Abstract: A fiber optic sign and method of making the same are disclosed. A plurality of fibers are arranged to form a design, preferably by a template, and are then bonded together into a block of glue, epoxy, rubber, or other castable liquid. Arrangement of the fibers is accomplished by placing them on a template and vibrating them until they fall through holes in the template.

Abstract: This invention relates in general to a method for the formation of films having a controlled molecular orientation prepared from rod-like extended chain aromatic-heterocyclic ordered polymers, and containing a binder in the micro-infrastructure. Such films have high tensile strength, modulus, and environmental resistance characteristics.

Abstract: A process to form a body of thermoplastic polymeric fibers and improve the body's resistance to permanent deformation. The vehicle seat component of this invention is compressed twice at progressively greater pressures during the molding process in order to break and reform the bonds between the polymeric fibers.

Abstract: A method of producing a nonwoven mat from recycled carpet. The carpet comprises high and low melting thermoplastic fibers. The method comprises shredding the carpet into pieces, scattering the pieces onto a support web to form a layer and heating at least the surface thereof to affect melting of the lower melting thermoplastic fibers.

Abstract: An improved method of making a more comfortable and easily recyclable body for a vehicle seat component using thermoplastic polymeric fibers is described. This method produces a body of thermoplastic polymeric fibers consisting of zones of different densities.

Abstract: With the method of processing liquids, fine to very fine organic and/or inorganic granular particles are used, whereby pursuant to the invention the particles are mixed and compressed together in a first step to form an agglomerate that is heated at least to a temperature that is near the melting point thereof. The particles are thereby fixed in place by being subjected to a process similar to sintering for a suitable length of time, whereupon the resulting agglomerate is screened, or reduced in size in a grinder, to a granular size that is suitable for an intended use. This enables stabilizing and filtering aids to be produced with predetermined or predictable physical or chemical properties that are suitable for specific processes.

Abstract: A method of producing passive and/or active optical polymer components (10) having vertical coupling structures (45), wherein at least one structure (22) for receiving a light waveguide (40; 46), and at least two fiber guide structures (14) and at least two adjusting structures (36) are produced on a substrate plate (32) and on a lid plate (34) such that both the plate and the lid plate possess fiber guide structures (14) with which the adjusting structures (36) located opposite in the lid plate or substrate, plate respectively are associated after assembly, and wherein the light waveguide structures (22) of the substrate plate (32) and the lid plate (34) which connect the fiber guide structures (14) extend parallel to each other in at least one region (45) such that the optical fields in the respective light waveguides (40) can be coupled with one another.

Abstract: Method for producing an elongated sintered article, characterized by the steps including filling powder material in a pipe, carrying out plastic deformation of the pipe filled with the powder material, and heating the pipe filled with the powder material to burn and/or sinter the powder material.The method of the present invention is advantageously applicable to production of wire or rod of ceramics, particularly so called new ceramics or fine ceramics, sintered alloys or their combination, which are difficult of shaping or moulding by conventional process such as wire-drawing, rolling or extrusion of powder material and are difficult of machining or processing after the powder material is sintered.

Abstract: A smart optical connector (100) sends and recieves optical signals over optical fibers (200, 202). The smart otical connector (100) is capable of converting electrical signals to optical signals for transmission, and capable of converting optical signals to electrical signals for reception. Addtionally, the smart optical connector (100) comprises circuitry (217) for modifying the format of the electrical signals-to provide compatibility between various equiptment (414, 416, 418) which require differing formats.

Abstract: A method for producing an REBaCuO oxide superconductor having large magnetic levitation force, where RE is a rare earth element selected from the group consisting of Y, Sm, Eu, Gd, Dy, Ho, Er, and Yb, involves the steps of using a raw material mixture as the starting feed, heating the raw material mixture for partial melting, followed by cooling and solidification, pulverizing and mixing the resulting solid, shaping the resulting mixture into a given shape, placing or embedding nucleates on or in the resulting shape, followed by heating for partial melting, and cooling the resulting partial melt to a substantial temperature at which a superconducting phase starts to form, followed by slow cooling, whereby the superconducting phase is preferentially formed and grown from a nucleation site.

