Effects of Temperature and Shape on the Tensile Behavior of Platinum Nanowires

Molecular dynamics (MD) simulation was performed on an fcc solid platinum nanowire in this study. Infinite one-dimensional nanowires of circular and rectilinear cross sectional shapes were subjected to uniaxial tensile strain, and simulated at temperatures of 50K and 300K. The constitutive stress-strain response of the nanowire was investigated, the changes in crystal structure during axial deformation was studied and mechanical properties like first yield stress and strain, rupture strain, ductility and Young’s modulus were deduced from the simulation statistics. It was observed that the nanowire with a rectilinear cross section generally exhibited greater ductility, with a correspondingly lower first yield stress and strain. The nanowire with a circular cross section displayed a higher tendency for the formation of a helical substructure during severe necking. These observations were more significant at the higher temperature of 300K. Young’s modulus at nanoscale was also investigated.