Atom Probe Tomography of Simulated Fission Product Segregation in CeO(2)

To improve the performance of nuclear fuel, one must understand the irradiation induced defects that lead to the decrease in fuel performance at an atomic scale. Irradiation induced defects, specifically fission gas bubble formation and nucleation, fission product segregation to grain boundaries and clustering, are of interest in this investigation. Characterization techniques, like atom probe tomography (APT) provides the capability to spatially resolve these features at an atomic scale. This study investigates the segregation behavior of fission products (Xenon and Lanthanum) in surrogate nuclear fuel material (CeO(2)) using APT. The Xe doped CeO(2) samples analyzed were ion implanted with 400 keV Xe+ ions and annealed to induce clustering. The La doped CeO(2) sample analyzed was irradiated with 1.8 MeV Kr+ ions to simulate irradiation induced diffusion of fission products. Commentary will also be provided on the advantages and challenges in using APT to study nuclear fuel.