Abstract: A method for producing a hybrid integrated optical circuit which utilizes a molding tool having holding devices for an electrooptic semiconductor component, negative molds for a waveguide trench and holding devices for an optical waveguide. The holding devices of the molding tool adjust the electrooptic semiconductor component with respect to the negative mold of the waveguide trench during reshaping with a polymer. The basic unit produced consists of the electrooptic semiconductor component, which is adjusted with respect to the waveguide trench molded in the polymer. Adjoining the waveguide trench are holding devices, which are molded in the polymer and by means of which an optical waveguide can be coupled to the waveguide trench in a self-adjusting fashion. The basic unit and the optical waveguide are permanently connected to one another with the aid of a cover, the waveguide trench being filled with an optically transparent material, as a result of which a waveguide is formed.

Abstract: Metal silicide targets are provided for sputtering which have a density of at least 99%, no more than one coarse silicon phase 10 .mu.m or larger in size that appears, per square millimeter, on the sputter surface, and an oxygen content of at most 150 ppm. They are made by a method which comprises finely grinding a synthesized silicide powder, vacuum annealing the finely ground powder in a hot press die without the application of pressure, and thereafter compacting and sintering the compact to a density of at least 99% by hot pressing. Alternatively, the finely ground powder is vacuum annealed as a presintered body at a density ratio of 50 to 75%, and thereafter is compacted and sintered.

Abstract: A method for making a cover for an integrated optical circuit, a cover for an integrated optical circuit, and an integrated optical circuit made with this cover are proposed. The method serves to minimize the effort and expense in integrating optical components in fiberoptical systems. An optical element 29 is placed in a molding die (10) with adjusting elements (13) that adjust the optical component (29) in its position, and a curable liquid is cast all around the optical component (29), and after it solidifies, this liquid forms the cover (25).

Abstract: A vacuum hot pressed alumina material having small, isometric grains; a uniform distribution thereof; relatively low, predominantly transgranular porosity; and a density approaching the theoretical density of pure alumina produced by vacuum hot pressing alumina powder which contains at least 98.0% alumina, is substantially free of any sintering aids or any other additives, and has a median particle size less than about 3 microns, in a vacuum hot press operated at a temperature of at least about 1350.degree. C. and a pressure of at least 28 MPa (3500 PSI) for a sintering period of at least 1.5 hours. The vacuum hot pressed alumina material also has compressive strength, flexural strength, impact strength, and wear resistance superior to that for most conventional sintered alumina materials.

Abstract: A mold arrangement for molding an optodevice onto an optical fibre ribbon. The mould includes several plates which are intended for insertion between the movable top plate and the stationary bottom plate, or counterpressure plate, of a transfer molding press, and includes an inlet channel, primary and secondary runners, and an optodevice molding cavity which is defined by two of the plates, the mould plates, when the mould is closed, and through which the fibre ribbon extends. Each of the mould plates is provided with respective front and back exchangeable jaws. One jaw of the front jaws is provided in the jaw dividing plane with V-grooves which correspond in number to the number of fibers in the fibre ribbon and in which the optical fibers from which a protective covering material has been stripped are positioned so that their centers lie in the jaw dividing plane. That side of the other jaw which lies proximal to the fibers is provided with a recess in which a pad of soft resilient material is mounted.

Abstract: This invention relates generally to a novel directed metal oxidation process which is utilized to produce self-supporting bodies. In some of the more specific aspects of the invention, a parent metal (e.g., a parent metal vapor) is induced to react with at least one solid oxidant-containing material to result in the directed growth of a reaction product which is formed from a reaction between the parent metal and the solid oxidant-containing material. The inventive process can be utilized to form bodies having substantially homogeneous compositions, graded compositions, and macrocomposite bodies.

Abstract: A process for creating a three-dimensional shaped object by providing a container having a fluidized bed of fusable particles therein and a base plate disposed within the particle bed below an upper level of the particles. A heat beam is directed in a desired pattern onto the upper level of particles above the base plate to fuse certain of the particles together to form a formed shape with the base plate then being lowered. A new upper level of fusable particles from the particle bed covers the formed shape, selected of which particles are then heated by the heat beam in a desired pattern to fuse the thus-heated particles to one another and to fuse the particles to the previously fused formed shape of particles with the process continuing until the desired three-dimensional shaped product is formed and removed from the particle bed.

