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| Titel |
Preliminary 3D In-situ measurements of the texture evolution of strained H2O ice during annealing using neutron Laue diffractometry |
| VerfasserIn |
Baptiste Journaux, Maurine Montagnat, Thomas Chauve, Bachir Ouladdiaf, John Allibon |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250104287
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| Publikation (Nr.) |
 EGU/EGU2015-3706.pdf |
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| Zusammenfassung |
| Dynamic recrystallization (DRX) strongly affects the evolution of microstructure (grain size
and shape) and texture (crystal preferred orientation) in materials during deformation at high
temperature. Since texturing leads to anisotropic physical properties, predicting the effect of
DRX is essential for industrial applications, for interpreting geophysical data and
modeling geodynamic flows, and predicting ice sheet flow and climate evolution. A
large amount of literature is available related to metallurgy, geology or glaciology,
but there remains overall fundamental questions about the relationship between
nucleation, grain boundary migration and texture development at the microscopic
scale.
Previous measurements of DRX in ice were either conducted using 2D ex-situ
techniques such as AITA [1,2] or Electron Backscattering Diffraction (EBSD) [3],
or using 3D statistical ex-situ [4] or in-situ [5] techniques. Nevertheless, all these
techniques failed to observe at the scale of nucleation processes during DRX in full
3D.
Here we present a new approach using neutron Laue diffraction, which enable to perform
3D measurements of in-situ texture evolution of strained polycrystalline H2O ice (>2% at
266 K) during annealing at the microscopic scale. Thanks the CYCLOPS instrument [6]
(Institut Laue Langevin Grenoble, France) and the intrinsic low background of this setup,
preliminary observations enabled us to follow, in H2O ice, the evolution of serrated grain
boundaries, and kink-band during annealing. Our observations show a significant evolution of
the texture and internal misorientation over the course of few hours at an annealing
temperature of 268.5 K. In the contrary, ice kink-band structures seem to be very stable over
time at near melting temperatures. The same samples have been analyzed ex-situ using EBSD
for comparison.
These results represent a first step toward in-situ microscopic measurements of dynamic
recrystallization processes in ice during strain. This experiment has been conducted in the
frame of the ANR-funded DREAM project that focuses on the recrystallization processes in
anisotropic materials.
References
[1]ÂÂÂD. S. Russell-Head and C.J.L. Wilson., 2001, Journal of Glaciology, 24,
117-130.
[2]ÂÂÂWilson, C.J.L., Peternell, M., Piazolo, S., Luzin, V., 2014, Journal of
Structural Geology, Microdynamics of Ice, 61, 50-77.
[3]ÂÂÂM. Montagnat, T. Chauve, F. Barou, A. Tommasi, B. Beausir, C. Fressengeas.,
in prep.
[4]ÂÂÂT. H. Jacka and J. Li., 2000, In T. Hondoh, editor, Physics of Ice Core Records,
pages 83-102. Hokkaido University Press, Sapporo.
[5]ÂÂÂS. Piazolo, C. J. L. Wilson, V. Luzin, C. Brouzet, and M. Peternell., 2013,
Geochemistry, Geophysics, Geosystems, 14, 4185-4194.
[6]ÂÂÂB. Ouladdiaf et al., 2011, Journal of Applied Crystallography, 44, 392-397. |
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