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Crystal Structure of the ZrO Phase at Zirconium/Zirconium Oxide Interfaces.

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.

SUBMITTER: Nicholls RJ

PROVIDER: S-EPMC4393322 | biostudies-other | 2015 Feb

REPOSITORIES: biostudies-other

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Crystal Structure of the ZrO Phase at Zirconium/Zirconium Oxide Interfaces.

Nicholls Rebecca J RJ Ni Na N Lozano-Perez Sergio S London Andrew A McComb David W DW Nellist Peter D PD Grovenor Chris Rm CR Pickard Chris J CJ Yates Jonathan R JR

Advanced engineering materials 20140627 2

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 ...[more]

PMID: 25892957

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