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Characterization of the Penetration Mechanisms of Water into Polycrystalline UO2

Published online by Cambridge University Press:  01 February 2011

Ilaria Marchetti
Affiliation:
Fabio Belloni
Affiliation:
[email protected], European Commission, JRC - Institute for Transuranium Elements (ITU), Karlsruhe, Germany
Jerome Himbert
Affiliation:
[email protected], European Commission, JRC - Institute for Transuranium Elements (ITU), Karlsruhe, Germany
Paul Carbol
Affiliation:
[email protected], European Commission, JRC - Institute for Transuranium Elements (ITU), Karlsruhe, Germany
Thomas Fanghänel
Affiliation:
[email protected], European Commission, JRC - Institute for Transuranium Elements (ITU), Karlsruhe, Germany
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Abstract

Following containment failure in the scenario of geological disposal of spent nuclear fuel, the penetration rate of groundwater into the UO2 matrix could cause a rapid increase of the fraction of inventory becoming available for prompt dissolution. In this respect, oxygen and water diffusion mechanisms are key issues to investigate. In this work, secondary-ion-mass-spectrometry (SIMS) depth profiling has been applied to characterize a polycrystalline UO2 pellet exposed to 18O-labelled water at room temperature. 18O depth profiling up to 25 μm beneath the pellet surface clearly indicates a combination of oxygen diffusion into the UO2 lattice and water diffusion along grain boundaries, behaving as high diffusivity paths. The lattice diffusion coefficient of oxygen, DL , and the quantity δDB – product of the grain boundary width, δ, and the grain boundary diffusion coefficient of water, DB – have been measured, resulting in DL = (2.5 ± 0.1) × 10-24 m2 s-1 and δDB = (7.5 ± 0.3) × 10-24 m3 s-1.

Type
Research Article
Copyright
Copyright © Materials Research Society 2010

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References

1 Lay, K. W. J. Am. Ceram. Soc. 53, 369 (1970).Google Scholar
2 Bittel, J.T. Sjodahl, L.H. and White, J.F. J. Am. Ceram. Soc. 52, 446 (1969).Google Scholar
3 Belle, J. J. Nucl. Mater. 30, 3 (1969).Google Scholar
4 SKI Technical Report 96:36, Swedish Nuclear Power Inspectorate (Stockholm, 1996) pp 265266.Google Scholar
5 Cranck, J. The Mathematics of Diffusion (Oxford University Press, 1975) pp. 2843.Google Scholar
6 Levine, H.S. and MacCallum, C.J. J. Appl. Phys. 31, 595 (1960).Google Scholar
7 Shewmon, P.G. Diffusion in Solids (The Minerals Metals and Materials Society, 1989) pp. 189205.Google Scholar
8 Kaur, I. Mishin, Y. and Gust, W. Fundamentals of Grain and Interphase Boundary Diffusion (Wiley and Sons, 1995) pp. 100104.Google Scholar
9 Kubo, T. Ishimoto, S. and Koyama, T. J. Nucl. Sci. Technol. 30, 664 (1993).Google Scholar
10 Neck, V. and Kim, J.I. Radiochim. Acta 89, 1 (2001).Google Scholar