Influence of Surface Segregation on the Mechanical Property of Metallic Alloy Nanowires

Abstract

ABSTRACTThe influence of surface segregation on the elastic properties of Pt-M (M = Ni, Co, or Fe) nanowires (NWs) are examined by comparing the predicted Young’s moduli of the segregated and non-segregated nanowires using density functional theory (DFT) calculations and the computed stress-strain curves under tensile loading using molecular dynamics (MD) simulation method. The moduli of the segregated NWs were found to be higher than that of the non-segregated ones. It is believed that the surface segregation increases the number of Pt-M bonds across the outermost and second surface layers, and thus enhances the Young’s modulus of the segregated Pt-M nanowires. MD results confirm our DFT results and it is found that onset of plastic deformation could be altered by the surface segregation process, as well.