Abstract: A block copolymer is prepared by reacting an aluminumnitrogen polymer and a silazane polymer at a temperature not greater than 400.degree. C. Block copolymers containing alkenyl or alkynyl groups can be crosslinked by supplying energy to generate free radicals, An AlN/SiC-containing ceramic is formed by pyrolyzing the crosslinked block copolymer in a nonoxidizing atmosphere.

Abstract: A method for the production of articles made of a particle-based material; e.g., ceramics and sintered metals. In accordance with one aspect of the invention, a thermally settable slurry containing a relatively high concentration of the particles is introduced into an immiscible, heated fluid. The slurry sets or hardens into a shape determined by the physical characteristics of the fluid and the manner of introduction of the slurry into the fluid. For example, the slurry is pulse injected into the fluid to provide spherical articles. The hardened spheres may then be sintered to consolidate the particles and provide a high density product.

Abstract: In a method for manufacturing fibre-reinforced structures with a glass matrix, there is used for the glass matrix an SiO.sub.2 colloid dispersed in water as glass former, with which the fibres are impregnated, and the impregnated fibres are heated in the final form of the structure to the sintering temperature of the SiO.sub.2 colloid.

Abstract: A process for fabrication of a filler for a ballast container used with frescent lighting employs a mixture of a high-density polyethylene in powdered form (derived from recycled milk containers) and dry sand. After loading the specified mixture into a ballast container to fill the unfilled volume remaining after the ballast container has electrical components installed, a closure means is placed on the loaded and filled ballast container, subsequently heated for a predetermined time period to achieve melting of the specified high-density polyethylene and dry sand mixture. After cooling the melted, high-density polyethylene, the high-density polyethylene and dry sand mixture fuses into a solid mass. A preferred mixture is comprised of a 50/50 weight percent ratio of the specified high-density polyethylene and dry sand.

Abstract: Tough ceramic products can be prepared without exotic pressure fabricating techniques by use of a matrix laminate comprising a continuous fiber ceramic reinforcement in tow or woven form for strength, stiffness, and toughness and a ceramic matrix generally comprising (a) a filler, such as mullite; (b) ceramic reinforcing whiskers, such as silicon nitride or silicon carbide, for fine-scale interlaminar shear resistance (c) a binder, such as colloidal silica; and (d) an activator, such as a trona-like material including sodium and carbonate. The matrix is brushed into the fiber reinforcement, which is then laid up, dried, and cured. Tandem ceramic composites can be fabricated.

Abstract: The present invention relates to a mold for simultaneously molding a plurality of ferrules onto a corresponding number of optical fibers. The mold preferably includes a runner plate, a first cavity plate, a second cavity plate, and a support plate, each of which is to be inserted between a movable top plate and a fixed bottom plate of a transfer molding machine. The plates to be inserted have a vertical inlet channel and primary and secondary runners for distributing molding compound. These runners lead to a plurality of first and second mutually coincidental mold cavities arranged in rows in the first and second cavity plates, respectively. In a preferred embodiment, each of the first and second mold cavities are made up of mutually coincidental, cylindrical coaxial parts and a larger coaxial, cylindrical bore formed in one or both cavity plates. The dividing plane between the first and second cavity plates coincides with the wider bore.

Abstract: A method of producing a patterned shaped article includes the steps of disposing at a prescribed position within a main form for molding the shaped article a cell form having a plurality of cells arranged in a contiguous manner, charging a prescribed amount of dry pattern-course material for forming the pattern course of the shaped article into prescribed cells of the cell form, charging a base-course material for forming the base course of the shaped article into the remaining space of the main form not filled with the pattern-course material, removing the cell form, causing the charged pattern-course material and base-course material to set into a shaped article, removing the shaped article from the main form and, optionally, sintering the shaped article.

Abstract: A process for thermal debinding and sintering of a workpiece made by molding a mixture of a binder and a powder, the process entailing the steps of injection molding a workpiece entailing at least 30% vol. of binder, the binder containing from about 70% to about 90% wt. of at least one wax and from about 10% to 30% wt. of high molecular weight polymer, introducing the molded workpiece in an enclosure at ambient temperature, injecting an atmosphere of at least 95% vol. hydrogen and less than 5% vol. water vapor, heating the enclosure and/or the workpiece until reaching a temperature between about 150.degree. C. to about 200.degree. C., maintaining the temperature during a period of time sufficient to substantially decompose all the waxes in the binder, then heating again the enclosure and/or the workpiece to reach a temperature of about 700.degree. C.

