Abstract: This invention relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material.Additionally, this invention relates to a process for producing a rare earth-containing powder compact comprising crushing a rare earth-containing alloy in water, compacting the crushed alloy material, drying the compacted alloy material at a temperature below the phase transformation temperature of the material, and treating the compacted alloy material with a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material.Rare earth-containing alloys suitable for use in producing magnets utilizing the powder metallurgy technique, such as Nd-Fe-B and Sm-Co alloys, can be used.

Abstract: This invention relates to a powder substantially of dental metal, which powder is suitable for the manufacture of a dental restoration such as a crown or a bridge, comprising a substructure of dental metal and a fired on coating of a dental ceramic material. The powder comprises a core substantially of a dental metal, which core is coated with one or more layers substantially of metal which protect the dental metal of the core during sintering against oxidation and/or reduce the temperature at which the powder is sintered.The invention also relates to a process for the manufacture of a dental restoration such as a crown or a bridge, comprising a substructure of a dental metal and a fired on coating of a dental ceramic material.

Abstract: The invention provides a composite soft magnetic material which is prepared by coating soft magnetic metal particles with a high resistance soft magnetic substance, preferably by mechano-fusion, applying electricity to the coated particles in a mold cavity between punches serving as electrodes, for example, to thereby create a plasma, and thereafter further conducting electricity to effect plasma activated sintering. There is obtained a composite material which possesses both the high saturation magnetic flux density and high magnetic permeability characteristic of the soft magnetic metal and the high electric resistivity characteristic of the high resistance soft magnetic substance.

Abstract: A cast product made from metallic material and ceramic material with the ceramic material being an insert, comprises an aggregated body of capsule particles, the capsule particle including a ceramic particle coated with metallic particles, and metallic material cast over the aggregated body.

Abstract: A porous metal block for selectively removing solder or braze from a substrate is disclosed. The block comprises a plurality of protrusions which absorb solder or braze through capillary action. The number and dimensions of the protrusions vary depending on the application. Also disclosed is a process for making such a block involving a unique two steps sintering process.

Abstract: Disclosed is a method of producing dense refractory products, comprising:(a) obtaining a quantity of exoergic material in powder form capable of sustaining a combustion synthesis reaction;(b) removing absorbed water vapor therefrom;(c) cold-pressing said material into a formed body;(d) plasma spraying said formed body with a molten exoergic material to form a coat thereon; and(e) igniting said exoergic coated formed body under an inert gas atmosphere and pressure to produce self-sustained combustion synthesis.Also disclosed are products produced by the method.

Abstract: An improved method of forming a composite body of a metal, intermetallic or ceramic matrix reinforced with niobium filaments, particles, platelets or mixtures thereof, the method comprising admixing the niobium reinforcing material with powders of the matrix component elements, forming the admixture into a desired shape and converting the powders to a matrix reinforced with the niobium material, the improvement wherein the reinforcing material has a surface coating thereon of a compound Nb.sub.2 O.sub.5, wherein the compound NbO reacts during formation of the matrix with a portion of at least one of the powdered elements to form a barrier layer at the reinforcer-matrix interface to prevent further reaction between the reinforcer and the matrix component elements. Also disclosed is a method of treating niobium particles, filaments, platelets or mixtures thereof by exposing the surface thereof to molecular O.sub.2 at temperatures and pressure conditions such that the niobium and molecular O.sub.

Abstract: Isotropic permanent magnet formed of a sintered body having a mean crystal grain size of 1-160 microns and a major phase of tetragonal system comprising, in atomic percent, 10-25% of R wherein R represents at least one of rare-earth elements including Y, 3-23% of B and the balance being Fe. As additional elements M, Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni or W may be incorporated.The magnets can be produced through a powder metallurgical process resulting in high magnetic properties, e.g., up to 7 MGOe or higher energy product.

Abstract: A composite material is provided which includes a discrete phase including grains made of a first substance; and a continuous phase including a thin coating film made of a second substance and formed on the surface of each of the grains. The thin coating film has a mean thickness smaller than the mean particle size of the grains. The grains are separated substantially from each other by the thin coating film. The porosity of the composite material is 5% or less.

