Abstract: Ferrous powder particles are coated with vaporized phosphorus in a fluid-bed reactor to obtain homogeneous coatings of phosphorus. The coated powders are useful feed for pressed structural parts, exhibiting improved green density, compressibility and sintered density thus improving magnetic and tensile properties.

Abstract: The present invention concerns a method, according to which powder compositions of iron-based particles are admixed with a thermoplastic material and a lubricant. The obtained mixture is compacted at a temperature below the glass-transition temperature or melting point of the thermoplastic resin and the compacted product is heated in order to cure the thermoplastic resin. Subsequently, the obtained compacted component is optionally heated to a temperature above the curing temperature.

Abstract: A method of fabricating articles, such as prototype parts and prototype tooling for injection molding, is disclosed. The method begins with the fabrication of the article in a "green" state by the selective laser sintering, or another additive thermal process, applied to a composite powder, preferably a powder of metal particles coated with a thermoplastic polymer. Both the green article and also an aqueous emulsion of a thermosetting material are then preheated to a temperature below the glass transition temperature of the thermoplastic polymer, and the green article is then infiltrated with the aqueous emulsion. The thermosetting material may be a thermosetting polymer with an appropriate cross-linking agent, or may be a cross-linking agent that will react with the thermoplastic binder polymer. After infiltration, the article is dried, and a rigid skeleton of a thermosetting material is now present within the structure of the article. Further processing may now be performed.

Abstract: A wire for fabrication of a vibration resistant filament for an incandescent lamp. The wire includes about 0.05-1.00 weight percent lanthanum oxide dispersed in a tungsten matrix and has a microstructure including stringers of fine particles of lanthanum oxide extending parallel to the wire axis. During primary recrystallization of a vibration resistant lamp filament from the filament wire, the stringers produce a microstructure in the filament exhibiting sufficient grain boundary segments extending generally axially along the length of the filament to render the filament resistant to vibration. A method for producing a vibration resistant filament for an incandescent lamp is also disclosed.

Abstract: A thick-film conductor paste and thick-film conductors formed therefrom. The conductor paste is composed of metallic particles coated with a ceramic layer that reduces leaching and solder diffusion into the conductor, thereby improving the reliability of the conductor-solder bond. The ceramic layer may be continuous or discontinuous, and may be applied to some or all of the particles of the conductor paste.

Abstract: A metallic composite solid, containing alloys and/or intermetallics, is formed by compacting at moderate pressure a mixture of powder particles, foils or sheets at a temperature close to room temperature, well below the melting temperature of the constituent components and without the addition of low melting metals such as mercury, indium or gallium acting as a sintering agent. This low temperature consolidation of the powder mixture is enhanced by having the surface oxide of the powder particles removed, prior to consolidation, and/or by coating the particles with an oxide-replacing metal such as silver or gold. The coating process may be replacement reactions, autocatalytic reduction or electrolytic reduction. The composite formation is assisted by the addition of a liquid acid such as fluoroboric acid, sulfuric acid, fluoric acid, adipic acid, ascorbic acid, or nitric acid.

Abstract: A high-temperature YBa.sub.2 Cu.sub.3 O.sub.x superconducting sintered body is produced through wet grain-coating process in which starting grains are soaked in SnI.sub.4 solution, pressed after the removal of solvent and then sintered at a given temperature, and has a critical current density of at least 500 A/cm.sup.2 at 77 K.

Abstract: A method for stress relieving a compression molded magnetic body is provided for purposes of enhancing the magnetic permeability of the magnetic body. The method involves encapsulating ferromagnetic particles with a thermoplastic polymer coating selected from the group consisting of polybenzimidazole and polyimides having heat deflection temperatures of at least about 400.degree. C. which are capable of withstanding elevated temperatures for a duration which is sufficient to anneal the magnetic body formed from the coated metal particles. As a result, the stresses induced in the magnetic core by the compression molding process can be relieved without detriment to the mechanical properties and magnetic characteristics of the magnetic core.

