Segregation of xenon to dislocations and grain boundaries in uranium dioxide

Journal Article · Tue Nov 01 00:00:00 EDT 2011 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.84.174105· OSTI ID:21596911

Nerikar, P V; Casillas Trujillo, L A; Andersson, D A; Unal, C; Uberuaga, B P; Stanek, C R ^[1]; Parfitt, D C; Grimes, R W ^[2]; Sinnott, S B ^[3]

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1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2. Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom)
3. Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)

It is well known that Xe, being insoluble in UO{sub 2}, segregates to dislocations and grain boundaries (GBs), where bubbles may form resulting in fuel swelling. Less well known is how sensitive this segregation is to the structure of the dislocation or GB. In this work we employ pair potential calculations to examine Xe segregation to dislocations (edge and screw) and several representative grain boundaries ({Sigma}5 tilt, {Sigma}5 twist, and random). Our calculations predict that the segregation trend depends significantly on the type of dislocation or GB. In particular we find that Xe prefers to segregate strongly to the random boundary as compared to the other two boundaries and to the screw dislocation rather than the edge. Furthermore, we observe that neither the volumetric strain nor the electrostatic potential of a site can be used to predict its segregation characteristics. These differences in segregation characteristics are expected to have important consequences for the retention and release of Xe in nuclear fuels. Finally, our results offer general insights into how atomic structure of extended defects influence species segregation.

• OSTI ID: 21596911
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 84, Issue 17; Other Information: DOI: 10.1103/PhysRevB.84.174105; (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BUBBLES
DEFECTS
GRAIN BOUNDARIES
NUCLEAR FUELS
SCREW DISLOCATIONS
SEGREGATION
STRAINS
URANIUM DIOXIDE
XENON
ACTINIDE COMPOUNDS
CHALCOGENIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
ELEMENTS
ENERGY SOURCES
FLUIDS
FUELS
GASES
LINE DEFECTS
MATERIALS
MICROSTRUCTURE
NONMETALS
OXIDES
OXYGEN COMPOUNDS
RARE GASES
REACTOR MATERIALS
URANIUM COMPOUNDS
URANIUM OXIDES