Xenon migration in UO2: A SIMS study

The knowledge of the gas fission product behavior is mandatory when assessing the performance of the LWR fuel. In this study, Xenon is implanted at two fluences (1015 and 1016 at.cm−2) in two batches of UO2 sintered pellets differing only from the grain size (7 μm and 22 μm). The evolution of Xenon depth profiles versus thermal treatments (1673 K and 1873 K) is analyzed by SIMS. This technique allows measuring diffusion coefficients without applying the Booth model as it is done for most of the previous studies. Our results show that, for the low fluence, the diffusion coefficient is much lower than pointed out in the literature.