Abstract: Moldable ferromagnetic particles and method of making a magnetizable molding therefrom. The ferromagnetic particles are spray-coated with a slurry comprising insoluble thermoplastic particles suspended in a solution of a soluble polymer to produce a coating on the ferromagnetic particles which comprises a majority of the insoluble thermoplastic particles embedded in a lesser amount of a binder polymer. When compression molded, the insoluble thermoplastic particles form a continuous matrix for the ferromagnetic particles.

Abstract: A method of preparing a metal alloy product from a powder blend. The method comprising: (a) cold pressing a blend to form a compact, the metal blend comprising a metal powder phase and at least one reinforcement phase having a hardness greater than the metal phase; (b) heating the compact to form a preheated compact; and (c) hot working the heated compact. In a preferred method, the powder metal blend comprises 50 to 90 vol. % of an aluminum alloy powder and 10 to 50 vol. % of silicon carbide; the heating of the compact perforated in a nitrogen atmosphere to form a preheated compact; and the extruded hot compact is hot worked. Hot working may take the form of forging, rolling, upset forging, exuding, compacting or other processes known in the art.

Abstract: The invention relates to a method of preparing a composite sintered body having inner and outer portions fitted with each other. The method includes the steps of: (a) preparing an inner powder compact; (b) preparing an outer powder compact; (c) fitting the inner and outer powder compacts with each other so as to prepare a composite powder compact; and (d) sintering the composite powder compact so as to prepare the composite sintered body. The inner and outer powder compacts are respectively selected such that, during the step (d), the amount of growth of the inner powder compact becomes greater than that of the outer powder compact. Each of the inner and outer composite powder compacts is made of one member selected from the group consisting of a wax-type segregation prevention powder mixture and a metal-soap-type segregation prevention powder mixture. At least one of the inner and outer composite powder compacts is made of the wax-type segregation prevention powder.

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: The present invention provides lubricant compositions for the powder metallurgical field. The lubricant compositions contain a solid phase lubricant such as graphite, molybdenum disulfide, and polytetrafluoroethylene in combination with a liquid phase lubricant that is a binder for the solid phase lubricant. The binder can be chosen from various classes of compounds including polyethylene glycols, polyethylene glycol esters, partial esters of C.sub.3-6 polyhydric alcohols, polyvinyl esters, and polyvinyl pyrrolidones. The binder is solubilized in an organic solvent.

Abstract: A powder of diamond or high-pressure phase boron nitride core particles charged into a coating space as it is dispersed, and a precursor of a coat forming substance allowed to contact and/or impinge against the particles in the powder of core particles so that their surfaces are covered with the coat forming substance, thereby preparing coated diamond or high-pressure phase boron nitride particles which are subsequently sintered. The thusly produced diamond of high-pressure phase boron nitride sinter is composed of coated core particles of high performance that are superhard, uniform, dense and sintered firmly, and which have a controlled microstructure.

Abstract: Process of imparting conductivity to a three-dimensional net-shaped porous sheet can be performed efficiently before carrying out electroplating process. Fine metallic powders are applied to the porous sheet made of a foamed sheet, a nonwoven sheet, a mesh sheet or a plurality of sheets layered one on the other, so that a conductive metallic layer is formed on the porous sheet. Then, an electroplated layer is formed on the surface of the conductive metallic layer. The conductive metallic layer remains when the porous sheet burned out. Consequently, a metallic layer of the conductive metallic layer and the electroplated layer forms the metallic framework of the metallic porous sheet.

Abstract: A process for the production of hard materials wherein hard constituent powders are coated with cobalt and/or nickel metal in solution by reducing the metals from a suitable compound such as an oxide, hydroxide or salt with a polyol while keeping the powder in suspension. The polyol functions both as a solvent and a reducing agent at the same time and is present in an amount of at least 5 times more moles polyol than moles metal. There is obtained an even distribution of the cobalt and/or nickel over the surface of the hard constituent powder without the formation of islands of pure metal.

Abstract: The target element (2) is formed from an inorganic compound layer (16) with a melting point above 300.degree. C. deposited on a foam or metallic felt support layer such that the layer of inorganic compound sinks to part of its depth into the support layer to define a composite layer (17). In order to form the target element, a precursor system of the inorganic compound is applied to the support layer, the assembly so formed is subjected to a pressure of between 0.1 MPa and 15 MPa, the resulting assembly is maintained at between 300.degree. C. and 1600.degree. C. and below the melting temperature of the support in order to obtain a sintered assembly. Said assembly is than cooled to an ambient temperature avoiding any sudden cooling. In order to produce the target, the element (2) is glued to a metallic substrate (4) using a conductive adhesive.

