The main objective of this master thesis was assessing and evaluating the production of mixed U-Zr nitride fuel powders directly from metallic U-Zr binary alloys, instead of using separate nitride powders. Another secondary objective, if the main one was fulfilled at all, was assessing if it is easier to get the two nitrides in solid solution when obtained from the alloyed materials than when mixed from two nitride powders. Both objectives have been fulfilled by the experiments performed, and they are covered through the pages of this document. Mixed powders can indeed be produced directly from alloys. Therefore, when this procedure is used, many troublesome operations that involve the handling of radioactive and very atmosphere sensitive powders are omitted, which makes the job at the nuclear fuel production laboratories much easier. In addition, at least in one occasion, the mixed powder produced after the synthesis had the two nitrides forming solid solution. This very promising feature could be considerably helpful for the pressing and sintering of pellets if the solid solution from the powder was not affected by those processes. Very long diffusion controlled processes that need heat treatment at very high temperatures could be avoided if the solid solution lasted after sintering the pellets from the synthesized powders.

Outgoing