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Title: Shear-band thickness and shear-band cavities in a Zr-based metallic glass

Abstract

Strain localization into shear bands in metallic glasses is typically described as a mechanism that occurs at the nano-scale, leaving behind a shear defect with a thickness of 10–20 nm. Here we sample the structure of a single system-spanning shear band that has carried all plastic flow with high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and high-energy x-ray tomography (XRT). It is found that the shear-band thickness and the density change relative to the matrix sensitively depend on position along the shear band. A wide distribution of shear-band thickness (10 nm–210 nm) and density change (–1% to –12%) is revealed. There is no obvious correlation between shear-band thickness and density change, but larger thicknesses correspond typically to higher density changes. More than 100 micron-size shear-band cavities were identified on the shear-band plane, and their three-dimensional arrangement suggests a strongly fluctuating local curvature of the shear plane. As a result, these findings urge for a more complex view of a shear band than a simple nano-scale planar defect.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3];  [1]
  1. Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
  2. Univ. of Goettingen, Goettingen (Germany)
  3. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); University of Illinois, Urbana-Champaign
OSTI Identifier:
1393189
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Acta Materialia
Additional Journal Information:
Journal Volume: 140; Journal Issue: C; Journal ID: ISSN 1359-6454
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; cavities; metallic glass; shear bands; transmission electron microscopy; x-ray tomography

Citation Formats

Liu, C., Roddatis, V., Kenesei, P., and MaaB, R. Shear-band thickness and shear-band cavities in a Zr-based metallic glass. United States: N. p., 2017. Web. doi:10.1016/j.actamat.2017.08.032.
Liu, C., Roddatis, V., Kenesei, P., & MaaB, R. Shear-band thickness and shear-band cavities in a Zr-based metallic glass. United States. doi:10.1016/j.actamat.2017.08.032.
Liu, C., Roddatis, V., Kenesei, P., and MaaB, R. Mon . "Shear-band thickness and shear-band cavities in a Zr-based metallic glass". United States. doi:10.1016/j.actamat.2017.08.032.
@article{osti_1393189,
title = {Shear-band thickness and shear-band cavities in a Zr-based metallic glass},
author = {Liu, C. and Roddatis, V. and Kenesei, P. and MaaB, R.},
abstractNote = {Strain localization into shear bands in metallic glasses is typically described as a mechanism that occurs at the nano-scale, leaving behind a shear defect with a thickness of 10–20 nm. Here we sample the structure of a single system-spanning shear band that has carried all plastic flow with high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and high-energy x-ray tomography (XRT). It is found that the shear-band thickness and the density change relative to the matrix sensitively depend on position along the shear band. A wide distribution of shear-band thickness (10 nm–210 nm) and density change (–1% to –12%) is revealed. There is no obvious correlation between shear-band thickness and density change, but larger thicknesses correspond typically to higher density changes. More than 100 micron-size shear-band cavities were identified on the shear-band plane, and their three-dimensional arrangement suggests a strongly fluctuating local curvature of the shear plane. As a result, these findings urge for a more complex view of a shear band than a simple nano-scale planar defect.},
doi = {10.1016/j.actamat.2017.08.032},
journal = {Acta Materialia},
number = C,
volume = 140,
place = {United States},
year = {Mon Aug 14 00:00:00 EDT 2017},
month = {Mon Aug 14 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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