Dresden 2017 – wissenschaftliches Programm
MM 61: Topical session: Dynamics, relaxation and deformation in deeply supercooled metallic liquids and glasses V - dynamical response
MM 61.2: Vortrag
Donnerstag, 23. März 2017, 12:15–12:30, IFW A
Plastic deformation mechanism of metallic glasses — •Vitalij Hieronymus-Schmidt1, Harald Rösner1, Alessio Zaccone2, and Gerhard Wilde1 — 1Institut für Materialphysik, Universität Münster, Deutschland — 2University of Cambridge, Cambridge, U.K.
Deformation of metallic glasses performed well below the glass transition temperature leads to the formation of shear bands, narrow regions in which the plastic flow is confined. It is believed that shear banding originates from individual stress concentrators having quadrupolar stress symmetry. To elucidate the underlying mechanisms of shear band formation, microstructural investigations were carried out on sheared zones using transmission electron microscopy. An evidence of a characteristic signature present in shear bands manifested in the form of sinusoidal density variations was found. On this basis we present an analytical solution for the observed post-deformation state derived from continuum mechanics using an alignment of quadrupolar stress field perturbations for the plastic events. Since we observe qualitatively similar features for three different types of metallic glasses that span the entire range of characteristic properties of metallic glasses, we suggest that the reported deformation behavior is generic for all metallic glasses, and thus has far-reaching consequences for the deformation behavior of amorphous solids in general.