Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron nitride material typically resulting in a body comprising a boron-containing compound, a nitrogen-containing compound and metal. The mass to be infiltrated may contain one or more inert fillers admixed with the boron nitride, to produce a composite by reactive infiltration, which composite comprises a matrix which embeds the filler material. The matrix, in a composite body containing filler material, comprises one or more metal, a boron-containing compound and a nitrogen-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal and/or porosity. The mass to be infiltrated can be contained within a refractory vessel having a venting means included therein.

Abstract: This invention concerns a heat treatment method for rare earth type permanent magnets which are primarily of the Nd-Fe-B type. With regard to these permanent magnets, which oxidize rather easily in the air, the alloy is crushed, and either compression formed in a magnetic a non-magnetic field, sintered at 900.degree. to 1,200.degree. C., and then machined into the shape desired, and then solution treated in an atmosphere of oxygen and/or nitrogen at a temperature of 900.degree. to 1,200.degree. C., and then aged at 300.degree. to 900.degree. C. in order that an oxide and/or nitride protective layer of 0.001 to 10 .mu. be formed on the surface of the permanent magnet to prevent corrosion and in order to relieve machining strain.

Abstract: Structural component made of powder metallurgical materials, particularly temperature resistant alloys, nickel base alloys, are produced by injection molding or pressing. The sintering is divided into individual work steps for producing dense and smooth structural components which are true to shape.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron carbide material which may contain one or both of a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron carbide material, boron-containing compound and/or carbon-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.

Abstract: A wear-resistant sintered iron-based alloy and a process for producing the alloy are described, wherein the alloy comprises a first phase having a martensite composition which comprises from 0.5 to 3.0 wt % of Cr, from 0.4 to 1.0 wt % of Mn, from 0.1 to 0.4 wt % of Mo, and the balance of Fe, based on the total amount of said first phase; a second phase having a martensite and Cr carbide composition which comprises from 10 to 20 wt % of Cr and the balance of Fe, based on the total amount of said second phase; and from 1.0 to 2.5 wt % of C, based on the total amount of said alloy; wherein said first phase and said second phase are present as a mixture containing from 10 to 80% by volume of said second phase, based on the total volume of said alloy; and said alloy is substantially free from any residual austenite.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron donor material and a carbon material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron donor material and carbon donor material. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.

Abstract: A composite comprised of a sintered matrix of spinel ferrite and an electrically conductive phase of elemental silver is produced by co-firing a laminated structure of ferrite powder-containing tapes containing a silver metallization-forming material having two end portions wherein only the end portions are exposed.

Abstract: This invention relates to substantially full-dense, near-net shape bodies made of dispersion strengthened copper (D.S.C.) powder and products which are cold formed and/or machined from these bodies, such as resistance welding electrodes. The invention includes processes for manufacturing substantially full-dense, near-net shape, substantially equiaxed bodies from D.S.C. powder.

Abstract: A starting material for injection molding of a metal powder including from 38 to 46% by volume of an organic binder and the balance of spherical iron powder with an average particle size from 2 to 6.5 .mu.m and having high density sinterability at low sintering temperature, and a method of producing a sintered parts by conducting injection molding, debinding and sintering using the above-mentioned starting material in a non-oxidizing atmosphere at a temperature lower than the A.sub.3 transformation point.

Abstract: A manufacturing method for a multilayered ceramic body using Cu, Ni, Co or Fe as a conductor material, and a conductor forming paste of particular composition of CuO, NiO, CoO or Fe.sub.2 O.sub.3 as the main component, the paste being applied to the multilayered body. The manufacturing method comprises: a process of forming the multilayered body with conductor paste of CuO, NiO, CoO or Fe.sub.2 O.sub.3 as the main component and insulating paste formed of glass and/or ceramic, so that a binder is removed from the laminate by heat treatment in an oxidizing atmosphere; a process of heat treatment for reducing the oxide; and a sintering process for sintering the laminate in a nitrogen atmosphere.

Abstract: A method of manufacturing high-zirconium getters that involves hydrogen pulverization of an entire alloy ingot or ingot pieces. The method offers distinct advantages over techniques that use mechanical means of powder production. The method is useful expecially in the manufacture of tough porous getters, of high Zr-content Zr-V alloys that have minor additions of elements such as Fe, Ni, Mn and/or Al.

