Theoretical and experimental density of (U, Gd)O sub(2) and (U, Er)O sub(2)

• Published in: Atomic energy (New York, N.Y.) Vol. 113; no. 6; pp. 429 - 434
• Main Authors: Fedotov, A V, Mikheev, EN, Lysikov, A V, Novikov, V V
• Format: Journal Article
• Language: English
• Published: 01.04.2013
• Subjects: Density; Exact solutions; Mathematical analysis; Nuclear fuels; Oxides; Rare earth compounds; Solid solutions; Theoretical density
• ISSN: 1063-4258; 1573-8205
• DOI: 10.1007/s10512-013-9657-3

An analytical expression is obtained for calculating the theoretical density of a stoichiometric, equilibrium, solid solution of the type U sub(1-y)R sub( y)O sub(2) for uranium-gadolinium and uranium-erbium oxide fuel with different initial Gd sub(2)O sub(3) or Er sub(2)O sub(3) content. It is shown that the theoretical density of oxide fuel, containing a rare-earth oxide of the type R sub(2)O sub(3), determined on the basis of the x-ray density is 0.03 g/cm super(3) higher and 0.02 g/cm super(3) lower than the computed density of (U, Gd)O sub(2) and (U, Er)O sub(2), respectively. It is found that the density of sintered uranium-gadolinium oxide pellets with an equilibrium solid solution of the type (U, Gd)O sub(2) is 96-98% with initial Gd sub(2)O sub(3) mass fraction to 3.35% of the theoretical value and 98-99% with 5% and higher.