Tensile behaviour of single-crystal nano-sized Cu beams - geometric scaling effects

In this paper the mechanical response of single-crystal nano-sized Cu beams of different sizes, loaded in displacement controlled tension under constant strain rate is investigated through 3D molecular dynamic simulations using the free-ware LAMMPS. The effects from pure geometric scaling are determined for two different crystallographic orientations of the lattice. Stress-strain curves were recorded until rupture of the beams and the developments of the atomic arrangements were followed in detail. The elastic parts of the curves showed to be non-linear and that size effects to some extend influenced the elastic and significantly the plastic mechanical response. Further the crystallographic orientation markedly influenced the response to mechanical loading.