Abstract: In a method of sintering an injection-molded article of raw material powder and organic binder, the injection-molded article already debinderized is initially heated up to a certain reaction temperature at which residual binder is removed from it. In subsequent decarburizing step, the residual binder is removed from the molded article under atmospheric or reduced pressure, while being supplied with H.sub.2 gas. Thereafter, in a reducing and sintering step, the molded article is heated up to a sintering temperature and is held at this temperature under reduced pressure for a predetermined period, with H.sub.2 gas being supplied. H.sub.2 content of the atmosphere in the decarburizing step is kept higher than that in the reducing and sintering step.

Abstract: A process for producing permanent magnet materials, which comprises the steps of:forming an alloy powder having a mean particle size of 0.3-80 microns and composed of, in atomic percentage, 8-30% R (provided that R is at least one of rare earth elements including Y), 2-28% B, and the balance being Fe and inevitable impurities,sintering the formed body at a temperature of 900.degree.-1200.degree. C.,subjecting the sintered body to a primary heat treatment at a temperature of 750.degree.-1000.degree. C.,then cooling the resultant body to a temperature of no higher than 680.degree. C. at a cooling rate of 3.degree.-2000.degree. C./min, andfurther subjecting the thus cooled body to a secondary heat treatment at a temperature of 480.degree.-700.degree. C.35 MGOe, 40 MGOe or higher energy product can be obtained with specific compositions.

Abstract: Sputtering targets are made by melting at least one rare earth and at least one transition metal to produce an amorphous alloy melt, forming a powder of the alloy in an oxygen free atmosphere, introducing the powdered alloy into a reducing mold, adding a layer of powdered oxygen-getter on top of the powdered alloy, and hot pressing the alloy.

Abstract: A process for making a composite bearing material comprising a steel backed, prealloyed, lead-bronze sintered powder metal matrix whereby the first sinter step includes induction heating the prealloyed powder and steel backing to above 650.degree. C. and thereafter sintering the same at temperatures of about 850.degree. C. in a second sintering furnace. A composite bearing material made by the same process and comprising a lead particle size averaging less than about 8 microns and having no lead islands larger than about 44 microns.

Abstract: A method is disclosed for producing a high hardness refractory metal part, the method comprising hot isostatic pressing a refractory metal part having a density greater than about 98% of the theoretical density in the presence of a pressurizing gas having an atomic size great enough to strain the lattice of the refractory metal at a pressure to exceed the yield strength of the metal to result in the densification of the part to a density of greater than about 98% of the theoretical density. The part is then rapidly cooled. The resulting part has a hardness approaching the hardness of mechanically worked material.

Abstract: A process is disclosed for producing a sheet of tungsten heavy alloy which involves uniformly blending metal powder compnents of the alloy by forming a slurry of the powder components and one or more chemical compounds of at least one of the components of the alloy as an inorganic binder in a liquid medium, the chemical compound being soluble in the liquid medium and capable of being decoposed into one or more of the metal components of the alloy below the melting point of the metal powder components, removing the liquid medium from the powder components and forming a planar cake of the powder components and said inorganic binder, drying the cake, heating the cake to a temperature sufficient to decompose the inroganic binders into their elemental components or oxides, followed by heating the cake in a reducing atmosphere at a temperature sufficient to reduce any oxides forming during the previous steps to the metals, and sintering the cake to a density equal to or greater than about 90% of the theoretical den

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal with a boron source typically resulting in a composite comprising a parent metal boride and metal. The mass to be infiltrated may contain one or more inert fillers admixed with the boron source to produce a composite by reactive infiltration, which composite comprises a matrix of metal and parent metal boride embedding the filler. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal and/or porosity.

Abstract: There is provided a process for infiltrating a compacted ferrous powder metal body with copper or a copper alloy which process is characterized by presintering the ferrous metal body at a temperature of from about 1875.degree. F. to a temperature below the melting point of the infiltrant, and then in the same furnace, raising the temperature above the melting point of the copper or copper alloy infiltrant for a period sufficient to infiltrate the powder metal body. This process is more economical than the prior double run infiltration processes and provides excellent impact strengths and tensile strengths.

