Abstract: An additive manufacturing method including repeatedly applying a layer of building material on a previously selectively solidified building material layer and scanning the layer at positions corresponding to the cross-section of the object in this layer, where the laser radiation is generated by a laser light source and is directed onto the building material layer via optical components. An optics compartment is encased by an optics compartment housing and accommodates the optical components. A defined gas atmosphere is maintained inside of the optics compartment, wherein the relative humidity of the defined gas atmosphere is kept below 3%.

Abstract: A composite nuclear reactor component comprises a support and a protective layer (2). The support contains a substrate (1) based on a metal. The substrate is coated with an interposed layer (3) positioned between the substrate (1) and the protective layer (2). The protective layer (2) is composed of a material which comprises amorphous chromium carbide. The nuclear reactor component provides for improved resistance to oxidation, hydriding, and/or migration of undesired material.

Abstract: The present invention relates to a nuclear fuel pellet laminate structure having enhanced thermal conductivity, including a nuclear fuel pellet; and a thermally conductive metal layer disposed above or below the nuclear fuel pellet, and a method for manufacturing the same.

Abstract: The invention relates to a nuclear fuel cladding comprising: i) a substrate containing a zirconium-based inner layer, optionally coated with at least one intermediate layer formed by at least one intermediate material selected from among tantalum, molybdenum, tungsten, niobium, vanadium, hafnium or the alloys thereof; and ii) at least one protective outer layer placed on the substrate and formed by a protective material selected from either chromium or an alloy of chromium. The nuclear fuel cladding produced using the method of the invention has improved resistance to oxidation/hydriding. The invention also relates to the method for the production of the nuclear fuel cladding by ion etching of the surface of the substrate and deposition of the outer layer on the substrate with a high power impulse magnetron sputtering method (HiPIMS), as well as to the use thereof to protect against oxidation and/or hydriding.

Abstract: A methodology is disclosed for compaction of a ceramic matrix of certain nuclear fuels incorporating neutron poisons, whereby those poisons aid in reactor control while aiding in fuel fabrication. Neutronic poisons are rare-earth oxides that readily form eutectics suppressing fuel fabrication temperature, of particular importance to the fully ceramic microencapsulated fuel form and fuel forms with volatile species.

Abstract: Process for manufacturing a nuclear component comprising i) a support containing a substrate based on a metal (1), the substrate (1) being coated or not coated with an interposed layer (3) positioned between the substrate (1) and at least one protective layer (2) and ii) the protective layer (2) composed of a protective material comprising amorphous chromium carbide; the process comprising a step a) of vaporizing a mother solution followed by a step b) of depositing the protective layer (2) onto the support via a process of chemical vapor deposition of an organometallic compound by direct liquid injection (DLI-MOCVD).

Abstract: This disclosure describes various configurations and components for bimetallic and trimetallic claddings for use as a wall element separating nuclear material from an external environment. The cladding materials are suitable for use as cladding for nuclear fuel elements, particularly for fuel elements that will be exposed to sodium or other coolants or environments with a propensity to react with the nuclear fuel.

Abstract: A zirconium alloy nuclear reactor cylindrical cladding has an inner Zr substrate surface (10), an outer volume of protective material (22) consisting of Zr—Al, and an integrated middle volume (20) of zirconium oxide, zirconium and protective material, where the protective material is applied by impaction at a velocity greater than 340 meters/second to provide the integrated middle volume (20) resulting in structural integrity for the cladding.

Abstract: The invention relates to a nuclear fuel cladding totally or partially made of a composite material with a ceramic matrix containing silicon carbide (SiC) fibers as a matrix reinforcement and an interphase layer provided between the matrix and the fibers, the matrix including silicon carbide as well as at least one of the following additional carbides: titanium carbide (TiC), zirconium carbide (Zrc), and ternary titanium silicon carbide (Ti3SiC2). When irradiated and at temperatures of between 800° C. and 1200° C., said cladding can mechanically maintain the nuclear fuel within the cladding while enabling optimal thermal-energy transfer towards the coolant. The invention also relates to a method for making the nuclear fuel cladding.