Abstract: The invention relates to a composite hard metal body of hard material, a binder and embedded reinforcing material, as well as to a process for the production of the composite hard metal body by methods of powder metallurgy.In order to create a composite hard metal body with improved toughness under load, improved hardness and a lower fracture susceptibility, the invention proposes to build in monocrystalline, preferably needle-shaped and/or platelet-shaped reinforcing materials, coated with an inert layer with respect to the binder metal phase and consisting of borides and/or carbides, and/or nitrides and/or carbonitrides of the elements of Groups IVa or Va or mixtures thereof and/or coated monocrystalline reinforcing material of SiC, Si.sub.3 N.sub.4, Si.sub.2 N.sub.2 O, Al.sub.2 O.sub.3, ZrO.sub.2, AlN and/or BN.

Abstract: A magnetically anisotropic R-T-B magnet having crystal grains having aspect ratios of 2 or more and showing a substantially uniform maximum energy product distribution is produced by (a) rapidly quenching an alloy melt; (b) finely pulverizing the rapidly quenched alloy to provide magnetic powder; (c) mixing the magnetic powder with a carbon-containing additive; (d) coating the resulting mixture with a protective layer of a first lubricant such as BN substantially unreactive with the alloy components; (e) compressing it; (f) further coating the resulting compressed body with a second lubricant such as graphite or graphite+glass; and (g) further compressing it.

Abstract: Disclosed are a sliding material comprising a backing metal having a porous metal layer formed on the surface thereof in which pores are defined and a composition for impregnation coating impregnated and coated to the pores and the surface thereof, wherein the composition for impregnation coating is a composition composed of (a) 5-30 vol % of metal lead having a relative surface area of 1,000-8,500 cm.sup.2 /g in an average particle size, and the remaining portion substantially composed of PTFE, a sliding material comprising a backing metal having porous metal layer formed on the surface thereof in which pores are defined and a composition for impregnation coating impregnated and coated to the pores and the surface thereof, wherein the composition for impregnation coating is a composition composed of (b) 5-30 vol % of metal lead having a relative surface area of 1,000-8,500 cm.sup.2 /g in an average particle size, 0.

Abstract: The present invention relates to a process for forming a composite strip material without any sintering step. The process includes blending a powdered high conductivity material such as powdered copper with a powdered low thermal expansion phase material such as a nickel-iron alloy, compacting the powders to form a green composite strip, heating the green strip to a hot rolling temperature and hot rolling the heated strip to a desired gauge. The heated strip is reduced less than about 45% to minimize the deformation of the low thermal expansion phase particles.

Abstract: A method for depositing a composite coating on a substrate is provided. The coating contains a mixture of ductile metal particles and a uniformly dispersed polymer particles. The polymer is present in a concentration effective to reduce frictional forces. The coating mixture is compacted such as by isostatic pressing, formed into strips and then clad to the substrate. One preferred coating contains 0.5 weight percent polytetrafluoro-ethylene in a tin matrix.

Abstract: A process for preparing a permanent magnet is disclosed. The process comprises the steps of exposing material, in particulate form, and having an overall composition comprising 8 to 30 atomic percent of a first constituent selected from the group consisting of rare earth metals, 42 to 90 atomic percent of a second constituent selected from the group consisting of transition metals and 2 to 28 atomic percent of a third constituent selected from the group consisting of substances from Group III of the Periodic Table, to hydrogen gas under conditions such that hydrogen gas is absorbed by the material, exposing the hydrided material, in particulate form, to oxygen or an oxygen-containing gas in an amount and for a period of time sufficient to passivate the material, and compacting the material. Also disclosed are products from this process, namely, passivated, hydrided particles, alloy compacts formed of passivated, hydrided material and permanent magnets, having superior properties.

Abstract: This invention relates to a process for producing a rare earth-containing material capable of being formed into a permanent magnet comprising crushing a rare earth-containing alloy and treating the alloy with a passivating gas at a temperature below the phase transformation temperature of the alloy. This invention further relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material. This invention also relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in water, drying the crushed alloy material at a temperature below the phase transformation temperature of the material, and treating the crushed alloy material with a passivating gas at a temperature from the ambient temperature to a temperature below the phase transformation temperature of the material.