Abstract: Reactive sintering process for producing a shaped body containing the nickel aluminide compound Ni.sub.3 Al, which comprises sintering a compacted shaped mass containing an intimate mixture of substances, e.g. including elemental nickel powder and elemental aluminum powder in a stoichiometric atomic ratio generally corresponding to the compound Ni.sub.3 Al, by heating the mass, e.g. in a vacuum, to an elevated sintering temperature, e.g. 500-750.degree. C., sufficiently to initiate an exothermic reaction, and at a heating rate sufficiently for consequent progressive generation of a transient liquid below the melting point of the aluminum powder and at the corresponding eutectic temperature, and upon initiation of the exothermic reaction continuing the sintering sufficiently to form a densified shaped body containing the nickel aluminide compound Ni.sub.

Abstract: In a method of producing a composite material for a sliding member having a sliding portion and a backing material which supports the sliding portion, the method comprises the steps of: disposing a powder or a sheet material for the sliding portion on the backing material; irradiating the powder or sheet material with laser beam or electron beam; melting or partially melting the beam-irradiated powder or sheet material; and quenching and solidifying the melted or partially melted portion, whereby the particles of the powder are integrated with one another and the powder in contact with the backing material are bonded thereto, or whereby the sheet material in contact wiht the backing material are bonded thereto.

Abstract: The weapon barrel comprises a liner and at least one jacket tube. The liner is made of a highly wear-resistant material, like a cobalt or nickel base alloy, and the jacket tube is made of a tough alloy, like steel. In the manufacturing process the liner material is packed into the jacket tube in the form of a powdery material which may be pre-pressed or pre-sintered. The packing is arranged such as to leave a central free space in the jacket tube, and the jacket tube may be surrounded by an encapsulating tube. The jacket tube or the encapsulating tube is closed either before or after evacuation, and the closed tube arrangement is subjected to a combined heat and pressure treatment at temperatures of at least 900.degree. C., but below the melting point of the relevant materials and at pressures of at least 900 bar. The compound body thus obtained is formed with a full-area metallic bond between the liner and the jacket tube.

Abstract: An aluminum matrix composite containing evenly dispersed reinforcement particles in the aluminum matrix wherein the contents of oxygen and carbon are controlled so that their volume percentage is not larger than 20% and wherein the contents of the reinforcement particles, oxygen and carbon are controlled so that their volume percentage is not larger than 40%. The control of oxygen and carbon is effected by carrying out the main process at a non-oxidizing atmosphere and minimizing the addition of an anti-seizure agent required to facilitate the mechanical alloying treatment.

Abstract: This invention provides a shaped, graded, cermet article comprising at least one continuous ceramic phase and at least one discontinuous metal phase, the ratio of ceramic/metal being controlled and varied over the thickness of the article. The ceramic phase preferably is microcrystalline.

Abstract: A method of producing ferrous sintered alloys comprises the steps of preparing mixed alloy powder containing Fe-P-C eutectic alloy powder which includes phosphorus within the range of 2.0% to 3.0% by weight, carbon not more than 4.0% by weight and one of molybdenum within the range of 8.0% to 11.0% by weight and boron within the range of 0.5% to 3.0% by weight, graphite, and ferroalloy powder containing chromium within the range of 11% to 14% by weight; causing the mixed alloy powder to be subjected to compression molding to have a green compact; and sintering the green compact to have a ferrous sintered alloy containing compound carbides in a matrix structure thereof. The graphite is so selected that the sum total of the graphite and the carbon included in the Fe-P-C eutectic alloy powder constitutes a part within the range of 5% to 8% by weight of the sum total of the graphite and the Fe-P-C eutectic alloy powder.

Abstract: A valve-seat insert for internal combustion engines comprises a double-layered, sintered alloy composed of a valve-seat layer on which a valve is seated, and a base layer integrated with the valve-seat layer and adapted to be seated in a cylinder head of an engine. The valve-seat layer is composed of a sintered alloy of a high heat resistance and a high wear resistance having a composition comprising, by weight, 4 to 8% Co, 0.6 to 1.5% Cr, 4 to 8% Mo, 1 to 3% Ni, 0.3 to 1.5% C, 0.2 to 0.6% Ca, and the balance of Fe and inevitable impurities, the additives, Co, Cr and Mo being present mainly in a form of a Co-Cr-Mo hard alloy and a hard Fe-Mo alloy dispersed in the Fe matrix. The base layer is composed of a sintered alloy of a higher heat resistance and a higher creep resistance than those of the valve-seat layer and having a composition comprising, by weight, 11 to 15% Cr, 0.4 to 2.0% Mo, 0.05 to 0.3% C, and the balance of Fe and inevitable impurities.

