Nanodiffraction Strain Mapping of Metallic Glasses During In Situ Deformation

Abstract

Bulk metallic glasses are an exciting class of materials. Their mechanical properties are fundamentally different from their crystalline counterparts, due to the disordered structure. An experimental understanding of the fundamental deformation mechanisms of metallic glasses at the nanoscale is still lacking. Therefore, in situ deformation is carried out inside a transmission electron microscope. Scanning nanobeam electron diffraction is used to map the local elastic strain during deformation. The strain maps are determined by fitting an ellipse to the first order diffraction ring at every probe position. A direct electron detector enables acquiring the diffraction patterns at a sufficient speed to perform strain mapping during continuous in situ deformation.