Abstract: A sheathed, annular metal fuel system is described. A metal fuel pin system is described that includes an annular metal nuclear fuel alloy. A sheath may surround the metal nuclear fuel alloy, and a cladding may surround the sheath. A gas plenum may also be present. Mold arrangements and methods of fabrication of the sheathed, annular metal fuel are also described.

Abstract: A zirconium alloy nuclear reactor cylindrical cladding has an inner Zr substrate surface (10), an outer volume of protective material (22), and an integrated middle volume (20) of zirconium oxide, zirconium and protective material, where the protective material is applied by impaction at a velocity greater than 340 meters/second to provide the integrated middle volume (20) resulting in structural integrity for the cladding.

Abstract: In general, the present invention is directed to novel nuclear fuel rod claddings that have better performance characteristics compared to current claddings, particularly during a severe accident, such as a loss of coolant accident. The present invention provides a duplex cladding having two layers, an inner Mo or Mo-alloy layer and a protective layer disposed on the outside of the Mo or Mo-alloy layer. Optionally, the Mo or Mo-alloy layer may have a coating disposed on its inner surface to provide additional capability with the fuel pellets, thereby creating a triplex cladding.

Abstract: The invention provides a nuclear reactor cladding, wherein at least one layer of coating is deposited on the exterior surface of the cladding. A nuclear reactor cladding, wherein at least one layer of coating is deposited on the interior surface of the cladding. A method of coating a nuclear reactor cladding, with the steps of selecting the cladding and depositing at least one layer of a first coating on the cladding.

Abstract: A zirconium alloy nuclear reactor cylindrical cladding has an inner Zr substrate surface (10), an outer volume of protective material (22), and an integrated middle volume (20) of zirconium oxide, zirconium and protective material, where the protective material is applied by impaction at a velocity greater than 340 meters/second to provide the integrated middle volume (20) resulting in structural integrity for the cladding.

Abstract: A dual-cooled nuclear fuel rod and a method of manufacturing the same are provided. The nuclear fuel rod includes an outer cladding tube having a circular cross section, an inner cladding tube having an outer diameter smaller than an inner diameter of the outer cladding tube, and a length longer than the outer cladding tube, and located in parallel in the outer cladding tube, a pellet charged in a space between the outer and inner cladding tubes and generating energy by nuclear fission, and first and second end plugs coupling opposite ends of the outer cladding tube to stepped outer joints formed on outer circumferences of first ends thereof and coupling opposite ends of the inner cladding tube to stepped inner joints formed on inner circumferences of the first ends thereof.

Abstract: There is provided a fuel rod assembly comprising a first component of a zirconium-based material. The first component is in contact with or is located adjacent to a second component of a material different from the zirconium-based material, e.g. a nickel-based or iron-based alloy. A coating is disposed on an outer surface of the first component, which is effective to reduce an electrochemical corrosion potential difference between the first component and the second component relative to an electrochemical corrosion potential difference between the first component and the second component without the coating.

Abstract: A method and apparatus for a fret resistant fuel rod for a Boiling Water Reactor (BWR) nuclear fuel bundle. An applied material entrained with fret resistant particles is melted or otherwise fused to a melted, thin layer of the fuel rod cladding. The applied material is made of a material that is chemically compatible with the fuel rod cladding, allowing the fret resistant particles to be captured in the thin layer of re-solidified cladding material to produce an effective and resilient fret resistant layer on an outer layer of the cladding.

Abstract: A zirconium alloy nuclear reactor cylindrical cladding has an inner Zr substrate surface (10), an outer volume of protective material (22), and an integrated middle volume (20) of zirconium oxide, zirconium and protective material, where the protective material is applied by impaction at a velocity greater than 340 meters/second to provide the integrated middle volume (20) resulting in structural integrity for the cladding.

