Present status of MOX fuel fabrication technology and performance in Japan

The progress of MOX fuel fabrication technology in Japan has been reviewed. Based on the basic studies at the PFDF since 1966, the PFFF was constructed and started operation in 1972 to fabricate MOX fuels for Joyo and Fugen. More than 70 tons of MOX fuel has been fabricated to date. Improvements in fabrication processes and equipments have been accomplished to assure improved product uniformity, reduced radiation exposures and enhanced SNM safeguards. A new facility PFPF with completely automated fabrication process lines is being constructed to supply MOX fuels primarily to Monju and the demonstration ATR. In addition to the progress in fabrication technology, data for MOX fuels performance are being collected in wide ranges through the post-irradiation examination of fuels from Joyo, Fugen and various experiments in foreign and domestic test reactors. Experiments on MOX fuels for LWRs have been also conducted. All the data collected to date indicate satisfactory behaviors under irradiation in thermal and fast reactors. Current emphases in MOX fuel development program are placed on the development of long-life, low-cost fuels for FBRs and the improvement of burnup and load following capabilities in ATR fuels. (author)