Abstract: This invention relates to a method for producing a self-supporting body comprising the steps of:(a) forming a permeable mass comprising at least one solid-phase oxidant selected from the group consisting of the halogens, sulphur and its compounds, metals, metal oxides other than the silicates, and metal nitrides other than those of boron and silicon;(b) orienting said permeable mass and a source of said parent metal relative to each other so that formation of said oxidation reaction product will occur into said permeable mass;(c) heating said source of parent metal to a temperature above the melting point of said parent metal but below the melting point of said oxidation reaction product to form a body of molten parent metal;(d) reacting said body of molten parent metal with said at least one solid-phase oxidant at said temperature to permit said oxidant at said temperature to permit said oxidation reaction product to form; and(e) maintaining at least a portion of said at least one oxidation reaction product

Abstract: To manufacture a reflector formed by a reflective metallic layer on a metallic matrix composite support, a metallic layer having a reflective surface whose shape is at least approximately identical to the required geometrical shape is disposed on a mold surface having a geometrical shape complementary to the required geometrical shape of the reflector. Fibers to constitute the composite support are draped on the metallic layer. They are metallized by the metallic or intermetallic material to form the metallic matrix. This layer and the metallized fibers are subjected to temperature and pressure conditions adapted to press the reflective surface strongly against the mold surface and to cause diffusion welding of the layer with the metallized fibers and of the metallized fibers with themselves so as to integrate the layer to the composite support during consolidation of the latter.

Abstract: A method for preparing deagglomerated fibres and/or particles and for providing the fibres and/or particles with a substantially uniform protective coating, the fibres and/or particles being of a material selected from the group consisting of carbides oxides, nitrides, silicides, borides, metals and graphite, including SiC, TiC, ZrC, WC, NbC, AlN, TiN, BN, Si.sub.3 N.sub.4, MgO, Al.sub.2 O.sub.3, SiO.sub.2, ZrO.sub.2, Fe.sub.2 O.sub.3, Y.sub.2 O.sub.3, steel, tungsten, molybdenum and carbon, the method comprising (a) preparing an inorganic colloid sol, and (b) mixing the fibres and/or particles are deagglomerated and substantially homogeneously distributed. The fibres and/or particles, e.g. SiC whiskers provided with an aluminum oxide coating by treatment with an aluminum hydroxide-based sol, are used for the preparation of metal matrix composite materials, e.g. based on aluminum or an aluminum alloy.

Abstract: It is an object of the present invention to provide a method of producing sintered- or bond- rare earth element.iron.boron magnets obtainable easily and superior in magnetic properties with stable performance. The method of producing sintered rare earth element.iron.boron magnets according to the present invention is characterized by that it comprises steps of mixing in a scheduled ratio an acicular iron powder coated with a coating material, a rare earth element powder coated with a coating material and a boron powder coated with a coating material, and subjecting the mixture to compression molding followed by sintering of the molded mixture in the presence of a magnetic field. The method of producing bond rare earth element.iron.

Abstract: A process of forming a sintered article of powder metal comprising: selecting elemental iron powder; determining the desired properties of said sintered article and selecting, a quantity of carbon, and ferro alloy from the group of ferro manganese, ferro chromium, ferro molybdenum, ferro vanadium, ferro silicon and ferro boron; grinding said ferro alloy to a mean particle size of approximately 8 to 12 microns; introducing a lubricant while blending the carbon, ferro alloy, with said elemental iron powder; pressing the mixture to form the article; and then high temperature sintering the article at a temperature between 1,250.degree. C. and 1,350.degree. C. in a neutral or reducing atmosphere; so as to produce the sintered article of powdered metal; and includes the product formed thereby.

Abstract: Method of distributing and retaining insoluble additive particles uniformly throughout a mass of moldable metal particles. The additive particles are suspended in a solution of a polymeric binder and spray-coated onto the metal particles. When the solvent evaporates, the additives remain glued to the metal particles by the binder.

