Anisotropic and temperature effects on mechanical properties of copper nanowires under tensile loading

Atomistic simulations are used to investigate the mechanical properties of copper nanowires (NWs) along 〈1 0 0〉, 〈1 1 0〉 and 〈1 1 1〉 crystallographic orientations under tensile loading at different temperatures. The inter-atomic interactions are represented by employing embedded-atom potential. To identify the defects evolution and deformation mechanism, a centrosymmetry parameter is defined and implemented in the self-developed program. The simulations show that Cu NWs in different crystallographic orientations behave differently in elongation deformations. The stress–strain responses are followed by a particular discussion on yield mechanism of NWs from the standpoint of dislocation moving. Generally, the study on the incipient plastic deformation will be helpful to further understanding of the mechanical properties of nanomaterials. In addition, the Young’s modulus decreased linearly with the increase of temperature. The crystal structure is less stable at elevated temperatures.

► Tensile loaded Cu nanowires are studied by atomistic simulation. ► The mechanical properties are found to be orientation-dependent. ► The mechanism is discussed in detail based on the snapshots of defects evolution. ► The temperature effect on the stability of Cu nanowires is also investigated. ► The Young’s modulus decreases linearly with temperature increasing.