The Sintering Mixed Powders Behavior of Triuranium Octoxide in Uranium Dioxide

The main aim of this research was to study the sintering behavior in hydrogen atmosphere of mixed powders of triuranium octoxide (U3O8) powder in dioxide uranium (UO2) powders. By cold pressing the green pellets of mixed powders of triuranium octoxide in hyper stoichiometric uranium dioxide has density over 40 % UO2 theoretical density (TD). The sintered pellets had a height diameter ratio (H / D) over one and oxygen uranium ratio (O/U) near stoichiometry of uranium dioxide (UO2). The densities of sintered pellets were up to 97% of uranium dioxide theoretical density. The proposed treatment of sintering are function of green pellets density. Increasing the proportion of triuranium octoxide leads to a decrease in the density of the sinter pellets. The pellets made by 100 % of triuranium octoxide not resist to proposed sintering treatment. The metallographic analysis show uniform grains for sinter pellets made by the 30 % mixture of triuranium octoxide in uranium dioxide. This UO2 sinter pellets are without surface defects.