Crystal Structure of the ZrO Phase at Zirconium/Zirconium Oxide Interfaces
Rebecca J Nicholls1, Na Ni1, Sergio Lozano-Perez1
1Dr. R. J. Nicholls, Dr. S. Lozano-Perez, A. London, Prof. P. D. Nellist, Prof. C. R. M. Grovenor, Dr. J. R. Yates, Department of Materials, University of Oxford Parks Road, Oxford, OX1 3PH, UK.
Abstract:
Zirconium-based alloys are used in water-cooled nuclear reactors for both nuclear fuel cladding and structural components. Under this harsh environment, the main factor limiting the service life of zirconium cladding, and hence fuel burn-up efficiency, is water corrosion. This oxidation process has recently been linked to the presence of a sub-oxide phase with well-defined composition but unknown structure at the metal-oxide interface. In this paper, the combination of first-principles materials modeling and high-resolution electron microscopy is used to identify the structure of this sub-oxide phase, bringing us a step closer to developing strategies to mitigate aqueous oxidation in Zr alloys and prolong the operational lifetime of commercial fuel cladding alloys.
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