Effect of grain number on the uniaxial tensile properties of polycrystalline nickel nanowires

In recent years, nickel nanowires have been used as flexible electrode materials for their excellent mechanical properties. There are many studies on the mechanical properties of single crystal nickel nanowires, but it remains unclear for the polycrystalline nickel nanowires. In this study, using Molecular Dynamics (MD) simulation with EAM potential, the mechanical properties of polycrystalline nickel nanowires (PNWs) with different grain numbers (3, 6, 9 and 12) under uniaxial tension along the longitudinal were studied. Results shows that the fracture strength and modulus of elasticity of polycrystalline nickel nanowires decreases with the increase of the number of grains under the same size model. The fracture strength of polycrystalline nickel nanowires is 3.2∼5.7 GPa, which is much lower than that of single crystal nickel nanowires.