Addition Of Fugitive Material Patents (Class 419/36)
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Patent number: 6290744Abstract: A sinter of noble metal produced by forming in a required shape or attaching to a given object a plastic art grade clayish composition or adhesion composition comprising a noble metal powder containing at least one member selected from the group consisting of pure noble metal powders and noble metal alloy powders, 0.022-3.0 wt. % of a water-soluble cellulose type resin, 0.02-3.0 wt. % of starch, or 0-0.5 wt. % of a reticular macromolecular substance formed by condensation of a component unit having phenyl propane as a backbone as an organic type binder, and water, drying to hardness the shaped composition or adhering composition, and sintering the hardened shaped composition or adhering composition at a temperature in the range of from the melting point of the noble metal and 70° C. lower than the melting point. A method for the production of the sinter of noble metal. A sinter of noble metal and an attached sinter of noble metal.Type: GrantFiled: November 19, 1999Date of Patent: September 18, 2001Assignee: Aida Chemical Industries Co., Ltd.Inventors: Atsushi Fujimaru, Katsuhiko Shimamoto, Hitoshi Araki, Makoto Miyata
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Patent number: 6284192Abstract: A method of extruding an electrode, batch material, particularly a zinc or nickel, electrode material, and an extruder assembly for extruding the material, are described. The method and extruder are designed to produce a low compaction of the material and low, back pressure, whereby working of the batch material is limited.Type: GrantFiled: October 28, 1999Date of Patent: September 4, 2001Assignee: Corning IncorporatedInventors: Everett W. Coonan, Paul D. Frayer, Roy J. Monahan, Kathleen A. Wexell
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Patent number: 6284191Abstract: A powder metallurgical process of preparing iron aluminide useful as electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 20 to 32% Al, and optional additions such as ≦1% Cr, ≧0.05% Zr or ZrO2 stringers extending perpendicular to an exposed surface of the heating element, ≦2% Ti, ≦2% Mo, ≦1% Zr, ≦1% C, ≦0.1% B, ≦30% oxide dispersoid and/or electrically insulating or electrically conductive covalent ceramic particles, ≦1% rare earth metal, ≦1% oxygen, and/or ≦3% Cu.Type: GrantFiled: September 20, 1999Date of Patent: September 4, 2001Assignee: Chrysalis Technologies IncorporatedInventors: Seetharama C. Deevi, A. Clifton Lilly, Jr., Vinod K. Sikka, Mohammed R. Hajaligol
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Patent number: 6280683Abstract: Improved methods for coating particulate materials at low shear conditions and preferably below the melting point of the coating material are provided. In one aspect, metallurgical compositions are provided that contain a metal-based powder bound to an alloying powder or powders by way of a low melting polymer or wax binding agent, which is preferably polyethylene. The binding agent is blended with the metal-based and alloying powders at elevated temperatures preferably below the melting point of the binding agent. The bonded metallurgical composition can be used in compaction processes to manufacture compacted parts that can be sintered to impart strength.Type: GrantFiled: October 22, 1999Date of Patent: August 28, 2001Assignee: Hoeganaes CorporationInventors: William Hendrickson, Sydney Luk
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Patent number: 6268412Abstract: Molding compositions for shaping parts from stainless steel powders are disclosed. The process comprises the steps of forming a mixture comprising stainless steel powder, a gel-forming material having a gel strength, measured at a temperature between 0° C. and about 30° C. and a gel comprising about 1.5 wt % of the gel-forming material and water, of at least about 200 g/cm2, and water, and molding the mixture at a temperature sufficient to produce a self-supporting article comprising the powder and gel. The preferred gel-forming material is an agaroid and the preferred molding process is injection molding.Type: GrantFiled: May 12, 2000Date of Patent: July 31, 2001Assignee: Rutgers, The State University of New JerseyInventors: Michael Sean Zedalis, Rick Duyckinck, Brian Snow, Anthony Fanelli, Joan Virginia Burlew
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Patent number: 6261496Abstract: A novel process for preparing injection molding feedstock compounds in a continuous manner amenable to high volume manufacturing includes the steps of forming a mixture including metal and/or ceramic powders, a binder and a liquid carrier, supplying the components in a continuous manner to a twin screw extruder, forcing the homogeneous compounded mixture through an exit die, and cutting the extruded strand into pellets. The pellets are useful for shape-forming articles by various molding processes.Type: GrantFiled: July 15, 1999Date of Patent: July 17, 2001Assignee: AlliedSignal Inc.Inventors: Richard L. Duyckinck, Brian Snow, Steven Sesny, George Glandz
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Patent number: 6261336Abstract: A composition for forming molded metal containing articles having improved stability. More particularly, a corrosion resistant composition for forming injection molded articles having a sodium silicate corrosion inhibiting additive. The corrosion inhibitor prevents metal oxidation when a metal containing powder is mixed with a water based binder, providing stability to the article and preventing generation of hydrogen gas. This significantly enhances the shelf life of the moldable composition prior to molding.Type: GrantFiled: August 1, 2000Date of Patent: July 17, 2001Assignee: Rutgers, The State University of New JerseyInventors: Mohammad Behi, Jerry C. LaSalle, George A. Glandz
