Cargando…

Strain rate dependency of dislocation plasticity

Dislocation glide is a general deformation mode, governing the strength of metals. Via discrete dislocation dynamics and molecular dynamics simulations, we investigate the strain rate and dislocation density dependence of the strength of bulk copper and aluminum single crystals. An analytical relati...

Descripción completa

Detalles Bibliográficos
Autores principales: Fan, Haidong, Wang, Qingyuan, El-Awady, Jaafar A., Raabe, Dierk, Zaiser, Michael
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7988163/
https://www.ncbi.nlm.nih.gov/pubmed/33758183
http://dx.doi.org/10.1038/s41467-021-21939-1
_version_ 1783668738136997888
author Fan, Haidong
Wang, Qingyuan
El-Awady, Jaafar A.
Raabe, Dierk
Zaiser, Michael
author_facet Fan, Haidong
Wang, Qingyuan
El-Awady, Jaafar A.
Raabe, Dierk
Zaiser, Michael
author_sort Fan, Haidong
collection PubMed
description Dislocation glide is a general deformation mode, governing the strength of metals. Via discrete dislocation dynamics and molecular dynamics simulations, we investigate the strain rate and dislocation density dependence of the strength of bulk copper and aluminum single crystals. An analytical relationship between material strength, dislocation density, strain rate and dislocation mobility is proposed, which agrees well with current simulations and published experiments. Results show that material strength displays a decreasing regime (strain rate hardening) and then increasing regime (classical forest hardening) as the dislocation density increases. Accordingly, the strength displays universally, as the strain rate increases, a strain rate-independent regime followed by a strain rate hardening regime. All results are captured by a single scaling function, which relates the scaled strength to a coupling parameter between dislocation density and strain rate. Such coupling parameter also controls the localization of plasticity, fluctuations of dislocation flow and distribution of dislocation velocity.
format Online
Article
Text
id pubmed-7988163
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-79881632021-04-16 Strain rate dependency of dislocation plasticity Fan, Haidong Wang, Qingyuan El-Awady, Jaafar A. Raabe, Dierk Zaiser, Michael Nat Commun Article Dislocation glide is a general deformation mode, governing the strength of metals. Via discrete dislocation dynamics and molecular dynamics simulations, we investigate the strain rate and dislocation density dependence of the strength of bulk copper and aluminum single crystals. An analytical relationship between material strength, dislocation density, strain rate and dislocation mobility is proposed, which agrees well with current simulations and published experiments. Results show that material strength displays a decreasing regime (strain rate hardening) and then increasing regime (classical forest hardening) as the dislocation density increases. Accordingly, the strength displays universally, as the strain rate increases, a strain rate-independent regime followed by a strain rate hardening regime. All results are captured by a single scaling function, which relates the scaled strength to a coupling parameter between dislocation density and strain rate. Such coupling parameter also controls the localization of plasticity, fluctuations of dislocation flow and distribution of dislocation velocity. Nature Publishing Group UK 2021-03-23 /pmc/articles/PMC7988163/ /pubmed/33758183 http://dx.doi.org/10.1038/s41467-021-21939-1 Text en © The Author(s) 2021, corrected publication 2021 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) .
spellingShingle Article
Fan, Haidong
Wang, Qingyuan
El-Awady, Jaafar A.
Raabe, Dierk
Zaiser, Michael
Strain rate dependency of dislocation plasticity
title Strain rate dependency of dislocation plasticity
title_full Strain rate dependency of dislocation plasticity
title_fullStr Strain rate dependency of dislocation plasticity
title_full_unstemmed Strain rate dependency of dislocation plasticity
title_short Strain rate dependency of dislocation plasticity
title_sort strain rate dependency of dislocation plasticity
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7988163/
https://www.ncbi.nlm.nih.gov/pubmed/33758183
http://dx.doi.org/10.1038/s41467-021-21939-1
work_keys_str_mv AT fanhaidong strainratedependencyofdislocationplasticity
AT wangqingyuan strainratedependencyofdislocationplasticity
AT elawadyjaafara strainratedependencyofdislocationplasticity
AT raabedierk strainratedependencyofdislocationplasticity
AT zaisermichael strainratedependencyofdislocationplasticity