Abstract: A storage cathode comprising a porous, sintered body of a refractory metal is produced by compacting and sintering powder particles of a refractory metal, at least a portion of which are coated, before compacting, with a thin layer of a ductile metal. As a result thereof, it is possible to compact the refractory metal powder, before sintering, at temperatures lower than 600.degree. C., in a non-conditioned space and in an air atmosphere.

Abstract: A partially hardened sintered body such as a rocker arm comprises powder forming a main body and a capsule-like powder composite disposed adjacent to the powder and composed of core particles made of a material harder than the powder and covering particles covering the core particles and made of the same material as the powder. The powder and the capsule-like powder composite are solidified into the partially hardened sintered body.

Abstract: A method for making a resin-bonded magnet of flaky pieces of a ferromagnetic alloy and a resin composition which comprises providing composite granules obtained from a mixture of magnetically isotropic pieces of an Fe-B-R alloy, in which R is Nd and/or Pr, in the form of fine pieces and a resin composition comprised of at least one film-forming polymer having a functional group reactive with isocyanate groups and a blocked isocyanate. The granules are compression molded to obtain a green compact and subsequently thermally treated to allow reaction between the at least one film-forming polymer and the isocyanate by dissociation of the blocking groups by heating, thereby obtaining a resin-bonded magnet.

Abstract: Vias each having no pore are formed in a multilayer ceramic substrate by filling through holes of green sheets with conducting material obtained by: kneading mixed powder particles, the powder particles produced by adding copper oxide powder particles in the amount of 50% (in weight) or less to copper powder particles, with a solution including methyl ethyl ketone and 0.5% (in weight) of isosulfonyltridecylbenzene titanate; drying and cracking the kneaded mixed powder particles, producing cracked mixed powder particles; classifying the cracked mixed powder particles with a 100 mesh filter, producing classified mixed powder particles; spheroidizing the classified mixed powder particles with a collision method performed in gases flowing at high speed; and firing the green sheets at a temperature of about 800.degree. C.

Abstract: A process for producing a rare earth magnet of magnetically improved performance wherein a specific titanate coupling agent is added in one step of the process to enhance the oxidation resistance of the raw materials during production and a special degassing step is incorporated to allow for the removal of the residual titanate coupling agent. The resultant rare earth magnet exhibits improved maximum magnetic energy product ((BH).sub.max) and magnetic coercive force (H.sub.c) as well as other magnetic properties. Rare earth magnet produced by the process is also disclosed.

Abstract: A fully alloyed porous metallic coating is applied to the surface of a metallic prosthetic component by producing a slurry comprising a suspension of the alloy in particulate form in a solution of water containing a film-forming binder material, applying to one or more surfaces of the component a coating of the slurry, forming concave and re-entrant depressions by pressing heat degradable spheres into the coating to promote fixation of the component when in use, heating the slurry to dry the same, and sintering the coated component to bond the particulate alloy onto the component, the spheres burning off during the subsequent heating or sintering step.

Abstract: A method for making metal/ceramic superconductor thick film structures including the steps of preparing a silver/superconductor ink, applying the ink to a substrate, evaporating the ink's binder, decomposing a silver compound in the residue to coat the superconductor grains, sintering the coated superconductor grains, and oxygenating the superconductor grains through the silver coating. The resultant inter-granular silver increases the critical current and mechanical strength of the superconductor.

Abstract: A method for coating the surface of inactive granules comprises dispersing inactive granules having water adsorbed in advance on the surface thereof in a solution having a higher fatty acid and a metal alkoxide dissolved in small amounts in a non-hydrophilic organic solvent thereby forming on the surface of the granules a dense layer of microfine metal oxide powder produced in consequence of hydrolysis of the metal alkoxide.

Abstract: Continuous malleable superconductive material which can be machined, rolled and soldered, being the product of sintering at an elevated temperature and pressure of a metal plated powder of a compound QBa.sub.2 Cu.sub.3 O.sub.7-x wherein Q is yttrium or europium, where x is smaller than one. The metal is advantageously silver and the plating process is one without the use of electricity. A preferred range of silver content is about 5 to 32 weight per cent, and the silver forms an essentially continuous phase in the superconductive material. Sintering can be done at from about 350.degree. and 950.degree. C., with a preferred range of 400.degree. to 900.degree. C. The superconductive material of the invention exhibits transition to zero-resisitivity state and the Meissner effect.

