors of SWCNT and SWCNT-Ni, an extremely low torque was applied which was corresponding to low torsion rate, and it was observed that the torsion angle of SWCNT and SWCNT-Ni were almost the same at the initial stage. That was to say, the metal coated atoms had little effect on torsional stiffness at extremely low torsion rate. When temperature rises, the effect of temperature begun to emerge. It was noted that the nickel atoms trended to rearrange, and the nickel atoms were more likely to migrate to the place of great deformation, and the torsion changed the curve of the outside surface, which caused the increase of Ni-C interactions.