title: Three-dimensional imaging of shear bands in bulk metallic glass composites.
abstract: The mechanism of the increase in ductility in bulk metallic glass matrix composites over monolithic bulk metallic glasses is to date little understood, primarily because the interplay between dislocations in the crystalline phase and shear bands in the glass could neither be imaged nor modelled in a validated way. To overcome this roadblock, we show that shear bands can be imaged in three dimensions by atom probe tomography from density variations in the reconstructed atomic density, which density-functional theory suggests being a local-work function effect. Imaging of near-interface shear bands in Ti48Zr20V12Cu5Be15bulk metallic glass matrix composite permits measurement of their composition, thickness, branching and interactions with the dendrite interface. These results confirm that shear bands here nucleate from stress concentrations in the glass due to intense, localized plastic deformation in the dendrites rather than intrinsic structural inhomogeneities.
authors: Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan, U.S.A.
authors: A H
authors: AH
authors: Hunter
authors: Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan, U.S.A.
authors: V
authors: V
authors: Araullo-Peters
authors: Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio, U.S.A.
authors: M
authors: M
authors: Gibbons
authors: Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio, U.S.A.
authors: O D
authors: OD
authors: Restrepo
authors: Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio, U.S.A.
authors: S R
authors: SR
authors: Niezgoda
authors: Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio, U.S.A.
authors: W
authors: W
authors: Windl
authors: Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University, St. Louis, Missouri, U.S.A.
authors: K M
authors: KM
authors: Flores
authors: Jet Propulsion Laboratory/California Institute of Technology, Pasadena, California, U.S.A.
authors: D C
authors: DC
authors: Hofmann
authors: Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan, U.S.A.
authors: E A
authors: EA
authors: Marquis
keywords: Atom probe tomography; density-functional theory; shear band