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Patent number: 6261514Abstract: The invention concerns a method of preparing sintered products having high tensile strength and high impact strength comprising the steps of forming a mixture by mixing an iron powder including 1-4% by weight of Cr, 0.2-0.8% by weight of Mo 0.09-0.3% by weight % of Mn, less than 0.01% of C, less than 0.25% by weight of O, 0-1.2% of graphite, a high temperature lubricant and optionally an organic binder; preparing a heated powder composition by heating the mixture to a temperature above ambient temperature; transferring the heated powder composition to a preheated die; forming a compacted body by compacting the heated powder composition in the die at an elevated temperature; and forming a sintered product by sintering the compacted body at a temperature of at least 1220° C.Type: GrantFiled: May 31, 2000Date of Patent: July 17, 2001Assignee: Höganäs ABInventors: Caroline Lindberg, Johan Arvidsson
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Patent number: 6254998Abstract: A method for making foam structures suitable for use as mechanical energy absorbers, structural members, filters, catalyst carriers or the like. A composite rod comprising an outer shell and an inner core is formed of respective mixtures of powders. The mixture for the outer shell comprises a sinterable powdered structural material such as ceramics, metals, intermetallics, and a powdered binder such as paraffin, wax or polymer. The inner core comprises a powdered channel-forming filler material such as melamine or polymers, or soluble inorganic compounds or a metal that can differentially be removed from the structural material of the shell. The composite rod may be formed by extrusion. The composite rod is sectioned into a plurality of composite rod segments of predetermined length and a plurality of these segments is assembled in randomly oriented relationship to one another. The assemblage of rod segments is then consolidated, and the binder and filler are then removed, as by heating.Type: GrantFiled: February 2, 2000Date of Patent: July 3, 2001Assignee: Materials and Electrochemical Research (MER) CorporationInventor: Lev J. Tuchinsky
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Patent number: 6251340Abstract: An improved system for forming a three-dimensional object by filament deposition of forming materials includes a crucible for holding a reservoir of the filament forming material, an orifice disposed in the bottom of the crucible through which the forming material passes to form a flow of material filaments, and a flow control apparatus for controlling and selectively depositing the flow of material filaments on the substrate exclusively where required to form the three-dimensional object. In a preferred embodiment, the forming material is ejected from the crucible as a variable-diameter circular liquid jet, which cools to form variable-diameter filaments of semi-molten forming materials.Type: GrantFiled: April 13, 2000Date of Patent: June 26, 2001Assignee: Arizona State UniversityInventor: Ampere A. Tseng
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Patent number: 6228299Abstract: A gelcasting composition has improved drying behavior, machinability and shelf life in the dried and unfired state. The composition includes an inorganic powder, solvent, monomer system soluble in the solvent, an initiator system for polymerizing the monomer system, and a plasticizer soluble in the solvent. Dispersants and other processing aides to control slurry properties can be added. The plasticizer imparts an ability to dry thick section parts, to store samples in the dried state without cracking under conditions of varying relative humidity, and to machine dry gelcast parts without cracking or chipping. A method of making gelcast parts is also disclosed.Type: GrantFiled: August 17, 1999Date of Patent: May 8, 2001Assignee: UT-Battelle, LLCInventors: Mark A. Janney, Claudia A. H. Walls
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Patent number: 6224823Abstract: The invention relates to a process for producing sinterable metallic shaped parts from a metal powder, which is mixed with an auxiliary compacting agent containing at least in part components from the polyalkylene glycol family, is filled into a compacting mold and, following the compacting under pressure, is ejected from the mold as compacted shaped part.Type: GrantFiled: July 27, 1999Date of Patent: May 1, 2001Assignee: GKN Sinter Metals GmbH & Co. KGInventors: René Lindenau, Klaus Dollmeier, Wieland Kynast, Jens Wahnschaffe
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Patent number: 6207101Abstract: A fired body and method of making involves compounding powder, binder, aqueous solvent for the binder, surfactant, and non-solvent with respect to at least the binder, the solvent, and the powder, with the addition of an organosilicon compound. The non-solvent is lower in viscosity than the binder combined with the solvent, and the amount of solvent is less than the amount that would be used absent the non-solvent. The components are mixed and plasticized and then shaped into a green body, which is then fired to produce the product body. The organosilicon compound enhances the stiffness in the green body afforded by other non-solvents, and results in increased strength and reduced cracking in the fired body, among other advantages.Type: GrantFiled: September 30, 1999Date of Patent: March 27, 2001Assignee: Corning IncorporatedInventors: Douglas M. Beall, Devi Chalasani, Gregory Albert Merkel, Y. Lisa Peng
