Partition of soluble fission products between the grey phase, ZrO2 and uranium dioxide

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
The energies to remove fission products from UO2 or UO2+x and incorporate them into BaZrO3, SrZrO3 (grey phase constituent phases) and ZrO2 have been calculated using atomistic scale simulation. These energies provide the thermodynamic drive for partition of soluble fission products between UO2 or UO2+x and these secondary oxide constituents of the fuel system. Tetravalent cation partition into BaZrO3, SrZrO3 and ZrO2 was only preferable for species with smaller radii than Zr4+, regardless of uranium dioxide stoichiometry. Under stoichiometric conditions both the larger and the smaller trivalent cations were found to segregate to BaZrO3 but only the smaller fuel additive elements Cr3+ and Fe3+ segregate to SrZrO3. Partition from UO2+x was always unfavourable for trivalent cations. Additions of excess Cr3+ (as a fuel additive) are predicted make the partition into BaZrO3 and SrZrO3 more favourable from UO2 for the larger trivalent cations. Trivalent fission products with radii smaller than or equal to that of Sm3+ were identified to segregate into ZrO2 only from UO2. No segregation to SrO or BaO is predicted. © 2013, Elsevier B.V.
Fission products, Uranium dioxide, Oxides, Perovskite, Stoichiometry, Fuels
Cooper, M. W. D., Middleburgh, S. C., & Grimes, R. W. (2013). Partition of soluble fission products between the grey phase, ZrO2 and uranium dioxide. Journal of Nuclear Materials, 438(1-3), 238-245. doi:10.1016/j.jnucmat.2013.02.082