Metallic fission product release from failed coated fuel particles. ICF-51H capsule irradiation test

ICF-51H capsule irradiation test was performed to study the release behavior of metallic fission products from failed coated fuel particles. Three kinds of coated fuel particles of artificially failed particles simulating through coating failure, SiC-defective particles, and intact particles were irradiated in the Japan Research Reactor-2 at about 1600K to about 2%FIMA. In the postirradiation examinations, γ-ray spectrometry of the particles was carried out, together with visual examination, X-ray microradiography, and ceramography. It was found that 144Ce, 106Ru, and 125Sb were retained in the SiC-defective particles as in the intact particles, whereas inventories of 137Cs, 134Cs, and 154Eu in the SiC-defective particles were smaller than those in the intact particles. All measured inventories in the artificially failed particles were found to be smaller than those in the intact particles. The release behavior of cesium from model particles was analyzed with FORNAX code and was compared with the experimental results. (author)