Evidence of the existence of two deformation stages in bulk metallic glasses

The deformation behavior of bulk metallic glasses and dual-phase crystal/glassy materials was analyzed using the stress-strain diagrams, in-situ video recording and subsequent macro- and micro-structure observation. As a result a two-stage deformation mechanism is observed. The stages are related to the initiation and propagation of multiple shear bands in the beginning of the deformation process as well as the formation and propagation of the dominant shear band at the later stage finally leading to large shear offsets and failure of the sample.