Lattice location of fission products in UO(2) single crystals
Heavy fission product ions (Te, Xe, Cs) were implanted in UO(2) single crystals at 50 keV to high fluences between 5 x 1.0 E15 and 1 x 1.0 E17 ions/cm2. The implantations were performed at 77 K (Te, Xe) and 293 K (all three elements). The crystals were subsequently analysed in situ using the Rutherford backscattering channelling technique. All implants exhibited a large (apparent) substitutional fraction SF = 50/70% when implanted at 293 K. In contrast, SF = 0 for the implantations at 77 K. The annealing behaviour was also studied. For the crystals implanted at 293 K, the release of impurity atoms (Te, Cs) sets in at temperatures above 750 K and is clearly correlated with radiation damage recovery. Xe-release starts above approximately 1300 K. The release of Te implanted at 77 K begins at 400 K and is nearly completed at 600 K. In this temperature range, no changes in the damage distribution were noticed. These results give the first indication of coherent precipitation of solid rare gases and volatiles in UO(2).
Bibliographic Reference: Paper presented: 6th International Conference on Radiation Effects in Insulators, Weimar (DE), June 24-28, 1991
Availability: Available from (1) as Paper EN 36292 ORA
Record Number: 199111129 / Last updated on: 1994-12-02
Original language: en
Available languages: en