Dresden 2009 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 43: Liquid and Amorphous Metals II

MM 43.1: Vortrag

Donnerstag, 26. März 2009, 16:00–16:15, IFW A

serrated flow behavior in bulk metallic glasses — •gang wang, norbert mattern, and jürgen eckert — Institute of complex materials, IFW-Dresden, 01069 Dresden, Germany

Plastic deformation of bulk metallic glasses (BMGs) is a complex inhomogeneous process characterized by avalanches in the motion of shear bands. In the present study, based on the CuZr-based BMG, we investigate the serrated flow behavior in the plastic deformation stage. We statistically analyze the serrated stress-strain behavior of BMGs with different plastic deformation ability. The cumulative possibility distribution of the elastic energy density follows the Weibull distribution. Accompanying with the compression tests, we measured the atomic-scale strain during the serrated flow stage by x-ray synchrotron radiation at room temperature. High resolution strain scanning reveals the relationship between the macroscopic serrated flow and the atomic-scale elasto-plastic deformation. Based on the potential energy landscape (PEL) theory of ductile glasses, we attempt to construct a clear physic image of the origination of the plastic deformation in glassy phase, i.e. the evolution from the disorder atomic cluster, to shear transforming zone (STZ) formation, to shear bands origination and then to the shear slip occurring.