Determination of Gd concentration profile in UO2?Gd2O3 fuel pellets

D. TOBIA; E. L. WINKLER; J. MILANO; A. BUTERA; R. KEMPF; L. BIANCHI; F. KAUFMANN

JOURNAL OF NUCLEAR MATERIALS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 451 p. 207 - 210

0022-3115

A transversal mapping of the Gd concentration was measured in UO2-Gd2O3 nuclear fuel pellets by electron paramagnetic resonance spectroscopy (EPR). The quantification was made from the comparison with a Gd2O3 reference sample. The nominal concentration in the pellets is UO2: 7.5 % Gd2O3. A concentration gradient was found, which indicates that the Gd2O3 amount diminishes towards the edges of the pellets. The concentration varies from (9.3±0.5)% in the center to (5.8±0.3)% in one of the edges. The method was found to be particularly suitable for the precise mapping of the distribution of Gd3+ ions in the UO2 matrix.