Abstract: A liquid-metal cooled fast reactor core having a nuclear fuel assembly constituted of nuclear fuel rods with varying cladding thicknesses in reactor core regions, in which: the nuclear fuel assembly (1) of a liquid-metal cooled fast reactor includes nuclear fuel assemblies (1a, 1b and 1c) in inner, middle and outer reactor core regions, respectively, and is installed in a hexagonal duct (3) with nuclear fuel materials (2-2a, 2-2b and 2-2c) surrounded by respective claddings (2-1a, 2-1b and 2-1c), and the claddings (2-1a, 2-1b and 2-1c) of a nuclear fuel rod (2a) in the inner reactor core region, a nuclear fuel rod (2b) in the middle reactor core region and a nuclear fuel rod (2c) in the outer reactor core region are formed at different thicknesses. The reactor core can flatten power distribution using a single-enrichment nuclear fuel in the liquid-metal cooled fast reactor.

Abstract: A zirconium alloy with a coating layer formed on a surface comprising a mixed layer, the mixed layer comprises one or more very high temperature oxidation resistant material and zirconium alloy parent material selected from the group consisting of Y2O3, SiO2, ZrO2, Cr2O3, Al2O3, Cr3C2, SiC, ZrC, ZrN, Si and Cr, and in a vertical direction on a boundary between the mixed layer and the zirconium alloy parent material is formed a gradient of compositions between the very high temperature oxidation resistance material and the zirconium alloy parent material.

Abstract: A core of a light water reactor having a plurality of fuel assemblies, which are loaded in said core, having nuclear fuel material containing a plurality of isotopes of transuranium nuclides, an upper blanket zone, a lower blanket zone, and a fissile zone, in which the transuranium nuclides are contained, disposed between the upper blanket zone and the lower blanket zone, wherein a ratio of Pu-239 in all the transuranium nuclides contained in the loaded fuel assembly is in a range of 40 to 60% when burnup of the fuel assembly is 0, sum of a height of the lower blanket zone and a height of the upper blanket zone is in a range of 250 to 600 mm, and the height of said lower blanket zone is in a range of 1.6 to 12 times the height of the upper blanket zone.

Abstract: A nuclear fuel rod for a fast reactor includes tubular fuel materials comprising a hollow portion formed therein, a tubular inner pipe inserted into the hollow portion of the tubular fuel materials to prevent collapse of the tubular fuel materials due to combustion of nuclear fuel, a tubular cladding pipe which surrounds the tubular fuel materials, and a liquid metal, or He gas or vacuum applied in a gap between the tubular fuel materials and the tubular cladding pipe.

Abstract: A water reactor fuel cladding tube (4) is described. The tube (4) comprises an outer layer (6) of a first zirconium based alloy and has metallurgically bonded thereto an inner layer (7) of a second zirconium based alloy. The inner layer protects (7) the cladding tube (4) against stress corrosion cracking. The second zirconium based alloy comprises tin as an alloying material, and each one of the zirconium based alloys comprises at least 96 percent by weight zirconium. The first zirconium based alloy comprises at least 0.1 percent by weight niobium. A method of manufacturing the cladding tube (4) is also described and comprises the step of co-extruding two tubes of different zirconium based alloys to produce the cladding tube (4).

Abstract: Method of treating sodium contained in the interconnected open pores of a structure placed in a cladding, the pores furthermore containing a radioactive substance. The method comprises the following successive steps: a) at least two slits are made over the entire length of the cladding; b) the sodium is converted to sodium carbonate by a carbonation reaction by bringing the structure into contact, via the slits, with a reactive gas mixture comprising steam, carbon dioxide and a gas inert with respect to sodium, in such a way that the expansion of the carbonate causes the cladding and the structure to open starting from the slits and results in the carbonation reaction propagating into the structure.

Abstract: A multi-layered cladding material including a ceramic matrix composite and a metallic material, and a tube formed from the cladding material. The metallic material forms an inner liner of the tube and enables hermetic sealing of thereof. The metallic material at ends of the tube may be exposed and have an increased thickness enabling end cap welding. The metallic material may, optionally, be formed to infiltrate voids in the ceramic matrix composite, the ceramic matrix composite encapsulated by the metallic material. The ceramic matrix composite includes a fiber reinforcement and provides increased mechanical strength, stiffness, thermal shock resistance and high temperature load capacity to the metallic material of the inner liner. The tube may be used as a containment vessel for nuclear fuel used in a nuclear power plant or other reactor. Methods for forming the tube comprising the ceramic matrix composite and the metallic material are also disclosed.

