Three-point bending behavior of a Au nanowire studied by in-situ Laue micro-diffraction

Abstract

The elastic and plastic deformation of a gold nanowire tested in a three-point bending configuration using the custom-built scanning force microscope SFINX was studied in situ by Laue micro-diffraction. A new data treatment method based on the integration of diffraction patterns recorded along the deformed nanostructure is introduced visualizing both the movement and shape of the diffraction peaks as a function of the measurement position. Besides bending, torsion is evidenced during the elastic deformation originating from a misalignment of the SFINX-tip of the order of 60 nm with respect to the nanowire center. As demonstrated by post-mortem Laue micro-diffraction maps, the plastic deformation is governed by the storage of geometrically necessary dislocations. Analyzing the shape of the diffraction peaks, the activation of two unexpected slip systems is found which does not coincide with the slip systems with the highest resolved shear stress. These unexpected slip systems are probably related to the dislocation nucleation process at the clamping point, which is influenced by the local curvature.