Abstract: A method of manufacturing an Ni--Al intermetallic compound matrix composite comprising steps of a) providing an aluminum powder, b) providing a reinforced material, c) providing a reducing solution containing a reducing agent and nickel ions to be reduced, d) adding the aluminum powder and the reinforced material into the reducing solution, and e) permitting the reducing agent to reduce the nickel ions to be respectively deposited on the aluminum powder and the reinforced material. Such method permits the Ni--Al, Ni--Al+B intermetallic compound matrix composite to be produced inexpensively/efficiently/fastly.

Abstract: Thick-skinned extruded metal honeycomb structures, and a method and apparatus for making them, are disclosed wherein a plasticized powder metal extrusion batch is extruded though a die assembly comprising a die and annular mask, the mask having a central outlet for extrusion of the skin and honeycomb core and an extrudate reservoir adjacent the central outlet, the die and mask cooperating to form a skinforming gap fed by the die and by the extrudate reservoir, such that batch material supplied from the reservoir and directly from the die combines to form a thickened outer skin which is integral with, and resistant to separation from, the honeycomb core.

Abstract: A method for manufacturing an intermetallic compound comprises (a) preparing a powder, (b) canning said powder in a tube, (c) executing a first heat treatment to said tube-canned powder, and (d) treating said tube-canned powder for obtaining an intermetallic compound. This invention offers a simple, efficient, and inexpensive method for producing an intermetallic compound possessing excellent mechanical properties.

Abstract: A structural member is produced using starting powder consisting of composite particulates each containing AlN grain within its surface covered by an Al layer of a single crystal structure, and Al alloy particulates of a single crystal structure, and then by sintering the Al layers of the composite particulates with the Al alloy particulates. The Al layers and the Al alloy particulates of the single crystal structure have no dislocation fault, crystal grain boundary. etc., produced therein, and for this reason, they have a low chemical activity. Therefore, the Al layers and the like have a characteristic that they are extremely difficult to oxidize. This ensures that the Al layers and the Al alloy particulates can be reliably sintered to achieve the densification of the resulting structural member.

Abstract: The object of the present invention is to provide a method for preparing small-size and large capacity multilayer dielectric powder condensers capable of employing as the inner electrode materials inexpensive copper alloys or nickel alloys.The method for preparing multilayer dielectric powder condensers according to the present invention comprises steps of:providing a fine dielectric powder having a dielectric film on the surface of a metal powder or a semiconductor powder;preparing a pasty material by kneading the dielectric powder with an organic binder;forming a filmy sheet from the pasty material;applying a paste containing a metal powder for forming electrode on the surface of the filmy sheet and drying the applied sheet;piling a plurality of the sheets;placing the piled sheets between thin glass sheets made from a paste prepared by kneading a glass powder and an organic binder and pressing them together; andsubjecting the piled and pressed sheets to a heat-treatment.

Abstract: The object of the invention is to provide a manufacturing method of a complex shaped R--Fe--B type sintered anisotropic magnet improved the moldability of injection molding and preventing the reaction between R ingredients and binder and controlled the degradation of magnetic characteristics due to residual carbon and oxygen. Utilizing the R--Fe--B type alloy powder or the resin coated said alloy powder, and methylcellulose and/or agar and water, instead of the usual thermoplastic binder, it is mixed and injection molded. The molded body is dehydrated by the freeze vacuum dry method to control the reaction between R ingredients and of the R--Fe--B alloy powder and water; furthermore, by administering the de-binder treatment in the hydrogen atmosphere, and sintering it after the dehydrogen treatment, residual oxygen and carbon in the R--Fe--B sintered body is drastically reduced, improving the moldability during the injection molding to obtain a three dimensionally complex shape sintered magnet.

Abstract: A formable composite magnetic flux concentrator is composed of about 65 to 90 percent ferromagnetic material, such as iron powder, and about 35 to 10 percent binder, the binder being a mixture of an epoxy and one or more catalysts. The concentrator is provided in a formable state as a putty-like body which can be worked into any desired shape dictated by the configuration of the induction heating coil used in a particular application.