Abstract: A copper or copper alloy infiltrated ferrous powder metal part, and method for making the same, characterized as having after infiltration an overall density of at least 7.50 g/cm.sup.3 and a diffusion depth of copper into the steel matrix of less than about 4 micrometers as determined by chemical etching or less than about 8 micrometers as determined by electron dispersive X-ray analysis (EDXA), wherein said ferrous metal is plain carbon steel having a combined carbon content in the range of about 0.15% to about 1.25%, or a low alloy steel.

Abstract: A method for utilizing a powder metallurgy ("P/M") slurry by employing water atomized metallic powders and subsequently reducing the oxide levels therein to acceptable levels. The slurry comprises a carbon containing binder. The slurry is consolidated and sintered under controlled conditions to reduce the oxide levels.

Abstract: A method of sintering compacts of metals, ceramics and the like in powder form. At least the surface portion of the compact is sintered in a plasma atmosphere having a pressure of 10 Torr or less thereby eliminating the open voids and then the compact is subjected to a hot isostatic press process.

Abstract: When a composite nitride obtained by nitriding a fine powder of an alloy comprising metallic silicon and a metal of the group IIIa of the Periodic Table is sintered, a highly homogeneous silicon nitride sintered body having a high strength can be obtained. This fine powder of the alloy and this composite nitride exert a function of promoting sintering of Si.sub.3 N.sub.4.

Abstract: A method is disclosed for preparing a dimensionally stable electrode structure, particularly nickel-chromium anodes, for use in a molten carbonate fuel cell stack. A low-chromium to nickel alloy is provided and oxidized in a mildly oxidizing gas of sufficient oxidation potential to oxidize chromium in the alloy structure. Typically, a steam/H.sub.2 gas mixture in a ratio of about 100/1 and at a temperature below 800.degree. C. is used as the oxidizing medium. This method permits the use of less than 5 weight percent chromium in nickel alloy electrodes while obtaining good resistance to creep in the electrodes of a fuel cell stack.

Abstract: The powdered material contains oxygen in the oxide and/or adsorbed form and the oxygen present is reduced in a first pre-sintering stage and the cohesion of the material is ensured in a second sintering stage. The pre-sintering stage is carried out under a reducing atmosphere based on hydrogen and neutral gas whose flow rate F.sub.G is higher than or equal to: ##EQU1## in which relation: S.sub.P =section of the layer of powder to be sintered in sq.mD.sub.P =voluminal mass of the powder in kg/cu mX(O.sub.2)i=percentage of oxygen mass in the powder before the pre-sintering stage, in the oxide and/or adsorbed form,P(H.sub.2)i=voluminal percentage of hydrogen in the gas introduced into the furnace,P(H.sub.2)f=the smallest voluminal percentage of hydrogen in the atmosphere in the furnace at a point where the oxides have been completely reduced,v.sub.S =speed of feed of the material in the furnace expressed in m/hr,.alpha. is a constantF.sub.G being expressed in cu.m/hr.

Abstract: A manufacturing method of super-heat-resisting alloy material characterized in comprising the steps of: (1) filling and sealing the powder of Ni-based super-heat-resisting alloy in a rubber mold; (2) subjecting the powder in the rubber mold to cold isostatic pressing; (3) sintering the compact in vacuum or in gas atmosphere at a temperature of 1000.degree. C. or more so that the sintered density increases to 95% or more than the theoretical density; and (4) next, subjecting the sintered compact to hot isostatic pressing.

Abstract: A method is disclosed for manufacturing a reaction sintered composite article which comprises at least one ceramic component. The method comprises preparing a particulate mixture of precursor powders leading to the formation of said composite material upon reaction sintering, pressing said particulate mixture to a self-sustaining body, heating said body up to a temperature below the temperature at which the reaction sintering is initiated, comminuting the heat treating body, selecting particles of a suitable grain size distribution, pressing said particles into shapes of desired size and configuration, and heating said shapes up to a temperature at which the reaction sintering is initiated. The reaction sintered body comprises borides, carbides, nitrides or silicides of a transition metal of the groups IVb, Vb or VIb of the periodic table (comprising titanium, hafnium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten), and a metal oxide.