Abstract: An optical/electrical connector including a molded base having a well and a plurality of grooves extending from the well to a first outer edge of the base and alignment guides associated with the grooves at the first outer edge. The base further having external electrical connections with first ends exposed and positioned in the well and second ends extending outwardly beyond a second outer edge of the base. An array of photonic components is positioned in the well and each aligned with a separate groove. The array is electrically coupled to the exposed first ends of the external electrical connections of the base. The grooves are filled with a plastic material to form optical waveguides from the optical ports to the first outer edge.

Abstract: A method of manufacture of a fiberscopic catheter having a tightly fitted optical glass fiber bundle received within an internal lumen of the catheter. The lumen for receiving the optical glass fiber bundle is heated and expanded under internal fluid pressure. The catheter and lumen are then cooled with the lumen still under the internal fluid pressure. After cooling, the fluid pressure is released and the lumen retains its expanded condition. An optical glass fiber bundle is inserted into the expanded lumen to a predetermined position within the catheter. The catheter and lumen are reheated to contract the expanded diameter of the lumen about the optical glass fiber bundle to provide a fiberscopic catheter having a tightly fitted fiber optic bundle within the catheter.

Abstract: The present invention generally relates to manufacturing apparatus, method of manufacture, and products manufactured thereby and more particularly to an integral three-dimensional object (6, 15) formed from individually contoured laminations (4, 62) of the same or gradually varying shape, successive laminae of that object being produced out of thin sheet or powder based materials (1, 60) through the cutting, fusing or physiochemical property changing action generated by a computer directed beam (7) of concentrated energy or matter, successive substantially planar laminations (4, 62) of that object (6, 15) being automatically stacked together for step-wise laminar buildup of the desired object (6, 15).

Abstract: An integrated optical coupler comprises a substrate with fiber-aligning grooves and waveguiding channels and a covering with complementary grooves and, optionally, channels. These couplers can be made from reproducible masters and electroplated molds made from those masters.

Abstract: Porous graphite in solid form is hot isostatically pressed in a refractory metal container to produce a solid graphite monolith with a bulk density greater than or equal to 2.10 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed, chemically vapor deposited, or coated by some other suitable means onto graphite. Hot isostatic pressing at 2200.degree. C. and 30 KSI (206.8 MPa) argon pressure for two hours produces a bulk density of 2.10 g/cc. Complex shapes can be made.

Abstract: A method of covering a substrate surface with a sintered layer comprises the step of loading a powdery raw material in a region of forming a sintered layer on the surface of a substrate, and the step of sintering the loaded powdery raw material so as to form a sintered layer on the surface of the substrate. The powdery raw material contains at least two elements and has a temperature region in which a solid phase and a liquid phase are present together. The liquid phase is wettable with the substrate. The sintering step is performed within a temperature region in which the solid phase and the liquid phase of the powdery raw material are present together.

Abstract: The method of compression molding an article such as a closure wherein a thermoplastic resin is mixed with additives including a metallic pigment additive, extruded through a nozzle, cut by a blade into individual pellets, and each pellet is deposited into the cavity of a mold which is then closed to compression mold the pellet into an article, including the step of adding a blowing agent to the resin prior to extrusion in a quantity sufficient to randomize the metallic particles in the metallic pigment additive such that gaseous bubbles are provided in the extruded melt and that the gaseous bubbles are substantially expelled during the compression molding resulting in an article that is substantially free of blemishes which normally occur. Preferably, the method includes positioning a mixer plate in the path of the resin immediately prior to the nozzle.

Abstract: The process for producing a hard, shapable material with channels for the passage of fluids and which can be reduced in size at their exit points on the surface and which material has a desired bulk density, can be produced in that a cluster of several particles is formed from particles with the aid of a binder and said cluster is brought into the form of a cohesive structure with the aid of a binder in a further working step and the structure has a plurality of interconnected cavities. The porosity of the surface is reduced by breaking down surface clusters into fragments and embedding them in surface openings.

Abstract: A method for manufacturing a preform having steps of obtaining a plastic material by kneading silica powder, a binder, water, and a surfactant, and obtaining a porous preform by extrusion-molding the plastic material.

