(Georgia Institute of Technology, 2008-06)
Lucas, Marcel; Leach, Austin M.; McDowell, Matthew T.; Hunyadi, Simona E.; Gall, Ken; Murphy, Catherine J.; Riedo, Elisa
The plastic deformation of a pentagonal silver nanowire is studied by nanoindentation using an atomic force microscope (AFM). AFM images of the residual indent reveal the formation of a neck and surface atomic steps. To study the microscopic deformation mechanism, the indentation force-depth curve is converted to an indentation stress-strain curve and compared to the tensile stress-strain curves predicted by the atomistic simulations
of pentagonal silver nanowires. The indentation stress-strain curve exhibits a series of yielding events, attributed to the nucleation and movement of dislocations. The maximum stress measured during nanoindentation (2 Gpa ) is comparable to the tensile yield strength predicted by atomistic simulations.