Nuclear Fuel Rods Using Ceramic Clad Metal Pellets

Abstract

The invention aims at providing a nuclear fuel rod with ceramic cladding and metallic pellet. The nuclear fuel rod with ceramic cladding and metallic pellet has the advantages that the heat-conducting property of the nuclear fuel rod can be improved, the central temperature of the fuel pellet is lowered or the fuel power density is effectively improved, the fuel rod cladding mechanical property, corrosion resistance and radiation resistance are greatly improved, the breakage rate of the fuel rod is lowered, the discharge burnup of the fuel rod is remarkably increased and the fuel utilization rate is greatly improved; meanwhile, the fuel rod has good neutronics performance, and can be widely used in a fast reactor or a thermal reactor. The cladding of the nuclear fuel rod provided by the invention is a SiCf / SiC composite ceramic material cladding, the metallic fuel pellet adopts a U-Zr or U-Pu-Zr alloy fuel pellet; a gap between the cladding and the fuel pellet is filled with low-melting-point metal; and a lengthened air cavity is designed at the upper part of the fuel rod.

Description

technical field [0001] The invention relates to a fuel rod in the field of nuclear reactor engineering, which can be used as a core fuel rod of a fast neutron reactor or a thermal neutron reactor. Background technique [0002] Nuclear fuel rods are the basic unit for releasing energy in a nuclear reactor. A certain number of fuel rods are assembled through structural parts such as bases and grids to form fuel assemblies, and the nuclear reactor core is composed of these fuel assemblies. Nuclear fuel rods are generally composed of fuel pellets and cladding, and there is generally a certain gap between the pellets and the cladding. At the same time, there is still a cavity on the upper part of the fuel rod, which is used to accommodate the fission gas produced by the fuel rod during the long-term nuclear reaction. [0003] Fuel pellets are the actual exothermic nuclear fuel elements. The most common fuel pellets are UO formed by powder metallurgy and high temperature sinteri...

AI Technical Summary

Problems solved by technology

Although the above design increases the heat transfer capacity of the fuel rod by changing the structure of the fuel rod, increasing the heat transfer area, etc., it fails to fundamentally improve its heat conduction capacity, and the neutronics and mechanical properties of the cladding and fuel have not been improved. improve

In general, the thermal conductivity and mechanical properties of existing fuel rods are poor, and the cladding is prone to damage under high temperature and irradiation conditions

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