Plasticity of zirconium hydrides: a coupled edge and screw discrete dislocation model
File(s)
Accepted version
Author(s)
Reali, Luca
Wenman, Mark R
Sutton, Adrian P
Balint, Daniel S
Type
Journal Article
Abstract
Understanding the plastic behaviour of thin zirconium hydrides is important for its implications on crack nucleation in the Zirconium alloy cladding used in fission reactors. Microvoids originate at fractured hydrides, and their coalescence may lead to the failure of the component. In this work, an innovative discrete dislocation framework is presented together with the preliminary results. The aim is to develop a model that is significantly faster than existing 3D formulations, to make it possible to run a statistical analysis on a simulated microstructure. This comes with limitations, which are discussed together with the planned developments. The model combines two planar and orthogonal simulations. In one only edge, in the other only screw dislocations are allowed, thereby describing all sides of a dislocation loop approximated as a rectangle. The two families of dislocations interact via their elastic stress, and this coupling proved to be important and significantly enhanced the dislocation density. The proposed model enables us to implement a 3D stress analysis of the hydrides. The simulations show that the most critical scenario is when neighbouring slip planes become populated with opposite-signed dislocations. This was observed both in the edge and in the screw case, and was reflected in the principal stress calculated by combining the two. It was also observed that the degree of permeability of the interface to dislocation crossing is inversely correlated to the stress inside the hydride and to the dislocation source activation.
Date Issued
2021-02
Date Acceptance
2020-11-03
Citation
Journal of the Mechanics and Physics of Solids, 2021, 147
ISSN
0022-5096
Publisher
Elsevier
Journal / Book Title
Journal of the Mechanics and Physics of Solids
Volume
147
Copyright Statement
Copyright © Elsevier Ltd. All rights reserved. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/
Identifier
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000612236400012&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
Subjects
Computational model
Coupled discrete dislocation plasticity
DEFORMATION
DELTA-HYDRIDE
EMBRITTLEMENT
HOOP MECHANICAL-PROPERTIES
Hydrides
Materials Science
Materials Science, Multidisciplinary
Mechanics
Physical Sciences
Physics
Physics, Condensed Matter
PRECIPITATION
RATE SENSITIVITY
RECRYSTALLIZED ZIRCALOYS
Science & Technology
Technology
TITANIUM
WATER REACTOR PWR
ZIRCALOY CLADDING TUBES
Zirconium alloys
Publication Status
Published
Article Number
104219
Date Publish Online
2020-11-12