Abstract: Disclosed herein are a nuclear fuel rod for fast reactors, which includes an oxide coating layer formed on the inner surface of a cladding, and a manufacturing method thereof. The nuclear fuel rod for fast reactors, which includes the oxide coating layer formed on the inner surface of the cladding, can increase the maximum permissible burnup and maximum permissible temperature of the metallic fuel slug for fast reactors so as to prolong the its lifecycle in the fast reactors, thus increasing economic efficiency. Also, the fuel rod is manufactured in a simpler manner compared to the existing method, in which a metal liner is formed, and the disclosed method enables the cladding of the fuel rod to be manufactured in an easy and cost-effective way.

Abstract: A new nuclear fuel element has been developed to be used in particular in fourth generation gaseous heat exchanger reactors working with a fast neutron flow. With a composite plate structure, the element (1) according to the invention comprises a network of cells (8), more preferably of honeycomb shape, in each of which is placed a nuclear fuel pellet (10). Radial and axial gaps are provided in each cell (8) to compensate for the differential expansion between fissile materials and structural materials inherent in the operation of the plate (1).

Abstract: A fuel pebble for use in a fusion-fission engine includes a buffer material and a fertile or fissile fuel shell surrounding the buffer material. The fuel pebble also includes a containment shell surrounding the fertile or fissile fuel shell. The containment shell includes silicon carbide. The fuel pebble further includes a composite material layer surrounding the containment shell and a cladding layer surrounding the composite material layer.

Abstract: A sheathed, annular metal fuel system is described. A metal fuel pin system is described that includes an annular metal nuclear fuel alloy. A sheath may surround the metal nuclear fuel alloy, and a cladding may surround the sheath. A gas plenum may also be present. Mold arrangements and methods of fabrication of the sheathed, annular metal fuel are also described.

Abstract: The invention relates to a nuclear fuel cladding totally or partially made of a composite material with a ceramic matrix containing silicon carbide (SiC) fibers as a matrix reinforcement and an interphase layer provided between said matrix and said fibers, the matrix including at least one carbide selected from titanium carbide (TiC), zirconium carbide (ZrC), or ternary titanium silicon carbide (Ti3SiC2). When irradiated and at temperatures of between 800° C. and 1200° C., said cladding can mechanically maintain the nuclear fuel within the cladding while enabling optimal thermal-energy transfer towards the coolant. The invention also relates to a method for making the nuclear fuel cladding.

Abstract: A water reactor fuel cladding tube (4) is described. The tube (4) comprises an outer layer (6) of a first zirconium based alloy and has metallurgically bonded thereto an inner layer (7) of a second zirconium based alloy. The inner layer protects (7) the cladding tube (4) against stress corrosion cracking. The second zirconium based alloy comprises tin as an alloying material, and each one of the zirconium based alloys comprises at least 96 percent by weight zirconium. The first zirconium based alloy comprises at least 0.1 percent by weight niobium. A method of manufacturing the cladding tube (4) is also described and comprises the step of co-extruding two tubes of different zirconium based alloys to produce the cladding tube (4).

Abstract: A dual-cooled nuclear fuel rod and a method of manufacturing the same are provided. The nuclear fuel rod includes an outer cladding tube having a circular cross section, an inner cladding tube having an outer diameter smaller than an inner diameter of the outer cladding tube, and a length longer than the outer cladding tube, and located in parallel in the outer cladding tube, a pellet charged in a space between the outer and inner cladding tubes and generating energy by nuclear fission, and first and second end plugs coupling opposite ends of the outer cladding tube to stepped outer joints formed on outer circumferences of first ends thereof and coupling opposite ends of the inner cladding tube to stepped inner joints formed on inner circumferences of the first ends thereof.

Abstract: A nuclear fuel element having a thick walled lower section that transitions to a thinner walled upper section with the transition forming an annular interior ledge that supports the fuel pellets spaced above a bottom end plug. The space between the fuel pellets and the bottom end plug forms a gas collection plenum that assures the necessary void volume exists to maintain margin to rod internal pressure limits.