Abstract: A method for fabricating a titanium aluminide composite structure consisting of a filamentary material selected from the group consisting of silicon carbide, silicon carbide-coated boron, boron carbide-coated boron, titanium boride-coated silicon carbide and silicon-coated silicon carbide, embedded in an alpha-2 titanium aluminide metal matrix, which comprises the steps of providing a first beta-stabilized Ti.sub.3 Al powder containing a desired quantity of beta stabilizer, providing a second beta-stabilized Ti.sub.3 Al powder containing a sacrificial quantity of beta stabilizer in excess of the desired quantity of beta stabilizer, coating the filamentary material with the second powder, fabricating a preform consisting of the thus-coated filamentary materials surrounded by the first powder, and applying heat and pressure to consolidate the preform.The composite structure fabricated using the method of this invention is characterized by its lack of a denuded zone and absence of fabrication cracking.

Abstract: A superconductive body of an oxidic superconductive material having good mechanical properties is characterized in that the oxidic material forms a matrix through which finely divided particles are mixed at least the surface of which consists of a metal or a metal alloy. Particles in the form of fibres are preferably used and the surface of the particles consists of silver or gold.

Abstract: A composite material comprising a metal matrix containing tungsten grain is roduced from tungsten powders formed by plasma rapid solidification. The powders comprise tungsten and up to 20 weight percent of a metal selected from the group consisting of molybdenum, tantalum, niobium, rhenium, and chromium. The surfaces of the powders are cleaned to reduce the surface oxide thereon, and the powders are coated with at least one metal selected from the group consisting of copper, nickel, cobalt, hafnium and tantalum. The coated powders are formed into a sintered preform which is less than fully dense, and the sintered preform is further consolidated to full density by a technique selected from hot isostatic pressing, rapid omin-directional compaction, and hot extrusion.

Abstract: Disclosed is a process for obtaining a metallurgical bond between a metal material, or a composite material having a metal matrix, and a metal casting, or a metal alloy casting, which comprises carrying out a surface treatment on said material by means of the deposition of a thin layer of a metal, generally different from the metals contained in the material and in the casting, which is capable of increasing the wettability between the metal of the casting and the material, as well as the heat transfer coefficient between said two partners; and a step of casting around the same material, positioned inside a mold, of the metal, or of the metal alloy the same casting is constituted by.

Abstract: A magnetically anisotropic hot-worked magnet made of an R-T-B alloy containing a transition metal T as a main component, a rare earth element R including yttrium, and boron B; the magnet having fine crystal grains having an average grain size of 0.02-1.0 .mu.m, and having a carbon content of 0.8 weight % or less than an oxygen content of 0.5 weight % or less. The angular variance of orientation of the crystal grains is within 30.degree. from the C axes of the crystal grains when measured by X-ray. This magnet can be produced by mixing the magnet flakes with an additive composed of at least one organic compound having a boiling point of 50.degree. C. or higher.

Abstract: The cathode-forming method involves incorporating cobalt into a nickel plaque so that the exposed surfaces and the pores of the nickel plaque are uniformly covered with cobalt. The plaque is then treated to form nickel hydroxide in the pores and on the surfaces thereof. The cobalt is thus diposed at the interfacial boundary of the nickel plaque and nickel hydroxide so as to reduce the impedance and enhance charge conduction of the cathode. The mode of incorporation can vary. Thus, the sintered nickel plaque can be soaked in an aqueous solution of a water-soluble salt of cobalt, such as cobalt nitrate, then dried and resintered. Another mode involves dispersing a water-soluble cobalt salt in an aqueous slurry of nickel particles and water-soluble binder for the particles. The nickel particles are thus uniformly covered with the dissolved cobalt salt and then are compacted into a plaque. The plaque is dried and finally sintered.

Abstract: Disclosed are a method of and a device for manufacturing Nd-Fe-B alloy magnet materials, and in particular, for manufacturing an integral, columnar-ring-shaped Nd-Fe-B magnet which is multi-pole-magnetized along the circumference thereof and which is used as the rotor magnet of a high-efficiency stepping motor. According to the method, a green compact or a densified compact is first prepared from a selected flake or a powder material composed of amorphous and/or fine-crystallized particles obtained through rapid quenching of the molten alloy. It is then provided with magnetic anisotropy through plastic deformation effected radially inwardly along substantially the entire periphery of the compact initially deformed to receive a mandrel-core, and maintained at a temperature of 600 to 850 degrees C. Subsequently, the deformed body is magnetized with the desired radial or polar magnetization pattern.