Abstract: This method teaches how to recover and reuse a powder of a thermally degradable material which is used in a selective laser sintering (SLS) process. To recycle such a laser-sinterable powder successfully in a SLS machine it is protected against degradation by cooling the hot bed while layer-upon-layer (layer-wise) of powder is being sintered, seriatim, to form successive slices fused together to form an article of arbitrary shape (part). The process requires maintaining the powder which has more than 80% of the number of particles <53 .mu.m as a quiescent bed which is nevertheless porous enough to permit flowing a cooling gas downwardly through the bed without disrupting its surface. Since each slice is formed at the surface, and the part, as it is formed, is supported in a well-insulated bed, the powder adjacent the slice is at a much higher temperature than powder in the rest of the bed, which, but for the cooling gas, would get overheated.

Abstract: A new class of composites results from a matrix of fibers, such as fibers of carbon, alumina, ceramics, and aluminosilicates, interwined in a network of fused metal fibers. The composites can be fabricated to have varying surface area, void volume, and pore size while maintaining high electrical conductivity. Composites are readily prepared from a preform of a dispersion of the metal fibers, other fibers, and an organic binder such as cellulose, by heating the preform at a temperature sufficient to fuse the metal fibers and to volatilize at least 90% of the binder. Where a carbon fiber is used, the metal fibers are fused at a temperature causing a loss of less than about 25%, and usually under 15%, by weight of carbon fiber.

Abstract: A method of making a fused polycarbonate pattern for casting alloy structures, particularly gas-turbine blades, or components. A plurality of powder layers are fused together by a laser beam in a layer-by-layer fashion to produce the pattern. A pattern/casting mold is made and the pattern is burned out in a flash flame oven at a temperature ranging from about 1600.degree. F. to about 2100.degree. F. Preferably the burn-out step is conducted in the presence of an air stream so that the polycarbonate pattern is burned out ash free.

Abstract: A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder comprises a plurality of materials having different dissociation or bonding temperatures. The powder preferably comprises blended or coated materials.

Abstract: The occurrence of efflorescence has been reduced or eliminated in ceramic articles formed from a novel vitreously bonded cement-containing composition. The articles also exhibit improved strength, reduced firing shrinkage and increased frost resistance. The articles are produced by combining hydraulic cement containing calcium silicate and/or calcium aluminate components, vitrifiable inorganic powders forming molten liquid-flowing substances, and reactive or sinterable mineral powders selected from the group consisting of magnesium silicates, aluminum silicates and mixtures thereof; combining the ingredients with water to form a mixture; molding the mixture into an article; hardening the article by hydration; and firing the molded article to a maximum temperature of between about 1000.degree. C. to 1400.degree. C.

Abstract: A method of producing high temperature parts by way of relatively low temperature sintering is disclosed. A powder is produced, for example by spray drying a slurry, in which particles of a high temperature material such as a ceramic are partially coated with a low temperature material such as a polymer. The powder is subjected to selective laser sintering, or another heat-based layerwise additive process, to form a green part where the ceramic particles are bound by the polymer. The green part is permeated with a cementing agent having high temperature properties when cured; the cementing agent binds the exposed ceramic surfaces in the green part. The polymer is then removed, leaving the high temperature part. Additional cementing agent, or another high temperature material, may then be added to the part after removal of the polymer.

Abstract: The invention provides a method and apparatus for making an electrochemical cell solid electrolyte holder. A layer of solid electrolyte powder or its precursor is formed around an externally screw threaded mandrel. The powder is pressed to form the holder in a green state with internal threads formed by the mandrel. The mandrel is screwed axially out of the green holder, after which the green holder is sintered. In the apparatus there is a mandrel which has external threads, and a flexible sheath. The mandrel is receivable in the sheath to provide an annular space around the mandrel for receiving a powder to be isostatically pressed by the sheath. The space is provided between the sheath and a mold, but can, instead, be provided between the mandrel and sheath, or between two sheaths between the mold and mandrel.

Abstract: Apparatus for the continuous extrusion of composite solid articles from a substantially uniform mixture of particulate binder material and particulate primary material in which the feed mixture is forced through an extrusion die of substantially uniform cross-section and subject to heat, pressure and cooling which consolidates the feed mixture whereby it emerges from the die as a solid composite article and in which the pressure in the extrusion die is supplied by back-pressuring external of the die.

