A molecular dynamics simulation of the mechanical characteristics of a C60-filled carbon nanotube under nanoindentation using various carbon nanotube tips

The mechanical characteristics of a single-walled carbon nanotube (SWCNT) filled with C₆₀ fullerene subject to nanoindentation is studied using molecular dynamics (MD) simulations. The effects of temperature, indentation velocity, adhesion, and tip sizes were evaluated. The simulated results clearly show that the exerted load, Young’s modulus, elastic energy, and plastic energy decrease significantly with increasing temperature and decreasing indentation velocity and tip size. C₆₀ fullerenes can effectively increase the mechanical strength of a SWCNT because they act as a “barrier” to resist the radial deformation, as well as an inner wall in a double-walled carbon nanotube. With the same indentation depth, the ratio of elastic energy to plastic energy for a material gradually increases with the increase in the radius of the tip. This indicates that the elastic recovery of a material is better when the tip has a larger radius.