Abstract: Provided herein are high-strength high-toughness sintered alloy steel and composite alloy steel powder useful for the production thereof. The sintered alloy steel contains, as the alloy components in the final product, Ni, Mo, and/or W, and C, if necessary, said alloy being composed of 0.50-3.50 wt % of Ni, 0.65-3.50 wt % of Mo+1/2W, (and 0.3-0.8 wt % of C, if necessary), and the remainder of Fe and inevitable impurities, and has a density higher than 7.0 g/cm.sup.3 and a tensile strength higher than 130 kgf/mm.sup.2 after quenching and tempering. The composite alloy steel powder is composed of iron powder particles and powdery alloy components attached by diffusion to part of the surface of the iron powder particles, with the content of Ni and the content of Mo+1/2W in the steel powder of particle diameter smaller than 45 .infin.m being in the range of 2.0-4.2 times the average content in the entire steel powder.

Abstract: Anisotropic hot-worked permanent magnets are made from an R-T-B alloyed powder to which is added a combination internal lubricant including a carbon-based material such as graphite and a glass material such as glass from the B.sub.2 O.sub.3 -SiO.sub.2 BiO.sub.3 glass system. The internal lubricant provides improved formability during the hot-working step, such as die-upsetting, and provides finished magnet products wherein the individual grains are more uniformly plastically deformed throughout the product.

Abstract: The sintered sliding material according to the present invention consists of from 0.1 to 10% by of graphite, from 1 to 7% by of alumina, and balance of copper, and occasionally at least one member selected from the group consisting of from 1 to 10% of Sn and from 1 to 30% of Pb, and/or not more than 1% of P, and includes the alumina dispersed in the copper matrix. The alumina is held by the copper matrix so that the particles of alumina are not separated from the material during sliding under a boundary lubricating condition.

Abstract: A metal-metal matrix composite magnet including a magnetic material such as a neodymium-iron-boron magnetic phase bonded by a metal matrix, preferably copper an a method of making the magnet which involves plating a thin metal layer, for example, a layer having a thickness of less than 1000 angstrom average, from a magnetic phase, pressing the powder, with or without magnetic alignment, into the desired shape and then sintering the pressed powder at a temperature below about 400.degree. C.

Abstract: The present invention relates to porous powder metal (P/M) parts having improved dynamic properties such as impact and fatigue strength. These properties are achieved by the use of finer metal powders.

Abstract: Metallic or ceramic hollow spheres are produced by applying a solid layer to a substantially spherical particle of foamed polymer and the coated polymer cores are pyrolyzed with formation of vapor. In order to permit an economical production of the hollow spheres and a wide selection from a wide range of metallic or ceramic materials, the particles consisting of foamed polymer are treated in a state of agitation with an aqueous suspension which contains dissolved or suspended binder and metallic and/or ceramic powder particles, whereby a coating is formed on said polymer particles. The coating is dried, the polymer particles and least part of the binder are subsequently pyrolyzed at temperatures from 400.degree. to 500.degree. C. with formation of vapor while they are agitated and the resulting metallic and/or ceramic hollow spheres are sintered at temperatures from 1000.degree. to 1500.degree. C. while they are agitated.

Abstract: A method is disclosed for producing metal carbide grade powders, which comprises forming a wax mixture consisting essentially of in percent by weight about 10 to 60 of an organic compound additive which is a solid at room temperature and contains a C.dbd.

Abstract: A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

Abstract: A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

Abstract: Particles are sinter-fused onto the surface of a prosthesis shaft of titanium or titanium alloys. Before sinter-fusing, a coating material which forms below the .alpha.-.beta.-transition temperature a liquid phase with the material of the prosthesis and particles is applied to provide a coating between the shaft and particles.

