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Title: Effects of geometric factors and shear band patterns on notch sensitivity in bulk metallic glasses

Abstract

Our recent experiments in notched bulk metallic glasses have found reduced, or insensitive, or improved strengths, while in many of these cases the ductile strain prior to final failure is enhanced. First, although the inverse notch effect is explained by a shift from shear localization to cavitation failure, it is suggested in this work that the synergistic effect between cohesive fracture at the notched area and shear bands emanating from the notch roots may extend the parametric space for the notch insensitive behavior. Second, the dependence of shear band patterns on notch geometric factors is determined by the Rudnicki-Rice theory and the free-volume-based finite element simulations. Our results suggest conditions for shear band multiplication to take place and for the shear-localization-induced failure to be delayed.

Authors:
 [1];  [2];  [3]
  1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
  3. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1329744
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Intermetallics
Additional Journal Information:
Journal Volume: 79; Journal Issue: C; Journal ID: ISSN 0966-9795
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Notch sensitivity; Cohesive crack; Shear bands

Citation Formats

Li, Weidong, Bei, Hongbin, and Gao, Yanfei. Effects of geometric factors and shear band patterns on notch sensitivity in bulk metallic glasses. United States: N. p., 2016. Web. doi:10.1016/j.intermet.2016.09.001.
Li, Weidong, Bei, Hongbin, & Gao, Yanfei. Effects of geometric factors and shear band patterns on notch sensitivity in bulk metallic glasses. United States. doi:10.1016/j.intermet.2016.09.001.
Li, Weidong, Bei, Hongbin, and Gao, Yanfei. 2016. "Effects of geometric factors and shear band patterns on notch sensitivity in bulk metallic glasses". United States. doi:10.1016/j.intermet.2016.09.001. https://www.osti.gov/servlets/purl/1329744.
@article{osti_1329744,
title = {Effects of geometric factors and shear band patterns on notch sensitivity in bulk metallic glasses},
author = {Li, Weidong and Bei, Hongbin and Gao, Yanfei},
abstractNote = {Our recent experiments in notched bulk metallic glasses have found reduced, or insensitive, or improved strengths, while in many of these cases the ductile strain prior to final failure is enhanced. First, although the inverse notch effect is explained by a shift from shear localization to cavitation failure, it is suggested in this work that the synergistic effect between cohesive fracture at the notched area and shear bands emanating from the notch roots may extend the parametric space for the notch insensitive behavior. Second, the dependence of shear band patterns on notch geometric factors is determined by the Rudnicki-Rice theory and the free-volume-based finite element simulations. Our results suggest conditions for shear band multiplication to take place and for the shear-localization-induced failure to be delayed.},
doi = {10.1016/j.intermet.2016.09.001},
journal = {Intermetallics},
number = C,
volume = 79,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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