Rate control sintering of the uranium dioxide

Abstract

The application of rate controlled sintering (RCS) technique for fabricating oxide fuel pellets in industrial conditions is investigated. Green pellets of UO2 (with no additives) which underwent industrial-type compacting were sintered in reducing Ar - 8% H2 medium using dynamic and isothermal RCS modes with exposure at 1600 °C during 8 hours. Decreasing shrinkage rate resulted in growth of sintered density for the dynamic RCS mode. Opposite to the results of earlier works [1,2], decreasing heating rate did not result in reducing sintering rate. Isothermal mode allowed sintering rate to be maintained between 0.1- 0.15%/min. Temperature-time modes obtained using RCS are close to the operation mode of through-type furnace used for mass production.