6 results about "Uranium nitride" patented technology

The invention belongs to the field of nuclear materials, and particularly relates to a nuclear fuel and a preparation method thereof and a reactor, the nuclear fuel comprises a nitride matrix and an MAX phase material distributed in the nitride matrix; the chemical formula of the MAX phase material is Mn + 1AXn, M is selected from at least one of Ti and Cr, A is selected from at least one of Si and Al, X is selected from C, and n is 1 or 2. According to the nuclear fuel disclosed by the invention, the MAX phase material is introduced into the nitride matrix, and a corrosion-resistant oxide layer is generated in situ by utilizing the MAX phase material to block water permeation, so that the nuclear fuel has the properties of high thermal conductivity, relatively strong water corrosion resistance, steam oxidation resistance and radiation resistance, and can be applied to a light water reactor; the application risk of the existing uranium nitride fuel in the light-water reactor is reduced, and the safety and economy of the reactor are improved.

The embodiment of the application relates to the technical field of binary compounds of nitrogen and metal, and particularly relates to a preparation method of uranium nitride particle fuel and the uranium nitride particle fuel. The application provides a preparation method of uranium nitride particle fuel, which comprises the following steps: treating molybdenum-niobium metal powder, so that the molybdenum-niobium alloy powder is coated with a zirconium coating; preparing uranium oxide particles with uniform particle size; reacting the uranium oxide particles with ammonia to obtain uranium nitride particles; mixing the molybdenum-niobium alloy powder and the uranium nitride particles, so that the two are uniformly distributed in the obtained mixture; sintering the mixture, so that the obtained compact is formed into a dense structure; and forming the compact to obtain the uranium nitride particle fuel. The application also provides a uranium nitride particle fuel. The fuel prepared by the method of the application can improve the damage resistance of the fuel under strong radiation conditions, reduce the irradiation swelling of the fuel, ensure the low release of the fuel, and fully meet the application requirements in space nuclear reactors.

The invention belongs to the technical field of fuel microsphere manufacturing, and provides UN-ThN composite fuel microspheres and a preparation method thereof.The method comprises the steps that firstly, uranium nitride microspheres are prepared, a fluidized bed based on chemical vapor deposition is adopted, a gas conveying system is arranged, and the uranium nitride microspheres are added into the fluidized bed; introducing thorium source gas and nitrogen source gas through a gas conveying system, and carrying out chemical reaction on the introduced precursor gas on the surfaces of the UN microspheres and generating a ThN coating, so as to prepare the UN-ThN composite fuel. The preparation method disclosed by the invention is simple and controllable in process, and an effective way is provided for realizing preparation of the high-performance composite fuel microspheres and value-added utilization of thorium resources.

The application discloses a preparation method of uranium nitride spherical particles, and comprises the following steps: mixing a carbon source and a solution to prepare gel particles; the carbon source comprises diamond powder; the gel particles are pretreated and subjected to carbonthermal reduction and nitriding treatment to obtain the uranium nitride spherical particles. The preparation method can effectively control the C / U molar ratio, and the prepared uranium nitride spherical particles have the advantages of compact structure, smooth surface and high purity.

The invention relates to the technical field of UN nuclear fuel, and particularly discloses a high-density single-phase UN fuel microsphere and a preparation method thereof in order to solve the problem that existing uranium nitride fuel microsphere crystal structure phase composition is relatively complex, the preparation method comprises the following steps: S1, taking a uranyl nitrate solution, adding urea, urotropine and a carbon source, and mixing to prepare carbon-containing sol; s2, dispersing the carbon-containing sol into an organic solvent through a dispersion pore plate to form carbon-containing gel balls, and then washing, drying and calcining to obtain UO3-C dry calcined balls; s3, the UO3-C dry calcined pellets are sequentially subjected to carbon thermal reduction and nitriding sintering treatment, and the single-phase UN fuel microspheres are obtained. In the stage of preparing the uranyl nitrate solution, a special carbon source is added, so that the distribution uniformity of the carbon source in the UO3-C dry calcined ball is ensured; and in the later conversion processes of carbon thermal reduction, nitridation and the like, reducing gases with different proportions are introduced, and finally, the UN fuel microspheres composed of high-density and single-phase UN components are prepared.

Computer system determines a particle design for a multilayer nuclear fuel particle. A first particle design includes a first set of values for a plurality of design variables corresponding to the multilayer nuclear fuel particle. Using the first set of values as inputs, the computer system (i) causes execution of a thermal-mechanical model and obtains a first predicted outcome; (ii) causes execution of a neutronics model and obtains a second predicted outcome; (iii) determines an aggregate residual for the first particle design based on the first and second predicted outcomes, and (iv) identifies a second particle design for the multilayer nuclear fuel particle. The second particle design includes a second set of values corresponding to the plurality of design variables. The computer system uses the second set of values and repeats steps (i) through (iv) identifying an updated particle design, to obtain an optimized particle design for the multilayer particle.