Abstract: There is provided a fuel rod assembly comprising a first component of a zirconium-based material. The first component is in contact with or is located adjacent to a second component of a material different from the zirconium-based material, e.g. a nickel-based or iron-based alloy. A coating is disposed on an outer surface of the first component, which is effective to reduce an electrochemical corrosion potential difference between the first component and the second component relative to an electrochemical corrosion potential difference between the first component and the second component without the coating.

Abstract: A tubular body includes a tubular fiber-reinforced carbonaceous substrate and an SiC layer. The tubular fiber-reinforced carbonaceous substrate includes an aggregate formed of ceramic fibers, and a carbonaceous material filled in interstices between the ceramic fibers. The SiC layer is formed at least on an outer surface of the tubular fiber-reinforced carbonaceous substrate in which silicon atoms are diffused from a boundary region between the fiber-reinforced carbonaceous substrate and the SiC layer to an inside of the fiber-reinforced carbonaceous substrate.

Abstract: The present invention relates to a fuel rod of a nuclear fuel assembly having a vase-like compression spring adapted to increase the internal volume thereof wherein when the vase-like compression spring is inserted into a cladding tube, it has a relatively smaller volume occupied inside the fuel rod when compared with the existing coil type compression spring, such that the vase-like compression spring can ensure a sufficient space portion receiving the fission gases generated during the operation of the fuel rod, thereby increasing the burn-up performance of the fuel rod and the mechanical integrity thereof.

Abstract: Method for producing fuel rods characterized in that it comprises the steps of: a) placing a sleeve on an open end (30a) of a cladding (30), said sleeve comprising a passage provided with a shoulder designed to protect a surface of the open end (30a) of the cladding (30), b) inserting the end of the cladding (30a) provided with the sleeve into the cladding nose, c) isolating a space for receiving the pellets and an outer space, d) filling the cladding with pellets, e) interrupting said filling when the cladding contains a determined number of pellets, f) removing the end (30a) of the cladding from the cladding nose, g) ablating the sleeve. Device for carrying out the method according to the invention and a protective sleeve for nuclear fuel cladding.

Abstract: A fuel rod includes a cladding tube with a wear-inhibiting coating. In one embodiment, the coating is made of a metallic powder material that is applied to the exterior surface of the cladding tube using a thermal spray process. In an alternative embodiment, the coating is a composite made of a metallic powder material, and a ceramic powder material or a metal oxide hard phase powder material that is simultaneously applied with the metallic powder material to coat the cladding tube. The coating can be applied to selected areas of the fuel rods where debris tends to fret the fuel rod.

Abstract: The invention relates to a heating rod for a pressurizer of a primary cooling system of a pressurized-water nuclear reactor, the rod comprising a metal outer shell (36) of longitudinally elongate shape having an external surface (62), and a heating element (40) mounted inside the shell (36). It comprises an anti-corrosion coating (60) covering at least part of the external surface (62) of the shell (36).

Abstract: A fuel element for nuclear power generation made up of at least one coated UO2 fuel kernel embedded in a matrix containing Zr. The kernel and the element each having a coating that provides desired spacing and fission product barrier protection. The fuel enables the functioning and deployment of small scale nuclear reactors with a various features desired for deployment of such devices in developing nations, with limited electrical distribution infrastructure.

Abstract: A high Fe-containing zirconium composition having excellent corrosion resistance and a preparation method thereof. Specifically, disclosed are a high Fe-containing zirconium composition having excellent corrosion resistance and a preparation method thereof, the composition comprising: 0.5-1.0 wt % iron; 0.25-0.5 wt % chromium; 0.06-0.18 wt % oxygen; at least one element selected from the group consisting of 0.2-0.5 wt % tin, 0.1-0.3 wt % niobium and 0.05-0.3 wt % copper; and the balance of zirconium. The zirconium alloy has excellent corrosion resistance, and thus can be used as a material for nuclear fuel claddings, spacer grids and nuclear reactor core structures in light water reactor and heavy water reactor nuclear power plants.

Abstract: A set of alloy formulations is disclosed to use with thorium based nuclear fuels in a fast spectrum reactor; with thorium based nuclear fuels in existing thermal spectrum power reactors; for medical isotope production in the epithermal, the fast, the fission spectrum and the thermal spectra; and to use as fuel in test and experimental reactors that are non proliferative. The alloys form inert metal matrixes to hold fine particles of dispersed thorium containing fuel. The formulations also are useful for the production of medical and commercial isotopes in the high energy, fast and epithermal neutron spectra.

