Abstract: An alloy for biomedical use includes Zr as a main component, Nb the content of which is not less than 0.1% by weight and not greater than 25% by weight, Mo the content of which is not less than 0.1% by weight and not greater than 25% by weight, and Ta the content of which is not less than 0.1% by weight and not greater than 25% by weight. A tensile strength of the alloy is not less than 1000 MPa. A total content of Nb, Mo, and Ta in the alloy is not less than 2% by weight and not greater than 50% by weight. Mass susceptibility of the alloy is not greater than 1.50×10?6 cm3/g. A Young's modulus of the alloy is not greater than 100 GPa. Also disclosed is a medical product including the alloy and a method for producing the alloy.

Abstract: Nuclear fuel alloys or mixtures and methods of making nuclear fuel mixtures are provided. Pseudo-binary actinide-M fuel mixtures form alloys and exhibit: body-centered cubic solid phases at low temperatures; high solidus temperatures; and/or minimal or no reaction or inter-diffusion with steel and other cladding materials. Methods described herein through metallurgical and thermodynamics advancements guide the selection of amounts of fuel mixture components by use of phase diagrams. Weight percentages for components of a metallic additive to an actinide fuel are selected in a solid phase region of an isothermal phase diagram taken at a temperature below an upper temperature limit for the resulting fuel mixture in reactor use. Fuel mixtures include uranium-molybdenum-tungsten, uranium-molybdenum-tantalum, molybdenum-titanium-zirconium, and uranium-molybdenum-titanium systems.

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 fuel rod for a nuclear fission reactor is disclosed and claimed. The fuel rod includes an elongate hollow cladding configured to retain a nuclear fuel therein. The cladding includes an elongate hollow tube. Fiber layers are positioned around the outside surface of the tube or within the tube forming an integral part thereof. Both the tube and the fibers are formed of a ceramic material. A fuel assembly including a plurality of such fuel rods is also disclosed and claimed.

Abstract: Zirconium-based metal alloy compositions comprise zirconium, a first additive in which the permeability of hydrogen decreases with increasing temperatures at least over a temperature range extending from 350° C. to 750° C., and a second additive having a solubility in zirconium over the temperature range extending from 350° C. to 750° C. At least one of a solubility of the first additive in the second additive over the temperature range extending from 350° C. to 750° C. and a solubility of the second additive in the first additive over the temperature range extending from 350° C. to 750° C. is higher than the solubility of the second additive in zirconium over the temperature range extending from 350° C. to 750° C. Nuclear fuel rods include a cladding material comprising such metal alloy compositions, and nuclear reactors include such fuel rods. Methods are used to fabricate such zirconium-based metal alloy compositions.

Abstract: A cladding tube configured for use with nuclear fuels or nuclear feel elements and configured for contact with molten lead or molten lead alloys at up to 800° C. The cladding tube includes a tube including at least one of ferritic/martenisitic steel and austenitic steel. An alloy layer of up to 50 ?m thickness is disposed on a surface of the tube and operable for corrosion resistance. The alloy layer includes 0-25% chromium, 3-15% aluminum and 60-97% iron. A method of making the cladding tube includes the use of a pulsed electron beam to melt the alloy layer on the tube.

Abstract: A method for forming roughness on an outer surface of cladding of a fuel nuclear rod including zirconium includes: positioning the cladding of the nuclear fuel rod at a first electrode and connecting a positive electrode thereto, and positioning a conductive plate at a second electrode and connecting a negative electrode thereto; putting the cladding of the nuclear fuel rod in an electrolyte solution; and applying voltage to the positive electrode and the negative electrode to cause oxidation on the outer surface of the cladding of the nuclear fuel rod. In this case, the electrolyte solution is maintained at 10° C. or lower.

Abstract: A method for production of a fuel cladding tube for a nuclear reactor, characterized by the preparation of an ingot of an alloy of zirconium with the following composition by weight %: 0.8%?Nb?2.8%, traces?Sn?0.65%, 0.015%?Fe?0.40%, C?100 ppm, 600 ppm?O?2300 ppm, 5 ppm?S?100 ppm, Cr+V?0.25%, Hf?75 ppm and F?1 ppm the remainder being zirconium and impurities arising from production. The ingot is then subjected to forging, a hardening and thermomoechanical treatments comprising cold laminations separated by intermediate annealing, all intermediate annealings being carried out at a temperature below the ???+? transition temperature of the alloy, finishing with a recrystallization annealing and resulting in the production of a tube, whereupon an optional external cleaning of the tube is carried out and a mechanical polishing of the external surface of the tube is carried out to give a roughness Ra less than or equal to 0.5 ?m. The invention further relates to a fuel cladding tube obtained thereby.

