Vol.4 No.12 (December 2014)
Effect of Density of Interfacial Defect on Mechanical Properties of Copper Nanowires
The effect of interfacial defect on mechanical properties of copper nanowires (NWs) containing twin boundaries (TBs) and stacking faults (SFs) is investigated using the molecular dynamics simulation. The results indicate that when the TB is coupled with interfacial defects, the strength of NWs is reduced. The density of interfacial defects influences the nucleation location regardless of the yield strength. The dislocation will emit at the adjacent perfect twin boundary or the intrinsic SF induced by the defect depending on the density of interfacial defects. However, when the interfacial defects are in the SF, the dislocation induced by the interfacial defect will slip along the SF or in the SF and eventually pile up at the junction of SF and free surface. As the emergence of stress concentration, the yield strength is also reduced. The yield strength of NWs containing SF will obviously decrease as the increase of number density of interfacial defects.
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