Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear
Torsion experiments were performed in polycrystalline ice at high temperature (0.97 Tm) to reproduce the simple shear kinematics that are believed to dominate in ice streams and at the base of fast-flowing glaciers. As clearly documented more than 30 years ago, under simple shear ice develops a two-...
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00002167 2023-05-15T18:32:33+02:00 Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear Journaux, Baptiste Chauve, Thomas Montagnat, Maurine Tommasi, Andrea Barou, Fabrice Mainprice, David Gest, Léa 2019-05 electronic https://doi.org/10.5194/tc-13-1495-2019 https://noa.gwlb.de/receive/cop_mods_00002167 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00002125/tc-13-1495-2019.pdf https://tc.copernicus.org/articles/13/1495/2019/tc-13-1495-2019.pdf eng eng Copernicus Publications The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-13-1495-2019 https://noa.gwlb.de/receive/cop_mods_00002167 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00002125/tc-13-1495-2019.pdf https://tc.copernicus.org/articles/13/1495/2019/tc-13-1495-2019.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2019 ftnonlinearchiv https://doi.org/10.5194/tc-13-1495-2019 2022-02-08T23:01:14Z Torsion experiments were performed in polycrystalline ice at high temperature (0.97 Tm) to reproduce the simple shear kinematics that are believed to dominate in ice streams and at the base of fast-flowing glaciers. As clearly documented more than 30 years ago, under simple shear ice develops a two-maxima c axis crystallographic preferred orientation (CPO), which evolves rapidly into a single cluster CPO with a c axis perpendicular to the shear plane. Dynamic recrystallization mechanisms that occur in both laboratory conditions and naturally deformed ice are likely candidates to explain the observed CPO evolution. In this study, we use electron backscatter diffraction (EBSD) and automatic ice texture analyzer (AITA) to characterize the mechanisms accommodating deformation, the stress and strain heterogeneities that form under torsion of an initially isotropic polycrystalline ice sample at high temperature, and the role of dynamic recrystallization in accommodating these heterogeneities. These analyses highlight an interlocking microstructure, which results from heterogeneity-driven serrated grain boundary migration, and sub-grain boundaries composed of dislocations with a [c]-component Burgers vector, indicating that strong local stress heterogeneity develops, in particular, close to grain boundaries, even at high temperature and high finite shear strain. Based on these observations, we propose that nucleation by bulging, assisted by sub-grain boundary formation and followed by grain growth, is a very likely candidate to explain the progressive disappearance of the c axis CPO cluster at low angle to the shear plane and the stability of the one normal to it. We therefore strongly support the development of new polycrystal plasticity models limiting dislocation slip on non-basal slip systems and allowing for efficient accommodation of strain incompatibilities by an association of bulging and formation of sub-grain boundaries with a significant [c] component. Article in Journal/Newspaper The Cryosphere Niedersächsisches Online-Archiv NOA The Cryosphere 13 5 1495 1511 |
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English |
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article Verlagsveröffentlichung Journaux, Baptiste Chauve, Thomas Montagnat, Maurine Tommasi, Andrea Barou, Fabrice Mainprice, David Gest, Léa Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
topic_facet |
article Verlagsveröffentlichung |
description |
Torsion experiments were performed in polycrystalline ice at high temperature (0.97 Tm) to reproduce the simple shear kinematics that are believed to dominate in ice streams and at the base of fast-flowing glaciers. As clearly documented more than 30 years ago, under simple shear ice develops a two-maxima c axis crystallographic preferred orientation (CPO), which evolves rapidly into a single cluster CPO with a c axis perpendicular to the shear plane. Dynamic recrystallization mechanisms that occur in both laboratory conditions and naturally deformed ice are likely candidates to explain the observed CPO evolution. In this study, we use electron backscatter diffraction (EBSD) and automatic ice texture analyzer (AITA) to characterize the mechanisms accommodating deformation, the stress and strain heterogeneities that form under torsion of an initially isotropic polycrystalline ice sample at high temperature, and the role of dynamic recrystallization in accommodating these heterogeneities. These analyses highlight an interlocking microstructure, which results from heterogeneity-driven serrated grain boundary migration, and sub-grain boundaries composed of dislocations with a [c]-component Burgers vector, indicating that strong local stress heterogeneity develops, in particular, close to grain boundaries, even at high temperature and high finite shear strain. Based on these observations, we propose that nucleation by bulging, assisted by sub-grain boundary formation and followed by grain growth, is a very likely candidate to explain the progressive disappearance of the c axis CPO cluster at low angle to the shear plane and the stability of the one normal to it. We therefore strongly support the development of new polycrystal plasticity models limiting dislocation slip on non-basal slip systems and allowing for efficient accommodation of strain incompatibilities by an association of bulging and formation of sub-grain boundaries with a significant [c] component. |
format |
Article in Journal/Newspaper |
author |
Journaux, Baptiste Chauve, Thomas Montagnat, Maurine Tommasi, Andrea Barou, Fabrice Mainprice, David Gest, Léa |
author_facet |
Journaux, Baptiste Chauve, Thomas Montagnat, Maurine Tommasi, Andrea Barou, Fabrice Mainprice, David Gest, Léa |
author_sort |
Journaux, Baptiste |
title |
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
title_short |
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
title_full |
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
title_fullStr |
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
title_full_unstemmed |
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
title_sort |
recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-1495-2019 https://noa.gwlb.de/receive/cop_mods_00002167 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00002125/tc-13-1495-2019.pdf https://tc.copernicus.org/articles/13/1495/2019/tc-13-1495-2019.pdf |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_relation |
The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-13-1495-2019 https://noa.gwlb.de/receive/cop_mods_00002167 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00002125/tc-13-1495-2019.pdf https://tc.copernicus.org/articles/13/1495/2019/tc-13-1495-2019.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-13-1495-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
5 |
container_start_page |
1495 |
op_container_end_page |
1511 |
_version_ |
1766216725221605376 |