Comparison of two powder conditioning methods to improve UO2 powder flowability for press die filling

In the nuclear industry, mixed oxide fuel pellets are manufactured by powder metallurgy process. This work aims at improving physical and flow properties of powders in order to obtain a reproducible die filling produce homogeneous dense after sintering. The studied was grinded mixture UO2 sintered scraps (recycled). Two conditioning methods were tested compared: V-blender an oscillating rotating OscilloWitt-Lab sieve mill associated Turbula mixer. first method consisted three main steps realized V-blender: deagglomeration step with intensifier bar, stirring lubrication step. second also steps: sieving OscilloWitt-Lab, followed Different bar speeds on different mesh sizes studied. Particle size, morphology, mechanical characterized each only slightly improved flowability compared initial powder. speed had negligible impact characteristics mixer allowed marked improvement size significant characteristics. Indeed, using 250 μm resulted most favorable properties. Therefore, it seems be promising as well pellets.