Abstract: The invention concerns a method of producing a cladding tube for nuclear fuel for a nuclear boiling water reactor. According to the method, a tube is formed which comprises an outer cylindrical component (10) mainly containing zirconium and an inner cylindrical component (20) metallurgically bonded to the outer component (10), wherein also the inner component (20) at least mainly contains zirconium. The inner component (20) has a lower recrystallization temperature than the outer component (10). The cladding tube is final annealed at a temperature and during a time such that the inner component (20) substantially completely recrystallizes and such that the outer component (10) partly recrystallizes but to a lower extent than the inner component (20). The invention also concerns a cladding tube, a fuel assembly for a boiling water reactor as well as the use of a cladding tube.

Abstract: A fuel channel for housing a fuel rod bundle in a boiling water nuclear reactor includes an expanded section to create an increased flow area at a top of the fuel channel and thereby reduce a pressure drop through the fuel channel. The expanded section eliminates a need for channel spacers and a fastener guard.

Abstract: The invention proposes a zirconium-based alloy also containing, by weight, apart from unavoidable impurities, from 0.02 to 1% of iron, from 0.8% to 2.3% of niobium, less than 2000 ppm of tin, less than 2000 ppm of oxygen, less than 80 ppm of carbon, from 5 to 35 ppm of sulphur and less than 0.25% in total of chromium and/or vanadium, the ratio R of the niobium content less 0.5% to the iron content, optionally supplemented by the chromium and/or vanadium content, being lower than 3.

Abstract: A rhenium lined niobium alloy tube for use as a clad tube for nuclear fuel in a nuclear reactor. The tube is produced by an electro deposit process. A graphite mandrel is placed in the electro deposit chamber as the cathode material. Refined rhenium stock is used as the anode material. The chamber is filled with the chloride electrolyte. The chamber is closed and the electrolyte bath is heated. Current and voltage applied across the anode and cathode cause the rhenium to be deposited on the mandrel. Refined niobium alloy is then used as the anode material and applied over the rhenium on the mandrel to a desired thickness. The part is removed from the chamber and ground to the desired outside diameter. The graphite mandrel is removed from the tube.

Abstract: A rhenium lined niobium alloy tube for use as a clad tube for nuclear fuel in a nuclear reactor. The tube is produced by an electro deposit process. A graphite mandrel is placed in the electro deposit chamber as the cathode material. Refined rhenium stock is used as the anode material. The chamber is filled with the chloride electrolyte. The chamber is closed and the electrolyte bath is heated. Current and voltage applied across the anode and cathode cause the rhenium to be deposited on the mandrel. Refined niobium alloy is then used as the anode material and applied over the rhenium on the mandrel to a desired thickness. The part is removed from the chamber and ground to the desired outside diameter. The graphite mandrel is removed from the tube.

Abstract: A method for production of a fuel cladding tube for a nuclear reactor, characterised by the preparation of an ingot of an alloy of zirconium with the following composition by weight %: 0.8%?Nb?2.8%, traces?Sn?0.65%, 0.015%?Fe?0.40%, C?100 ppm, 600 ppm?O?2300 ppm, 5 ppm?S?100 ppm, Cr+V?0.25%, Hf?75 ppm and F?1 ppm the remainder being zirconium and impurities arising from production. The ingot is then subjected to forging, a hardening and thermomoechanical treatments comprising cold laminations separated by intermediate annealing, all intermediate annealings being carried out at a temperature below the ???+? transition temperature of the alloy, finishing with a recrystallisation annealing and resulting in the production of a tube, whereupon an optional external cleaning of the tube is carried out and a mechanical polishing of the external surface of the tube is carried out to give a roughness Ra less than or equal to 0.5 ?m. The invention further relates to a fuel cladding tube obtained thereby.