Abstract: A calcined microsphere of ultrafine bauxite particles having a mean particle size in the range 0.01 to 0.3 micrometers, said microsphere having a particle size less than 30 micrometers and being characterized by a substantially solid form having a pycnometric density substantially falling in the range 3.2-3.0 g/cm.sup.3, a BET surface area substantially falling in the range 0.05 to 0.5 m.sup.2 /g and a crystal grain size less than 4 micrometers, the surface chemistry of the microsphere being modified to enhance the wettability of the microsphere and to improve its ability to bond strongly with matrix materials in use.

Abstract: An oriented shaped article of a calcium phosphate type compound is disclosed, in which at least two crystallographic axes of the primary particles of which the shaped article is composed each is oriented in one direction, respectively, in at least the surface of said article. A sinter of the oriented shaped article and a processes for producing the article and the sinter are also disclosed.

Abstract: A precision cartridge filter having an average filter diameter of 10 .mu.m or less is produced by preparing a web composed of conjugate microfine fibers by a conjugate melt-blowing process, wherein the conjugate microfine fibers have a lower melting point component, a higher melting point component, and a melting point difference between the lower melting point component and higher melting point component of 20.degree. C. or more; followed by heating and molding the web at a temperature greater than or equal to the melting point of said lower melting point component, but less than the melting point of said higher melting point component.

Abstract: The invention provides a method and apparatus for making an electrochemical cell solid electrolyte holder. A layer of solid electrolyte powder or its precursor is formed around an externally screw threaded mandrel. The powder is pressed to form the holder in a green state with internal threads formed by the mandrel. The mandrel is screwed axially out of the green holder, after which the green holder is sintered. In the apparatus there is a mandrel which has external threads, and a flexible sheath. The mandrel is receivable in the sheath to provide an annular space around the mandrel for receiving a powder to be isostatically pressed by the sheath. The space is provided between the sheath and a mould, but can, instead, be provided between the mandrel and sheath, or between two sheaths between the mould and mandrel.

Abstract: A method of manufacturing rotors having helical lands and intermediate grooves wherein a multi-layer rotor body (2) is moulded or otherwise formed on a shaft (1) to only a small degree of accuracy, whereafter an outer layer (3) of polymer-based material is moulded on the rotor body to a high degree of accuracy. For the purpose of eliminating shrinkage-induced distortion of the lands of the rotor body (2) subsequent to applying the outer layer, the rotor body is produced in a multiple of layers (21, 22), by casting or like moulding processes, with each of the body layers having a thickness which is greater than that of the high accuracy outer layer (3).

Abstract: The present invention overcomes the problems caused by certain intergranular phases present during hot pressing. The invention provides a method of removing such problematic intergranular phases while avoiding problems of non-uniformity. In one aspect, the invention encompasses an improvement in a method of sintering a green body by hot pressing, where the green body contains ceramic grains to be sintered and material capable of existing as intergranular phase material during sintering. The improvement embraces hot pressing the body in the presence of a permeable material adapted to receive at least a portion of intergranular phase material as the sintering takes place or after the sintering has been completed.

Abstract: Metal and ceramic particles of various morphologies are clad with a coating from the transistion metal group consisting of silver, gold, copper, nickel, iron, cobalt, aluminum etc., or combinations thereof, to provide improved coated particles for microelectronics or metal matrix composites or other uses. Refractory metal precursor core particles, such as tungsten, molybdenum, niobium and zirconium, as examples, are provided from a composite of tungsten and copper, for example, made by pressurizing and infiltrating or liquid phase sintering of molten copper into a porous tungsten skeleton. Precursor chip particles derived from a tungsten impregnated billet are used as starter particles which may be further enhanced by cogrinding in an attritor ball mill with smaller copper particles to thereby produce an enhanced copper clad-coating of tungsten particles with predetermined percent by weight of copper and tungsten content.

Abstract: A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto each layer of the powder to produce a sintered mass corresponding to a cross-section of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Also disclosed is a method of forming a part by interaction of material in the powder layer with reactants in the surrounding atmosphere, at locations of the powder irradiated by the energy, or laser, beam. The reaction may be nitridation, oxidation or carburization of the powder, with the product being a chemical compound of one or more constituents in the powder with one or more gases in the atmosphere.