Young modulus and longitudinal damping coefficient of the composite copper reinforced by carbon nanotubes

Due to the widespread use of carbon nanotubes in composites with special capabilities, in this study, the elastic constants, Q-factor, and longitudinal damping coefficient of crystalline copper reinforced by carbon nanotubes were examined exploiting molecular dynamics simulation. The effect of temperature and chirality of carbon nanotubes on the above-mentioned parameters was also investigated. The mechanical behavior of the copper composites is considered for two different carbon interatomic potentials Airebo and Tersoff. Additionally, the mechanical characteristics of the composites are pursued in the case of short carbon nanotube fibers, as well. In this work, Young's modulus and Q-factor were determined via the uniaxial stress and forced vibration method, respectively. Subsequently, employing the multi-degree of freedom structural dynamics, the longitudinal damping coefficient was obtained. The results showed that by the addition of the carbon nanotubes to the copper matrix, its Young's modulus and damping coefficient increased. A comparison between armchair, zigzag, and chiral carbon nanotubes of the same diameter and length manifested that the chiral or armchair carbon nanotubes, depending on the employed interatomic potentials, had a more dominant effect on increasing the composite Young's modulus. Moreover, the calculations show that the Q-factor in the reinforced cell was significantly reduced.