Copper Nanobelt Reorientation by Molecular Dynamics Simulation

Atomic simulations using embedded atom method (EAM) are performed for Cu <100> nanobelts to study the structural and mechanical behaviour. Cu <100> nanobelts are along 001 taken as the z-axis and have a rectangular cross section in the x-y plane, with 100 and 010 taken as x and y axes. The periodic boundary is used along the z-axis to simulate an infinitely long nanobelt, and other surfaces are free. The simulations are carried out under the mechanical loading with an elongation strain rate of 8.0×10⁸s^-1 along the z-axis. The results show that the nanobelt undergoes a transition from the initial structure with a <100> axis and 100 lateral surfaces to a new structure with the <112> as the z-axis and the lateral surfaces are 111 and 110 respectively, instead of the original 100 surfaces. The mechanism of the structural transition is ascribed to the dislocation propagation through the nanobelt under the external stresses.