Abstract: A sintered tungsten carbide material and method for manufacturing same in which the method includes the steps of combining metal particles composed of from 75 to 95 percent by weight of a composition containing at least 70 percent by weight of tungsten carbide and from 5 to 25 percent by weight of a binder metal composition, the binder metal composition consisting essentially of from 5 to 15 percent by weight of chromium and from 85 to 95 percent by weight of nickel; pressing the metal particles into a pressed body; sintering the pressed body in a sintering chamber for a period ranging from 20 to 200 minutes, at a temperature ranging from 1400.degree. to 1500.degree. C., and in a protective atmosphere which is one of a vacuum, a noble gas, a mixture of noble gases, and hydrogen gas to form a sintered body; and treating the sintered body for a period ranging from 20 to 200 minutes, at a temperature ranging from 1300.degree. to 1400.degree. C.

Abstract: Discrete copper-nickel-tin spinodal alloy articles, such as bearings, containing from about 5 to about 35 wt. % nickel, from about 4 to about 13 wt. % tin and the balance copper are produced by processing a prealloyed alloy powder to form a green body having substantially the desired shape of, and proportionally sized to, the final article and sintering the green body in a reducing atmosphere or a vacuum at a temperature of at least 1650.degree. F. for sufficient time to achieve at least 90% of the theoretical density. The green body may be formed by either compaction or injection molding of the prealloyed powder. The resulting sintered article may be age hardened to effect a spinodal decomposition of the copper-nickel-tin alloy. The age hardened articles exhibit excellent strength properties and homogeneity while retaining significant ductility.

Abstract: Ag-SnO system alloy electrical contact materials. The Ag alloy before internal oxidation thereof contains Sn of an amount of 5-20 weight %, 0.5-15 weight % of which amount is in the powder form of SnO.sub.2. The existence of SnO.sub.2 particles in the alloy accelerates the internal oxidation speed, allowing oxygen to readily pass aside and between the particles, while the internal oxidation per se makes the alloy more dense by eliminating spaces between SnO.sub.2 grain particles on account of the volumeric expansion of Sn which results from the internal oxidation thereof.

Abstract: A process for the sintering of silicon carbide refractory or ceramic articles using plasma arc gases. In the process of the invention, a formed silicon carbide article is heated in a plasma fired furnace to a sintering temperature of between 2000.degree. C.-2500.degree. C. at a heating rate of 300.degree. C./hr-2000.degree. C./hr, and held at the sintering temperature for 0.1-2 hours. The enthalpy of the plasma gas is 2000 BTU/lb-4000 BTU/lb, when nitrogen is used as the plasma gas. The total cycle time for the process of the invention, including cooling and loading, is 1.5-20 hours. Silicon carbide articles, produced in accordance with the invention, have high strength, high density, high corrosion resistance and high dimensional stability.

Abstract: A three step process in which a metal alloy selected from a tungsten based alloy and molybdenum based alloys is provided to prevent the decarbonization of the alloys. The process involves a three step sintering process wherein the atmosphere during the initial heating step is a mixture of carbon monoxide and hydrogen, thereafter at a intermediate temperature range the atmosphere is hydrogen and a final heating step at a elevated temperature is employed and the atmosphere is a mixture of inert gas and a source of carbon.

Abstract: There is disclosed a process for forming a wear-resistant, sintered layer on a metallic substrate. The process comprises steps of adhesively attaching to a surface of metallic substrate an alloy particle sheet containing 94 to 99 weight % of ternary eutectic alloy particles and 6 to 1 weight % of acryl binder, heating in a non-oxidating atmosphere to a temperature of 150.degree. to 380.degree. C. and holding at the temperature for at least 5 minutes, and heating a sintering temperature of the alloy particles.

Abstract: A method of manufacturing a porous body using particulate material as a starting stock. The particles are inserted in a can, the can evacuated and inert gas admitted to a predetermined back-fill pressure. After hot isostatic pressing, the compact so formed is cooled and subsequently heat treated to permit the pores formed in pressing to expand and form a porous body.

Abstract: A system to prevent, retard or reverse the decomposition of silicon carbide articles during high temperature plasma sintering. Preferably, the system comprises sintering a silicon carbide refractory or ceramic green body in a closed sintering environment, such as a covered crucible, with strategic placement of the plasma torch or torches, exhaust outlet and crucibles. As sintering proceeds, a silicon vapor pressure builds up within the crucible, retarding the decomposition of the silicon carbide body. The plasma torch, exhaust outlet, and crucibles are positioned so that buoyant convective flow is maximized to increase the heat transfer and energy efficiency. In another embodiment, a "sacrificial" source of silicon carbide is placed into the sintering furnace. The silicon carbide in the sacrificial source starts to decompose before the silicon carbide refractory or ceramic article, creating a supersaturated atmosphere of silicon vapor species in the furnace.

