The effect of grain boundaries and second-phase particles on hydride precipitation in zirconium alloys
File(s)SEC_MP_MRSAdvances2017_Accepted_pdf.pdf (524.47 KB)
Accepted version
Author(s)
El Chamaa, Said
Patel, mitesh
Davies, catrin
Wenman, MR
Type
Journal Article
Abstract
Understanding the precipitation of brittle hydride phases is crucial in establishing a failure criterion for various zirconium alloy nuclear fuel cladding. Accordingly, it is important to quantify the sensitivity of hydride precipitation to the component microstructure. This experimental investigation focuses on two microstructural characteristics and their role as hydride nucleation sites: The grain size and the alloy chemical composition. Samples of commercially pure zirconium (Zr-702) and Zircaloy-4, each with a wide range of grain sizes, were hydrided to 100 ppm and micrographs of the hydride distribution were optically analyzed for inter-granular and intra-granular precipitate sites. For most grain sizes, it was found that a significantly lower fraction of the precipitated hydrides nucleated at grain boundaries in Zircaloy-4 than in Zr-702, suggesting that a higher SPP content encourages the formation of intra-granular hydrides. Moreover, this effect became more prominent as the grain size increased; large-grain specimens contained a higher fraction of intra-granular hydrides than small-grain specimens of both Zr-702 and Zircaloy-4, highlighting the potency of grain boundaries as nucleation sites and how SPPs can influence the hydride distribution profile.
Date Issued
2018-01-28
Date Acceptance
2018-01-18
Citation
MRS Advances, 2018, 3 (31), pp.1749-1754
ISSN
2059-8521
Publisher
Cambridge University Press
Start Page
1749
End Page
1754
Journal / Book Title
MRS Advances
Volume
3
Issue
31
Copyright Statement
© Materials Research Society 2018. This paper has been accepted for publication and will appear in a revised form, subsequent to peer-review and/or editorial input by Cambridge University Press.
Sponsor
Rolls-Royce Plc
Grant Number
See further info
Subjects
Science & Technology
Technology
Materials Science, Multidisciplinary
Materials Science
ZIRCALOY-4
HYDROGEN
Publication Status
Published
Date Publish Online
2018-01-28