Disclosed are a sintered nuclear fuel pellet, a fuel rod, a fuel assembly and a method of manufacturing the nuclear fuel pellet. The pellet comprises a matrix of UO.sub.2 and particles dispersed in the matrix. The particles comprises a uranium-containing material. Each of the particles is encapsulated by a metallic coating. The uranium-containing material has a uranium density that is higher than the uranium density of UO.sub.2. The metallic coating consists of at least one metal chosen from the group of Mo, W, Cr, V and Nb.

A Thorium fuel rod assembly is disclosed that includes first and second support elements and a number of Thorium fuel rods positioned between support elements. Each of the Thorium fuel rod includes an outer fuel element containing a solid Thorium an inner core element containing Beryllium that is positioned within an interior cavity defined by the outer fuel element. In an exemplary disclosure, the inner core element also defines an inner cavity such that a beam of high energy particles may be directed into the inner cavity of the inner core element to impinge upon a Beryllium nucleus within the inner core element to produce a (p, n) reaction resulting in the emission of a neutron, where the emitted neutron may interact with a Thorium nucleus in the outer fuel element to cause the Thorium nucleus to fission.

The present disclosure provides a fuel rod and a fuel assembly, in which the fuel rod includes a first uranium pellet, a gadolinium pellet and a second uranium pellet, and the first uranium pellet, the gadolinium pellet and the second uranium pellet are each of a cylindrical shape, an end face of an end of the gadolinium pellet is connected to an end face of an end of the first uranium pellet, and an end face of an opposite end of the gadolinium pellet is connected to an end face of an end of the second uranium pellet, and the difference between an enrichment of the gadolinium pellet and an enrichment of the first uranium pellet is less than or equal to 0.5%, and the difference between an enrichment of the gadolinium pellet and an enrichment of the second uranium pellet is less than or equal to 0.5%.

The present disclosure provides a fuel rod and a fuel assembly, in which the fuel rod includes a first uranium pellet, a gadolinium pellet and a second uranium pellet, and the first uranium pellet, the gadolinium pellet and the second uranium pellet are each of a cylindrical shape, an end face of an end of the gadolinium pellet is connected to an end face of an end of the first uranium pellet, and an end face of an opposite end of the gadolinium pellet is connected to an end face of an end of the second uranium pellet, and the difference between an enrichment of the gadolinium pellet and an enrichment of the first uranium pellet is less than or equal to 0.5%, and the difference between an enrichment of the gadolinium pellet and an enrichment of the second uranium pellet is less than or equal to 0.5%.

In one embodiment, an alloy includes: Zr; Fe; Cu; Ta in an amount from about 1 wt % to about 3 wt %; and one or more optional constituents selected from: Ti, Be, and Nb; and wherein the alloy comprises a ductile phase and a nanoprecipitate hard phase. According to another embodiment, a method of forming an inert matrix nuclear fuel includes: packing a hollow structure with fuel pellets and alloy precursor pellets; heating the fuel pellets and the alloy precursor pellets to at least a melting temperature of an alloy to be formed by melting the alloy precursor pellets; and solidifying the alloy into a matrix surrounding the fuel pellets. The alloy precursor pellets independently comprise: Zr; Fe; Cu; Ta present in an amount from about 1 to about 3 wt %; and one or more optional alloy constituents selected from: Ti, Be, and Nb.

In one embodiment, an alloy includes: Zr; Fe; Cu; Ta in an amount from about 1 wt % to about 3 wt %; and one or more optional constituents selected from: Ti, Be, and Nb; and wherein the alloy comprises a ductile phase and a nanoprecipitate hard phase. According to another embodiment, a method of forming an inert matrix nuclear fuel includes: packing a hollow structure with fuel pellets and alloy precursor pellets; heating the fuel pellets and the alloy precursor pellets to at least a melting temperature of an alloy to be formed by melting the alloy precursor pellets; and solidifying the alloy into a matrix surrounding the fuel pellets. The alloy precursor pellets independently comprise: Zr; Fe; Cu; Ta present in an amount from about 1 to about 3 wt %; and one or more optional alloy constituents selected from: Ti, Be, and Nb.

Provided are a nuclear fuel rod for fast reactors that includes a metallic fuel slug coated with a protective coating layer and a fabrication method thereof. The nuclear fuel rod for fast reactors that includes a surface treated metallic fuel slug and a cladding tube according to the present invention has an excellent effect of stabilizing components of the metallic fuel slug and fission products or impurities, because the interdiffusion between the metallic fuel slug and the cladding tube does not occur. Also, since the uniform coating on the surface of the metallic fuel slug may be facilitated and fabrication costs may be significantly reduced in comparison to a typical technique of using a functional material for preventing the interdiffusion at an inner surface of the cladding tube, it may be suitable for fabricating the nuclear fuel rod for fast reactors.

Provided are a nuclear fuel rod for fast reactors that includes a metallic fuel slug coated with a protective coating layer and a fabrication method thereof. The nuclear fuel rod for fast reactors that includes a surface treated metallic fuel slug and a cladding tube according to the present invention has an excellent effect of stabilizing components of the metallic fuel slug and fission products or impurities, because the interdiffusion between the metallic fuel slug and the cladding tube does not occur. Also, since the uniform coating on the surface of the metallic fuel slug may be facilitated and fabrication costs may be significantly reduced in comparison to a typical technique of using a functional material for preventing the interdiffusion at an inner surface of the cladding tube, it may be suitable for fabricating the nuclear fuel rod for fast reactors.

The invention relates generally to uranium fuel in a nuclear reactor and, more particularly, the inclusion of a fuel additive component to the bulk fuel material. The fuel additive component is selected and provided in an amount such that it is effective to improve one or more properties of the bulk fuel material. The fuel additive component has a grain size that is less than the grain size of the bulk fuel material. The granular fuel additive component coats or covers the granular bulk fuel material.

The invention relates generally to uranium fuel in a nuclear reactor and, more particularly, the inclusion of a fuel additive component to the bulk fuel material. The fuel additive component is selected and provided in an amount such that it is effective to improve one or more properties of the bulk fuel material. The fuel additive component has a grain size that is less than the grain size of the bulk fuel material. The granular fuel additive component coats or covers the granular bulk fuel material.