Abstract: An improved fabrication process for cobalt-enriched cemented carbide substrates is disclosed, in which an article is generally comprised of tungsten carbide, cobalt, and carbides, nitrides or carbonitrides of titanium, tantalum, and niobium, or mixtures thereof. In one aspect of the invention the article is contacted with nitrogen gas and then sintered in the absence of nitrogen gas to form a cobalt-enriched, B-1 phase-depleted zone. The article is then sintered in nitrogen gas to form a B-1 phase enriched layer on the surface of the article. Additionally, a metal oxide wear layer can be provided on the article.

Abstract: A method is disclosed for making a fuel pellet for a nuclear reactor. A mixture is prepared of PuO.sub.2 and UO.sub.2 powders, where the mixture contains at least about 30% PuO.sub.2, and where at least about 12% of the Pu is the Pu.sup.240 isotope. To this mixture is added about 0.3 to about 5% of a binder having a melting point of at least about 250.degree. F. The mixture is pressed to form a slug and the slug is granulated. Up to about 4.7% of a lubricant having a melting point of at least about 330.degree. F. is added to the granulated slug. Both the binder and the lubricant are selected from a group consisting of polyvinyl carboxylate, polyvinyl alcohol, naturally occurring high molecular weight cellulosic polymers, chemically modified high molecular weight cellulosic polymers, and mixtures thereof. The mixture is pressed to form a pellet and the pellet is sintered.

Abstract: A method of manufacturing a cermet having high toughness and high hardness, which exhibits excellent impact resistance and wear resistance when used in cutting tools. A mixed powder is prepared which consists essentially of: titanium nitride, from 25 to 50 percent by weight; titanium carbide, from 10 to 30 percent by weight; at least one selected from the group consisting of tantalum carbide, niobium carbide, and zirconium carbide, from 5 to 25 percent by weight; tungsten carbide, from 10 to 25 percent by weight; and at least one selected from the group consisting of Co and Ni, and Al if required, from 7.5 to 25 percent by weight in total. The above mixed powder is compressed into a green compact. The green compact is sintered in a nitrogen atmosphere under a pressure within a range from 0.1 to 100 torr, and at a temperature within a range from 1400.degree. to 1550.degree. C.

Abstract: A system for automatically consolidating a plurality of metallic or ceramic (or mixtures thereof) powder preforms is disclosed. The system comprises an assembly container wherein a consolidation container is filled with hot consolidation particles for facilitating the consolidation, and a hot preform to be consolidated thereby. The atmosphere of the assembly container is maintained hot and inert or reducing during assembly of the consolidation charge. Further disclosed are means for automatically delivering the consolidation containers, consolidation particles and preforms to the assembly container. The system includes means for conveying the consolidation containers to a press for consolidation, for separating the containers from the consolidation particles and consolidated preform after pressing, and for recycling the consolidation particles and consolidation containers.

Abstract: An electrical contact formed of a mixture of finely divided electrically conductive metal doped with graphite or cadmium oxide. A thin coating of the electrically conductive metal is disposed upon the side of the contact which is adapted to be welded or brazed to an electrically conductive support. The electrical contact is made by mixing the finely divided cadmium oxide and pressing the mixture into a desired shape. A slurry of conductive metal is then sprayed on one side of the contact. After coating, the contact is sintered at a temperature less than the melting point of the electrically conductive material, whereby the contact is formed and the coating is firmly attached to it. The invention is particularly useful with silver or copper-based electrical contacts.

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.

Abstract: A refractory hard metal-metal composite is formed by impregnating a porous refractory hard metal article with molten metal.

Abstract: A process for producing readily sinterable aluminum nitride powder, which comprises mixing(i) alumina powder and/or powder of a compound capable of forming alumina by heat treatment,(ii) carbon powder and/or powder of a compound capable of forming carbon by heat treatment, and(iii) powder of at least one compound selected from the group consisting of alkaline earth metal oxides, compounds capable of forming said alkaline earth metal oxides by heat treatment, rare earth element oxides and compounds capable of forming said rare earth element oxides by heat treatment,and calcining the resulting mixture in a nitrogen-containing non-oxidative atmosphere, provides an aluminum nitride powder which is readily sinterable without further mixing with a sintering aid.