The effect of pressure on hydrogen solubility in Zircaloy-4
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
The effect of pressure on the room temperature solubility of hydrogen in
Zircaloy-4 was examined using synchrotron X-ray diffraction on small ground
flake samples in a diamond anvil cell at pressures up to 20.9 GPa. Different
combinations of hydrogen level/state in the sample and of pressure transmitting
medium were examined; in all three cases examined, it could be concluded that
pressure resulted in the dissolution of d hydrides and that interstitial
hydrogen retards the formation of w Zr. A pressure of around 9 GPa was required
to halve the hydride fraction. These results imply that the effect of pressure
is thermodynamically analogous to that of increasing temperature, but that the
effect is small. The results are consistent with the volume per Zr atom of the
a, d and w phases, with the bulk moduli of a and d, and with previous
measurements of the hydrogen site molar volumes in the a and d phases. The
results are interpreted in terms of their implication for our understanding of
the driving forces for hydride precipitation at crack tips, which are in a
region of hydrostatic tensile stress on the order of 1.5 GPa.
Zircaloy-4 was examined using synchrotron X-ray diffraction on small ground
flake samples in a diamond anvil cell at pressures up to 20.9 GPa. Different
combinations of hydrogen level/state in the sample and of pressure transmitting
medium were examined; in all three cases examined, it could be concluded that
pressure resulted in the dissolution of d hydrides and that interstitial
hydrogen retards the formation of w Zr. A pressure of around 9 GPa was required
to halve the hydride fraction. These results imply that the effect of pressure
is thermodynamically analogous to that of increasing temperature, but that the
effect is small. The results are consistent with the volume per Zr atom of the
a, d and w phases, with the bulk moduli of a and d, and with previous
measurements of the hydrogen site molar volumes in the a and d phases. The
results are interpreted in terms of their implication for our understanding of
the driving forces for hydride precipitation at crack tips, which are in a
region of hydrostatic tensile stress on the order of 1.5 GPa.
Date Issued
2019-07-11
Date Acceptance
2019-07-11
Citation
Journal of Nuclear Materials, 2019, 524, pp.256-262
ISSN
0022-3115
Publisher
Elsevier
Start Page
256
End Page
262
Journal / Book Title
Journal of Nuclear Materials
Volume
524
Copyright Statement
© 2019 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Identifier
http://arxiv.org/abs/1806.09657v3
Grant Number
EP/H004882/1
Subjects
cond-mat.mtrl-sci
cond-mat.mtrl-sci
Notes
Updated in response to reviewer comments; results identical but discussion elaborated on some points. Accepted for publication in J. Nuclear Materials, 11 Jul 2019
Publication Status
Published online
Date Publish Online
2019-07-11