Abstract: The present invention relates to a component (1) comprising an element (2), which contains zirconium or a zirconium alloy and which has a surface (3) on which a corrosion protective layer (4) is formed, the oxide layer (4) comprising zirconium oxide. The component (1) is intended to be in an oxidising environment (6) and said oxide layer (4) has an outer surface (5) towards said oxidising environment (6). The element (2) comprises a layer (10), that borders said surface (3) and comprises hydrogen and at least one metal from the group of lanthanum elements and/or from the group platinum metals and/or yttrium which in its elemental form or as an oxide have the ability to effectively dissociate oxygen and H2O. The invention also relates to a method for manufacturing the component (1) and a nuclear facility comprising the component (1).

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: A crud-resistant nuclear fuel element cladding in which the axial locations that experience nucleate boiling during reactor full power operation are highly polished so that the maximum size of any surface defect on the highly polished surface is approximately 0.1 microns. The remainder of the cladding surface remains unpolished so that crud is more evenly redistributed over the entire fuel cladding surface to limit the thickness of the crud that is formed to less than 35 microns.

Abstract: The present invention relates to a zirconium alloy having excellent corrosion resistance and mechanical properties and a method for preparing a nuclear fuel cladding tube by zirconium alloy. More particulary, the present invention is directed to a zirconium alloy comprising Zr-aNb-bSn-cFe-dCr-eCu (a=0.05-0.4 wt %, b=0.3-0.7 wt %, c=0.1-0.4 wt %, d=0-0.2 wt % and e=0.01-0.2 wt %, provided that Nb+Sn=0.35-1.0 wt %), and to a method for preparing a zirconium alloy nuclear fuel cladding tube, comprising melting a metal mixture comprising of the zirconium and alloying elements to obtain ingot, forging the ingot at &bgr; phase range, &bgr;-quenching the forged ingot at 1015-1075° C., hot-working the quenched ingot at 600-650° C., cold-working the hot-worked ingot in three to five passes, with intermediate vacuum annealing and final vacuum annealing the worked ingot at 460-540° C.

Abstract: Disclosed herein are zirconium-base alloys excellent in both corrosion resistance and hydrogen absorption property, useful as materials for nuclear reactors. Such a zirconium-base alloy for nuclear reactors comprises 0.5-2 wt. % Sn, 0.07-0.6 wt. % Fe, 0.03-0.2 wt. % Ni, 0.05-0.2 wt. % Cr, and the balance being zirconium and unavoidable impurities, wherein the Fe content (X wt. %) of the zirconium-base alloy and the mean size (Y nm) of precipitates in the zirconium-base alloy are present in a region on the x (Fe content X) and y (mean precipitate size) rectangular coordinates, surrounded by the following five lines: i) Y=−444×X+154, ii) Y=910×X−46, iii) Y=0, iv) Y=300, and v) X=0.6.

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: Cladding tube for a fuel rod for a boiling water reactor fuel element, and its production. The cladding tube is composed practically homogeneously of the constituents of zircaloy and, with the ductility parameter &ggr;=3{square root over ((kd))}/(fr)2≦3.5 (&ggr;=ductility parameter, KD=mean grain diameter; fr=Kearns factor), has an elongation at break of at least 20%, set by low-temperature treatment of an extruded tube blank. The starting body used for the extrusion has a defined distribution of precipitated secondary particles which is produced by &bgr;-quenching and differs in the areas which form the inner surface and outer surface of the extruded tube. At the inner surface, the particles have a greater diameter and are at a greater average distance apart, this distribution being described by the “spacing”.

Abstract: An alloy of zirconium and niobium that includes erbium as a consumable neutron poison, its method of preparation and a component comprising said alloy are provided. This invention relates to an alloy of zirconium and niobium that includes erbium as a consumable neutron poison. The invention also relates to a method for the preparation and conversion of said alloy and a component comprising said alloy. Such an alloy is particularly intended for the manufacture of cladding and/or other elements or structural components of fuel assemblies for nuclear reactors using water as coolant.

Abstract: A corrosion and hydride resistant nuclear fuel rod having a highly corrosion resistant outer portion in which hydride precipitation is inhibited and an inner portion in which hydride precipitation is promoted.

Abstract: A pressurized water reactor fuel assembly with a guide tube and a method for producing a guide tube for control elements are provided. Such guide tubes in pressurized water nuclear reactors which are composed of zirconium alloys (zircaloy-2 and zircaloy-4) show sharp radiation-induced growth in the axial direction at the commencement of their use in the reactor core. The sharp initial growth of the tubes is compensated by an inherent contraction of the tubes. For this purpose, the guide tubes are given internal stresses which are reduced by tube contraction as a result of a radiation-induced supply of energy. During production, guide tubes which are too short are first produced and subsequently lengthened by at least 0.3% to a final dimension in a last production step. In order to lengthen the tube, it may be stretched on a straightening bench.

