Open AccessFISSION-GAS-RELEASE FROM UO$sub 2$, INTERIM REPORT NO. 1
Author(s) -
J.G. Morgan,
M.T. Morgan,
M.F. Osborne
Publication year - 1960
Language(s) - English
Resource type - Reports
DOI - 10.2172/4068895
Subject(s) - pellets , stoichiometry , radiochemistry , fission , fission products , impurity , uranium dioxide , materials science , uranium , analytical chemistry (journal) , irradiation , mass fraction , chemistry , nuclear chemistry , neutron , nuclear physics , metallurgy , chromatography , physics , organic chemistry , composite material
The evolution of fission products from UO/sub 2/ during irradiation at high temperatures is of primary interest to the Gas-cooled Reactor Project. Fuel tests consisting of UO/sub 2/ pellets encapsulated in Inconel or stainless steel were irradiated in the LITR, ORR, and ETR. The capsules were pierced in hot cells, and the gases collected in evacuated systems. Fractions of this gas, of suitable activity for counting, were taken and then analyzed by gamma spectrometry. Larger fractions of gas were analyzed by mass spectrometry. Percentage of gas release varied widely, increasing with temperature, impurity content, oxygen-to-uranium ratio of the UO/sub 2/, and decreasing with bulk density. For high density, stoichiometric UO/sub 2/, the gas release was generally less than 3% up to a temperature of about 2800 deg F, about which it was greatly accelerated. Fuel burn-ups of up to 22,000 Mwd/MT were obtained. Maximum measured central fuel temperatures of 3150 deg F were reached. The lower- density nonstoichiometric UO/sub 2/ released greater amounts of fission gas, particularly Kr/sup 85/. (auth