Abstract: A release agent for producing sintered metal parts using the release agent. The method includes applying a release agent to contacting surfaces of at least two green metal parts, forming an assembly of the parts, sintering the assembly, and separating the parts which are in contact with the release agent. The release agent is a mixture of alumina and a vehicle having a vaporization temperature of less than about 100.degree. C. at atmospheric pressure, and is nonreactive with the alumina and the green metal parts. When at least one of the parts having a contacting surface is a honeycomb structure, the median particle diameter of the alumina is no greater than about 3 micrometers.

Abstract: The present invention addresses problems in the diamond saw blade and segment art. One aspect of the invention comprises a method for making handleable, strong, discrete, metal-clad abrasive pellets. This method comprises the steps of:(a) spraying onto a bed of gas-fluidized abrasive particles a slurry of metallic powder, a binding agent, and a volatile solvent until substantially all the abrasive particles are coated with at least about 20 wt-% of the metallic powder;(b) recovering the metal powder coated abrasive particles; and(c) heating said recovered coated particles under conditions to form a sintered continuous metal coating enveloping said abrasive particles. The resulting sintered metal-clad pellets form another aspect of the invention.

Abstract: A method for heating metal powder, e.g., iron powder, comprises irradiating the powder with microwaves. The powder may be coated with various materials to enhance the heating effects of the microwave. For example, the powder may be coated with a non-emissive material, such as a ceramic material. The powder may also be coated with a dipole material, such as water or plastic, or a dielectric material.

Abstract: A method of manufacturing a shaped article from a powdered precursor, wherein the components of the powdered precursor are subjected to a self-propagating high-temperature synthesis (SHS) reaction and are consolidated essentially simultaneously. The shaped article requires essentially no machining after manufacture.

Abstract: A method is taught for the preparation of ceramic fibers by electrophoretic deposition of metal oxide upon a conductive fiber core, which core may be subsequently removed.

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: A new silicon carbide material is made following a procedure including hot pressing to provide a finished product having a microstructure with an optimal grain size of less than 7 micrometers. The material exhibits a dominant failure mode of intergranular fracture requiring significant energy for crack propagation. The method of manufacturing is cost-effective by allowing the use of "dirty" raw materials since the process causes impurities to segregate at multi-grain boundary junctions to form isolated pockets of impurities which do not affect the structural integrity of the material. End uses include use as optical and electronic substrate materials.

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: There is disclosed a process for preparing a resin composition for powder molding, comprising 50 to 97 wt % of a metal or alloy powder and 50 to 3 wt % of a thermoplastic resin having heat resistance and crystallinity, which process comprises dissolving the thermoplastic resin having heat resistance crystallinity in a solvent and at the same time, dispersing therein at least one metal or alloy powder selected from iron, brass, nickel silver, stainless steel and aluminum, having an average particle diameter of not more than 500 .mu.m to thereby prepare a mixture. In addition, there is disclosed a process for producing a powder molded product which comprises cold compressing molding the above resin composition and then heating the molding at a temperature not less than the melting point of the thermoplastic resin. This powder molded product has excellent dimensional stability against heat, chemical resistance, and mechanical strength.

Abstract: A composite soft magnetic material is produced from soft magnetic metal (e.g., Sendust) particles by coating the particles with a non-magnetic metal oxide (e.g., .alpha.-alumina) in a mechano-fusion manner, or heat treating the particles to form a diffusion layer of .alpha.-alumina thereon, coating the coated particles with a high resistance soft magnetic substance (e.g., ferrite), and sintering the double coated particles under pressure as by hot pressing or plasma activated sintering. It exhibits high saturation magnetic flux density, magnetic permeability, and electric resistivity. The non-magnetic metal oxide intervening between the soft magnetic metal and the high resistance soft magnetic substance is effective in reducing core loss.

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 insulating metal powder particles comprises steps of placing the metal powder particles in a mixing container and adding a monomer in solution to the metal powder particles to form a mixture. The mixture is then stirred to provide an even consistency and is baked to remove solvents. The mixture is then stirred and the monomer is polymerized by exposing the monomer coated carbonyl iron particles to moist gas. The mixture is then ground to form a powder. The powder is suitable for incorporation into plastic resins for subsequent casting to form radio frequency shields having high DC resistance.

