Molecular dynamics simulation study of the mechanical properties of rectangular Cu nanowires

Abstract

We investigate the mechanical properties for elongation and shear of Cu nanowires. As the stretch velocity increased, the strains occurring the first yield and the rupture decrease, the period of yielding gels shorter, and the magnitude of force relaxation decreases. The first yield and the rupture at the high stretch velocity occur faster than those at low stretch velocity, and the period of yielding and the magnitudes of force relaxation at high stretch velocity are less than those at low stretch velocity. Before the first yielding, nanowires preserve the elastic stages, and after that, the elongation deformation proceeds to alternate quasi-elastic and yielding stages. The deformation preferentially takes place by slips in {111} planes. In the cases of thick nanowires, the centers: layers of the original {100} nanowire change to and remain in {111} planes because long and energetic relaxation processes for an atomic rearrangement is necessary. Homogeneous slip occurs in the shear processes of thin Cu {100} nanowire with high stretch velocity.