Simulation of mechanical response of point defects in copper

A molecular dynamics simulation has been performed to investigate the dynamical nature and the mechanical response of self-interstitials in copper. The embedded-atom method potential developed by the present authors is adopted to express the atomic interaction in crystals. The static configuration and the interaction with the elastic vibration are simulated, and the internal friction by the interstitial is evaluated from the damping of elastic vibration. The motion of interstitial atoms in the vibrating crystal is analyzed through the trajectory of the motion of atoms. The trajectory for the thermal motion of interstitial atoms at elevated temperatures is also derived and the thermal migration of interstitials is investigated.