Torsional deformation behavior of cracked gold nano-wires

Abstract

The presence of in-homogeneity or defects in materials cannot be ignored. There is great need to understand the influence of defects on the mechanical response of nano-materials. In this study, atomistic simulations have been used to investigate the mechanical response of gold nano-wires under twisting. Simulations show that nano-wires have different elastic properties when defects are present. Embedded cracks of different sizes have been created in nano-wires to quantify in-homogeneity. The inter-atomic interactions are represented by employing an embedded-atom potential. The effect of different sizes of crack on potential energy, torque and stresses for investigating the mechanical response of a nano-wire is part of the whole investigation. It is predicted from our simulation that the presence of a crack and dimensions of the crack control the torsional response of gold nano-wires. Deviation in the behavior of gold nano-wires from continuum expectations is also discussed. The comparison of results of atomistic simulations is made with a linear elasticity model (of healthy and cracked nano-wires) to get deep insights into the nano-scale behavior of nano-wires.