Abstract: A corrosion and hydride resistant nuclear fuel rod having a highly corrosion resistant outer portion in which hydride precipitation is inhibited and an inner portion in which hydride precipitation is promoted.

Abstract: A corrosion and hydride resistant nuclear fuel rod having a highly corrosion resistant outer portion in which hydride precipitation is inhibited and an inner portion in which hydride precipitation is promoted.

Abstract: Surface preoxidation of the substrate is carried out by bringing the substrate into contact with an oxidizing gas excited by a cold plasma, the substrate being situated in the flowing afterglow of the cold plasma used to excite the oxidizing element and being heated to an oxidation temperature of less than 500.degree. C. A metal oxide is formed at the surface of the preoxidized substrate by heterogeneous oxidation of a metal halide with a gas mixture including an oxidizing element activated by a cold plasma. The oxidizing gas mixture is brought into contact with the halide as directly as possible in the vicinity of the substrate arranged in the far flowing afterglow of the cold plasma. The cold plasma is preferably generated by microwaves. The process can be used in particular for producing a protective coating on a cladding tube of a nuclear fuel rod.

Abstract: A fuel rod for a light water reactor comprises a cladding tube which comprises a zirconium alloy having a composition including 0.6 to 2.0% by weight of Nb, 0.5 to 1.5% by weight of Sn, 0.05 to 0.3% by weight of Fe, and the balance being Zr and incidental impurities; uranium oxide fuel pellets packed in the cladding tube; and end plugs comprising a zirconium alloy and closing both ends of the cladding tube. The cladding tube is sealed by TIG welding with the end plugs. Grain boundaries in each heat affected zone of the cladding tube, which are adjacent to a bead formed by TIG welding, have structural compositions including 4 to 30% by weight of Nb, and 0.9 to 20% by weight of Fe.

Abstract: A corrosion and hydride resistant nuclear fuel rod having a highly corrosion resistant outer portion in which hydride precipitation is inhibited and an inner portion in which hydride precipitation is promoted.

Abstract: In order to provide an austenitic single crystal stainless steel having preferable stress corrosion cracking resistance, strength, and irradiation induced embrittlement resistance so as to extend the life of a nuclear reactor core structure, which is used under a high radiation dose environment, a method is employed, which comprises the steps of homogeneously dispersing carbides into a parent phase of the austenitic single crystal stainless steel by a two step solution heat treatment, and subsequently effecting an ageing heat treatment after rapid cooling for precipitating fine carbides. Austenitic single crystal stainless steel having preferable stress corrosion cracking resistance, strength, and irradiation induced embrittlement resistance can be provided, and the life of nuclear reactor core structure, which is used under a high radiation dose environment, can be extended.

Abstract: A method of producing austenite steel for use in the radiation zone of a nuclear reactor. The method comprising the steps of forming the austenite steel with about 17% by weight chromium, about 9 to 11.5% by weight nickel, about 0.04% by weight carbon, and iron impurities whose content of silicon is about 0.1% by weight and whose total content of sulfur and phosphorous is less than 0.03% by weight; and exposing the austenite steel to a temperature treatment at a temperature less than 1150 .degree. C. to produce a fine grain lattice with grain diameter features under approximately 20 .mu.m.

Abstract: A zirconium alloy tube for forming the whole or the outer portion of a nuclear fuel pencil housing or a nuclear fuel assembly guide tube. The zirconium alloy contains 0.8-1.8 wt. % of niobium, 0.2-0.6 wt. % of tin and 0.02-0.4 wt. % of iron, and has a carbon content of 30-180 ppm, a silicon content of 10-120 ppm and an oxygen content of 600-1800 ppm. The tube may be used when recrystallized or stress relieved.