Abstract: Oxide-free metallic, alloy or intermetallic compound formed by coating a powder of at least one member selected from the group consisting of elemental metallic, alloy and intermetallic compound with an oxide-replacing metal. The oxide-free compound may be compacted without the addition of a liquid sintering agent and at temperatures below the melting point of the compound, under sufficient pressure to form a uniform, consolidated intermetallic body.

Abstract: The present invention relates to a copper-molybdenum composite material having utility in electrical applica- tions and the process for forming the composite material. The composite material is characterized by a continuous copper matrix having a plurality of discrete molybdenum particles embedded therein. The molybdenum particles have an aspect ratio in the range of from about 1:1 to about 4:1 so as to create a thermal path through the matrix from a first side of the composite material to a second side of the composite material. The resulting composite material exhibits improved through-thickness thermal conductivity as a result of the molybdenum particles being within the aforementioned range.

Abstract: A sintered or bonded permanent magnet formed from a material consisting mainly of iron, particularly a Nd-Fe-B alloy, and having a high corrosion resistance has a surface coated with a resin obtained by the polycondensation of tannic acid, phenols and aldehydes. A bonded magnet is also made from a powder of any such material composed of particles coated with any such resin.

Abstract: In making a dual alloy gas turbine rotor, a plurality of superalloy components are formed to include an airfoil having a directionally solidified columnar grain structure or a single crystal grain structure. A boron-bearing melting point depressant material is applied to the inner surface and a side surface of the components. The components are arranged side-by-side in an annular array with the first side surface of one component juxtaposed to the second side surface of an adjacent component and with the inner surfaces defining a spray-receiving surface. The airfoils extend in a radial axis or direction of the array while the spray-receiving surface extends in a circumferential direction of the article. A sealing member is positioned adjacent an axial end of the array of the components to close off that end and form a spray-receiving cavity. Boron-bearing melting point depressant material is provided between the sealing member and the end of the array.

Abstract: A polymeric coating material is provided for coating powdered materials and, more particularly, for coating powdered metals formed into parts and sintered, such as to form magnetic cores. The thermoplastic material is polyphenylene oxide which, when properly applied to metal particles to form a magnetic core, is characterized by being sufficiently volatile so as to prevent the formation of contaminants or voids within the sintered article which would be detrimental to the physical properties of the sintered article. Moreover, polyphenylene oxide provides sufficient lubrication and adhesion between adjacent metal particles during an initial compaction process so as to sustain the desired shape of the molded article and maximize metal particle density without the use of additional lubricants, thereby preventing the formation of additional contaminants and/or voids within the resultant sintered article from these lubricants.

Abstract: This invention 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. 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. The passivating gas can be nitrogen, carbon dioxide or a combination of nitrogen and carbon dioxide. If nitrogen is used as the passivating gas, the resultant powder has a nitrogen surface concentration of from about 0.4 to about 26.8 atomic percent. Moreover, if carbon dioxide is used as the passivating gas, the resultant powder has a carbon surface concentration of from about 0.02 to about 15 atomic percent.

Abstract: Methods for preparing metallurgical powders containing an organic lubricant are provided. The powders are prepared by wetting a dry admixture of an iron-based powder, at least one alloying powder, and a first organic lubricant with an organic binding agent that is preferably dissolved or dispersed in a solvent. After removal of the solvent, the dried powder composition is admixed with a second organic lubricant.

Abstract: Methods are provided for fabricating a sintered and solid element from an otherwise unsinterable material, utilizing the property of that material that it will form an eutectic composition or alloy with a suitable alloying agent at a temperature which is below the plastic deformation temperature of the material. Discrete particles of the material to be sintered--such as grains or wire pieces--are coated with a thin coating of the alloying agent and are packed into the position where they are to be sintered. Then, the coated grains or wire pieces are heated so that at least the coating and the regions of the grains just below the coating are slowly raised in temperature. Diffusion regions of the alloying agent into the grains of the sinterable material will then occur. Further heating continues so that at least the diffusion regions increase in temperature to just slightly above the eutectic melting point.