Patent Number: 
Section: claims

1. A process for the manufacture of a dense material containing uranium dioxide UO2, the process comprising:introducing a plurality of powders each including uranium dioxide UO2, into a vibrating grinder, at least two of the powders provided by, respectively, a wet route and a dry route, the at least two powders having different crystallite agglomeration and aggregation degrees, each of the powders having a specific surface area within about 10 m2/g of each other powder;shaking the powders with the vibrating grinder so as to form a particulate material lacking agglomerates and aggregates, the shaking including breaking up agglomerates and aggregates in the powders without at the same time breaking up crystallites in the powders, the shaking destroying substantially all agglomerates and aggregates in the powders;introducing the particulate material into a mould;applying a shaping stress to the particulate material so as to obtain a compacted material; andsintering the compacted material so as to obtain the dense material. 2. The process according to claim 1, wherein at least one of the powders contains at least one oxide chosen from the group consisting of uranium oxide U3O8, uranium oxide U3O7, plutonium oxide PuO2, and thorium oxide ThO2. 3. The process according to claim 1, wherein at least one of the powders contains at least one additive chosen from the group consisting of gadolinium oxide Gd2O3, erbium oxide Er2O3, a pore forming substance, a lubricant, and a sintering promoter. 4. The process according to claim, 1 wherein the shaking is carried out over at least a duration so as to form a particulate material having a substantially constant sinterability, compressibility and sinterability of the particulate material having values independent from the amount of agglomerates and/or aggregates contained in each of the powders. 5. The process according to claims 1, wherein the shaking is carried out by the grinder so as to increase the compressibility of the particulate material up to a substantially constant value, while sinterability remains substantially constant. 6. The process according to claim 1, wherein the applying the shaping stress is carried out under a stress ranging from about 200 to 1200 MPa. 7. The process according to claim 1, wherein each powder has a specific surface area within about 2 to 5 m2/g of each other powder.