Abstract: A fuel rod for a light water reactor comprises a cladding tube which comprises a zirconium alloy having a composition including 0.6 to 2.0% by weight of Nb, 0.5 to 1.5% by weight of Sn, 0.05 to 0.3% by weight of Fe, and the balance being Zr and incidental impurities; uranium oxide fuel pellets packed in the cladding tube; and end plugs closing both ends of the cladding tube. The cladding tube is sealed by TIG welding with the end plugs. Precipitates having grain diameters of 0.01 to 0.5 .mu.m and comprise intermetallic compounds containing Zr, Nb and Fe are present at grain boundaries in the structure of heat affected zones of the cladding tube, the heat affected zone being adjacent to a bead formed by TIG welding.

Abstract: A tube of zirconium-based alloy for constituting all or a portion of a cladding or guide tube for a nuclear fuel assembly. The tube is made of an alloy containing, by weight, 1.0-1.7% of tin, 0.55-0.80% of iron, 0.20-0.60% total of chromium and/or vanadium, and 0.10-0.18% of oxygen, with 50-200 ppm of carbon and 50-120 ppm of silicon. The alloy further contains only zirconium and unavoidable impurities, and it is completely recrystallized.

Abstract: A uranium-free fuel for a fast nuclear reactor comprising an alloy of Pu, Zr and Hf, wherein Hf is present in an amount less than about 10% by weight of the alloy. The fuel may be in the form of a Pu alloy surrounded by a Zr--Hf alloy or an alloy of Pu--Zr--Hf or a combination of both.

Abstract: Zirconium-based components for nuclear reactors are disclosed whereby a rare earth or other metal which preferentially concentrates hydrogen when in contact with zirconium is dispersed as a second phase throughout a zirconium-based matrix. The morphology and distribution of the two-phase material is controlled such that the second phase, internal hydrogen absorbing particles, are provided as spherical particles, randomly distributed, to minimize the effects of the occluded hydrogen.

Abstract: The present invention provides a zirconium based alloy member which has very small deformation of elongation and bow occurring due to irradiation growth, a method of manufacturing it, and particularly an channel box for an atomic reactor fuel assembly. A zirconium based alloy plate member having a width of not less than 100 mm and a long length, containing not more than 5 wt % Nb and/or not more 5 wt % Sn, the member having (0001) orientation (Fl value) of hexagonal Zr with respect to longitudinal direction ranging from 0.20 to 0.35, the difference in Fl between the middle and the end being not more than the value calculated from (0.0935.times.Fl-0.00585) and an amount of bow at neutron irradiation of 35 GWd/t which bow occurs in the channel box for a reactor being not more than 2.16 mm.

Abstract: Zirconium alloys for use in an aqueous environment subject to high fluence of a water reactor and characterized by improved corrosion resistance, consisting essentially of 0.3 to 1.8 weight percent tin, 0.1 to 0.65 weight percent iron, the balance of alloys being essentially nuclear grade zirconium with incidental impurities and having a microstructure of Zr.sub.3 Fe second phase precipitates distributed uniformly intragranularly and intergranularly to form radiation resistant second phase precipitates in the alloy matrix.

Abstract: Zirconium alloys for use in an aqueous environment subject to high fluence of a water reactor and characterized by improved corrosion resistance, consisting essentially of from 0.5 to 3.25 weight percent niobium, from 0.3 to 1.8 weight percent tin, the balance of alloys being essentially nuclear grade zirconium with incidental impurities and having a microstructure of beta niobium second phase precipitates distributed uniformly intragranularly and intergranularly to form radiation resistant second phase precipitates in the alloy matrix.

Abstract: A process for fabricating nuclear fuel rod cladding tube comprising beta quenching a zirconium alloy billet consisting essentially of from 0.5 to 3.25 weight percent niobium, from 0.3 to 1.8 weight percent tin, the balance of the alloy being essentially nuclear grade zirconium with incidental impurities by heating to a temperature in the beta range above 950.degree. C. and rapidly quenching the billet to a temperature below the .alpha. plus .beta. to .alpha. transformation temperature to form a martensitic structure; extruding the beta-quenched billet at a temperature below 600.degree. C. to form a hollow; annealing the hollow by heating at a temperature up to 590.degree. C.; pilgering the annealed hollow; and final annealing the pilgered annealed hollow to a temperature up to 590.degree. C.

