Dresden 2017 – wissenschaftliches Programm
MM 61: Topical session: Dynamics, relaxation and deformation in deeply supercooled metallic liquids and glasses V - dynamical response
MM 61.5: Vortrag
Donnerstag, 23. März 2017, 13:00–13:15, IFW A
Effect of hydrogen on the pop-in behavior in a metallic glass — •Lin Tian, Moritz Hirsbrunner, Dominik Tönnies, and Cynthia Volkert — Institute of Materials Physics, University of Göttingen
Hydrogen is a detrimental element in structural materials which usually causes obvious reduction of fracture toughness. For example, hydrogen embrittlement is a well-known reason for failure of steels. In contrast, in metallic glasses, which are considered to be brittle materials, hydrogen (H) can play a beneficial roll by preventing shear band formation. In this contribution, the effect of H content on the pop-in behavior of a Zr based metallic glass (M) is studied. Samples are charged to different H content (H/M) with electrochemical hydrogen loading. Then, nanoindention with a spherical indenter is carried out on the surface of the samples. While the load of the first pop-in increases with increasing H content, the possibility of pop-ins occurring decreases. A transition from shear band dominated to homogeneous deformation is observed. This result is consistent with a study of the compression of submicron pillars in hydrogen gas environment. The suppression of shear band initiation is attributed to changes in the local environment induced by H doping, such as local strain.