Abstract: A zirconium-based alloy, suitable for use in a corrosive environment, where it is subjected to increased radiation and comprises 0.5-1.6 percentage by weight Nb and 0.3-0.6 percentage by weight Fe. The alloy is characterised in that it comprises 0.5-0.85 percentage by weight Sn.

Abstract: The present invention provides a nuclear fuel assembly, where a boron-containing compound is used as a burnable poison and is distributed in a majority of the rods in the assembly. The assembly comprises a plurality of fuel rods, each fuel rod containing a plurality of nuclear fuel pellets, wherein at least one fuel pellet in more than 50% of the fuel rods in the fuel assembly comprises a sintered admixture of a metal oxide, metal carbide or metal nitride and a boron-containing compound.

Abstract: A fuel element for a pressurized water reactor is described. The fuel element contains a laterally open skeleton having control-rod guide tubes each with a first end and a second end, spacers fastened to the control-rod guide tubes, a fuel element head disposed at the first end of the control-rod guide tubes, and a fuel element foot disposed at the second end of the control-rod guide tubes. Gastight cladding tubes are inserted into the skeleton and each is filled with a column of fuel pellets. At least some of the gastight cladding tubes have a multilayer wall. The multilayer wall is formed of a mechanically stable matrix containing a first zirconium alloy disposed in a middle of the multiplayer wall; and a thinner protective layer of a second zirconium alloy alloyed to a lesser extent than the first zirconium alloy. The thinner protective layer is bound metallurgically to the matrix and is disposed on an inside of the matrix facing the fuel pellets.

Abstract: A fuel element for a pressurized water reactor is described. The fuel element contains a laterally open skeleton having control-rod guide tubes each with a first end and a second end, spacers fastened to the control-rod guide tubes, a fuel element head disposed at the first end of the control-rod guide tubes, and a fuel element foot disposed at the second end of the control-rod guide tubes. Gastight cladding tubes are inserted into the skeleton and each is filled with a column of fuel pellets. At least some of the gastight cladding tubes have a multilayer wall. The multilayer wall is formed of a mechanically stable matrix containing a first zirconium alloy disposed in a middle of the multiplayer wall; and a thinner protective layer of a second zirconium alloy alloyed to a lesser extent than the first zirconium alloy. The thinner protective layer is bound metallurgically to the matrix and is disposed on an inside of the matrix facing the fuel pellets.

Abstract: The method of protectively coating metallic uranium which comprises dipping the metallic uranium in a molten alloy comprising about 20-75% of copper and about 80-25% of tin, dipping the coated uranium promptly into molten tin, withdrawing it from the molten tin and removing excess molten metal, thereupon dipping it into a molten metal bath comprising aluminum until it is coated with this metal, then promptly withdrawing it from the bath.

Abstract: A metallic uranium article having a protective coating of a copper-tin alloy containing from 45 to 50% by weight of copper and from 55 to 50% by weight of tin, said alloy being firmly bonded to the metallic uranium.

Abstract: An improved fuel element for use in a nuclear reactor comprised of a central core of nuclear material, which is surrounded by a composite cladding. The cladding has an outer metallic tubular portion comprised of well-known cladding alloys used for such purposes. Metallurgically bonded to the outer metallic tubular portion is a commercially pure zirconium microalloyed with a controlled quantity of iron. The zirconium microalloyed with iron produced an inner metallic barrier having a beneficial balance between stress corrosion crack resistance and corrosion resistance while retaining other beneficial properties of pure zirconium, such as ductility.

Abstract: A component (1) designed for use in a light water reactor and at least partly comprised by a metal and/or a metal alloy presents a coatings (4, 7) at its outer surface (3) and its inner surface(5). The coating (4 and 7 respectively) has as its task to protect the surface (3 and 5 respectively), against oxidation, corrosion, wear and hydration. The coating (4 and 7 respectively) suitably comprises at least one of zirconium dioxide (ZrO2) and zirconium nitride (ZrN).