Abstract: A powder metallurgy produced high speed tool steel article comprising a mixture of prealloyed high speed tool steel particles coated with a hard, wear resistant material, such as a carbide or nitride, mixed with prealloyed high speed tool steel uncoated particles; the particles are compacted to essentially full density and the hard, wear resistant material is at the boundaries of the coated particles and contained in a continuous matrix of the high speed tool steel. The article is produced by hot compacting a particle charge to essentially full density of a mixture of the coated and uncoated particles.

Abstract: The invention provides a tin-containing iron base powder comprising iron base particulates each having tin-rich portions on the surface in which at least a part of the tin forms a compound with iron, wherein the total tin content ranges from 1 to 20% by weight of the powder. The invention also provides a process for making such a tin-containing iron base powder by mixing an iron base powder with a powder tin compound capable of generating metallic tin upon thermal decomposition, and heating the mixture to a temperature of 450.degree. to 700.degree. C. in a reducing or non-oxidizing atmosphere. Using this tin-containing iron base powder as a sintering material, there can be obtained sintered products having a high density and excellent magnetic properties.

Abstract: A process is described in which hollow spheres or hollow-sphere composites (moldings) having high-strength walls are produced. Additional layers are applied to metallized spherical lightweight particles having a core of foamed polymer. In order to increase the strength of the wall of the spherical particle and the strength of the molding, metallized lightweight spherical particles having a metal wall thickness of 5 to 20 microns are treated (coated) with a dispersion of particulate metal or metal oxide or particulate ceramic or refractory material, the lightweight spherical particles coated in a thickness from 15 to 500 microns are dried, the dried particles are heated to a temperature of about 400.degree. C. to effect a pyrolysis of the polymer core, and the particles are subsequently sintered at a temperature from 900.degree. to 1400.degree. C.

Abstract: A method of producing metal-coated abrasive grain granules suitable for the manufacture of metal bonded diamond tools, by the steps of initially preparing a slurry of metal powder with a solution of an agglomerating binder dissolved in an organic solvent, agitating the slurry to homogenously suspend the metal powder therein, and spraying the slurry using an atomizing nozzle into a fluidized suspension of abrasive grains within a fluid bed granulator to progressively build and dry a uniform spherical coating of the slurry on each individual abrasive grain.

Abstract: What is disclosed is an improvement in a method for treating the reaction residue from the preparation of organochlorosilanes or chlorosilanes from the reaction of metallic silicon with a chlorinated hydrocarbon or hydrogen chloride, said method comprising combining the reaction residue with water and granulating the mixture of the reaction residue and water, the improvement comprising (A) coating the resulting granules from the granulating of the mixture of the reaction residue and water with an inert inorganic powder.

Abstract: A method for the assembly and connection of bodies, massive parts or powder grains, of alloys comprising at least 50% of nickel, cobalt or iron, comprises a preliminary operation of deposition at the interface of the said bodies of a product of the type MBF.sub.x, x being equal to 3 or 4, M designating a radical of the type NH.sub.4 giving off when hot a gaseous component such as NH.sub.3 or a metallic element and a sequence of treatment of cleaning/activation by passage of the coated body at a temperature in excess of the temperature of sublimation of the said product.

Abstract: A process for bonding together two or more pieces of material, at least one of which is an amorphous material, wherein an intermediate interlayer is placed between the two pieces and the assembly is hot pressed at a temperature above the melting point of the interlayer but below the crystallization temperature of the amorphous piece. The composition of the interlayer is chosen so that the elements diffusing into the pieces being bonded are compatible with retention of the amorphous structure. When the bonding operation is carried to completion, no evidence of the interlayer as a separate phase remains. Alternatively, the bonding operation may be halted before completion and the interlayer will remain as a separate, observable phase. For bonding hard metal amorphous materials, alloys of aluminum with silver, gold, silicon and germanium, and alloys of gold with silicon, with the addition of fluxing elements such as phosphorus and boron, have been found to provide particularly satisfactory results.

Abstract: The invention relates to a process for the treatment of a metal oxide powder, particularly a UO.sub.2 or PuO.sub.2 powder, with a view to its fritting.This process consists of oxidizing the powder, so as to form on its surface a hydrated oxide layer of the same metal. When the oxide is UO.sub.2 or PuO.sub.2 and mixtures thereof, as well as those prepared with ThO.sub.2, the treated powder can be used for producing nuclear fuel pellets by cold compression, followed by fritting.