Atomistic analysis of nanoextrusion process for fabrication of gold nanowires

Abstract

The effects of extrusion temperature and velocity on extruded gold nanowires (NWs) are studied using molecular dynamics simulations based on the many-body embedded-atom potential. The effects are investigated in terms of atomic trajectories, common neighbor analysis, flow field, and the extruded NW length-pressing ram displacement curve. The simulation results show that NWs extruded at a temperature of 300 K are longer and have a more uniform cross-sectional area compared to those extruded at higher temperatures. Higher temperature increases the cross-sectional area of extruded NWs, whereas higher extrusion velocity decreases it. In the extrusion process, dislocations first nucleate around the mold outlet and propagate along the close-packed plane {111} toward the interior. The number of disordered structures significantly increases with increasing extrusion temperature and velocity.