Production and investigation of thorium-containing fuel compositions

A technology has been developed for obtaining fuel tablets with the compositions (U, Th)O2, (U, Th, Ca)O2, and (U, Th)O2+MgO by combined precipitation of uranium, thorium, magnesium, or calcium components from inert solutions, followed by heat treatment of the powders, compression into pellets, and sintering of the pellets. Work on optimizing the technological processes for obtaining fuel pellets so as to obtain good pellet quality was performed. The effect of the properties of the precipitates and powders, fabricated using different technological regimes on the properties of the finished objects was studied. The work includes detailed investigations of powders (x-ray phase analysis, electron-microscopic investigation) and sintered fuel tablets (change in the geometric dimensions as a result of sintering, determination of the density, and study of the microstructure).