Abstract: A process for fabricating nuclear fuel rod cladding tube comprising beta quenching a zirconium alloy billet consisting essentially of 0.3 to 1.8 weight percent tin, 0.1 to 0.65 weight percent iron, the balance of the alloy being essentially nuclear grade zirconium with incidental impurities by heating to a temperature in the beta range greater than about 1000.degree. C. and rapidly quenching the billet to a temperature below the .alpha. plus .beta. to a transformation temperature to form a martensitic structure; extruding the beta-quenched billet at a temperature between 600.degree. and 750.degree. C. to form a hollow; annealing the hollow by heating at a temperature up to about 700.degree. C.; pilgering the annealed hollow; and final annealing the pilgered annealed hollow to a temperature up to about 700.degree. C. to form the nuclear fuel rod cladding tube comprising the alloy having a microstructure of Zr.sub.

Abstract: The alloy has a base composition similar to that of a zirconium alloy of known type used for the manufacture of an element intended for use in the core of a nuclear reactor, such as a cladding tube, a guide tube, or another structural element of a fuel assembly. In addition, the alloy contains sulphur in a proportion by weight of between 8 and 100 ppm and preferably between 8 and 30 ppm.

Abstract: Fuel rod 2 has a fuel cladding tube 3, and upper end plug 5 and a lower end plug 6 welded to the ends of fuel cladding tube 3. He gas 1 and U pellets 4 are filled in the fuel cladding tube 3. The He gas pressure 1 is about 8 atm, and the average crystal grain size of the U pellet 4 is in the range of 30-60 .mu.m. The fuel rod can be manufactured at a lower manufacturing cost, while maintaining the fuel integrity the same as in a conventional fuel rod.

Abstract: A composite zirconium alloy component that exhibits a reduced propensity for irradiation growth and enhanced corrosion resistance when in a radiation field. The component is formed to have an inner core and two oppositely-disposed outer layers that are metallurgically bonded to the inner core. The inner core and the outer layers are formed from two different zirconium alloys, with the inner core alloy contributing to the ability of the component to resist dimensional distortions as a result of irradiation growth, while the outer layer alloy contributes to the ability of the component to resist corrosion. As such, the alloys are combined within the component in a manner that exploits the different corrosion and irradiation-resistance properties of the alloys.

Abstract: A nuclear reactor core fuel element is composed of nanophase high temperature materials. An array of the fuel elements in rod form are joined in an open geometry fuel cell that preferably also uses such nanophase materials for the cell structures. The particular high temperature nanophase fuel element material must have the appropriate mechanical characteristics to avoid strain related failure even at high temperatures, in the order of about 3000.degree. F. Preferably, the reactor type is a pressurized or boiling water reactor and the nanophase material is a high temperature ceramic or ceramic composite. Nanophase metals, or nanophase metals with nanophase ceramics in a composite mixture, also have desirable characteristics, although their temperature capability is not as great as with all-ceramic nanophase material. Combinations of conventional or nanophase metals and conventional or nanophase ceramics can be employed as long as there is at least one nanophase material in the composite.

Abstract: A tube for constituting all or part of a cladding or guide tube for a fuel assembly is made from an alloy containing, by weight, 0.4% to 0.6% of tin, 0.5% to 0.8% of iron, 0.35% to 0.50% of vanadium, and 0.10% to 0.18% of oxygen, 100 ppm to 180 ppm of carbon and 50 ppm to 120 ppm of silicon. The alloy contains nothing else apart from zirconium and unavoidable impurities and it is completely recrystallized.

Abstract: A fuel assembly for a pressurized water reactor having a fuel rod with a high strength cladding tube including an inner tubular layer of a zirconium alloy with alloying components of molybdenum and 3 to 6 weight percent bismuth, the balance zirconium.

Abstract: In a nuclear fuel rod having a zirconium liner and a method of manufacturing the same, the outer surface of a zircaloy cladding tube in which fuel pellets are filled has an oxide film having fine irregularities of which the pitch is 1 .mu.m or less. The fine irregularities are formed by oxidizing the surface in high temperature steam or polishing the surface of the cladding tube. The surface of the fuel rod can effectively trap radioactive substances in the reactor water.

Abstract: A zirconium alloy tube for forming the whole or the outer portion of a nuclear fuel pencil housing or a nuclear fuel assembly guide tube. The zirconium alloy contains 0.8-1.8 wt. % of niobium, 0.2-0.6 wt. % of tin and 0.02-0.4 wt. % of iron, and has a carbon content of 30-180 ppm, a silicon content of 10-120 ppm and an oxygen content of 600-1800 ppm. The tube may be used when recrystallized or stress relieved.