A simple derivation based on continuum mechanics was given, which showed that the surface stress was critical for yield strength at ultra-small scales. Molecular dynamics simulations with the modified embedded atom method were used to investigate the mechanical behaviours of single-crystalline metal nanowires under tensile loading. The calculated yield strengths, increasing with a decrease in the cross-sectional area of the nanowires, were in accord with theoretical predictions. Reorientation induced by stacking faults was observed at the nanowire edge. In addition, the mechanism of yielding was discussed in details based on the snapshots of defect evolution. The nanowires in different crystallographic orientations behaved differently in tensile deformation.

Atomistic Simulation on Size-Dependent Yield Strength and Defects Evolution of Metal Nanowires. Z.Yang, Z.Lu, Y.P.Zhao: Computational Materials Science, 2009, 46[1], 142-50