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Patent number: 6197252Abstract: The invention relates to a method of removing water-insoluble binder from a porous article formed from pressed particulate material, such as tantalum powder. The invention provides a method capable of removing substantially all of the binder from the article for high purity applications, such as capacitor manufacture. The method comprises contacting the article with an aqueous solution of an agent which reacts with said binder to produce a water soluble derivative thereof whereby said binder derivative may be substantially dissolved in said solution. In a particular embodiment, the derivative is produced by hydrolysis of a fatty acid binder.Type: GrantFiled: July 12, 1999Date of Patent: March 6, 2001Assignee: AVX LimitedInventors: Ian H. Bishop, David Masheder
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Patent number: 6190605Abstract: A method for high density long fill compaction of metallic powders uses a precisely temperature controlled mold and a dry sprayed lubricant which has the characteristic of softening on contact with the mold and smearing on the mold wall during compaction, yet on ejection not causing powder adherence.Type: GrantFiled: December 21, 1999Date of Patent: February 20, 2001Assignee: Zenith Sintered Products, Inc.Inventors: Terry M. Cadle, Joel H. Mandel, Paul R. Roskopf
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Patent number: 6187259Abstract: The object of the present invention is to provide rare-earth system sintered magnets such as R—Fe—B system or R—Co system having excellent magnetic properties, unique configuration of a small size, thin wall thickness and intricate geometry. With the method for preparing the present invention, a granulation of alloy powders can be achieved easily, a chemical reaction between rare-earth system and binder substances can be suppressed, so that the residual oxygen and carbon levels in the sintered products can be reduced. Moreover, by this production method, the flowability and lubricant capability during the forming process can be improved. The dimension accuracy and productivity are also enhanced. A certain type of binder is added to rare-earth alloy powders and kneaded into a slurry state. The slurry is then formed into granulated powders by spray-dryer equipment. The thus granulated powders are molded, and sintered through a powder metallurgy technique.Type: GrantFiled: March 19, 1997Date of Patent: February 13, 2001Assignee: Sumitomo Special Metals Co., Ltd.Inventors: Osamu Yamashita, Yoshihisa Kishimoto, Wataru Takahashi, Nobushige Hiraishi, Yoshiyuki Hashimasa, Masakazu Ohkita
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Patent number: 6183688Abstract: A cutting member is manufactured by forming a mixture of cemented carbide and a bearer, and heating the mixture. Then, the heated mixture is injected into a mold for forming a body having a cutting edge in a front surface thereof, a flushing channel extending therethrough, and a rearwardly open blind hold formed centrally in a rear surface thereof. The body is then removed from the mold.Type: GrantFiled: July 7, 1999Date of Patent: February 6, 2001Assignee: Seco Tools ABInventors: Ronny Karlsson, Johnny Bruhn
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Patent number: 6171360Abstract: The present invention relates to a molding method characterized by kneading a binder comprising an agar having an average molecular weight of 30,000 to 150,000 with a metal powder, a ceramic powder, or a mixed powder thereof, injection-molding the thus obtained molding composition into a green body, removing at least the water from the green body, and then sintering the green body to obtain a molded product.Type: GrantFiled: April 7, 1999Date of Patent: January 9, 2001Assignee: Yamaha CorporationInventors: Katsunori Suzuki, Toshiharu Fukushima
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Patent number: 6139600Abstract: An iron-based powder composition is produces in accordance with a method comprising the steps of: adding to iron-based and alloying powders, for a primary mixing, a surface treatment agent, and in addition, for a secondary mixing, a fatty acid amide and at least one lubricant, wherein the lubricant has a melting point higher than that of the fatty acid amide and can be, a thermoplastic resin, a thermoplastic elastomer, and inorganic or organic compounds having a layered crystal structure; heating and stirring up a mixture after the secondary mixing at a temperature above a melting point of the fatty acid amide to melt the fatty acid amide; cooling, while mixing, the mixture subjected to the heating and stirring process so that the alloying powder and a lubricant having a melting point higher than the fatty acid amide adhere to a surface of the iron base powder subjected to the surface treatment by an adhesive force of the melt; and adding at the time of the cooling, for a tertiary mixing, a metallic soap andType: GrantFiled: September 22, 1999Date of Patent: October 31, 2000Assignee: Kawasaki Steel CorporationInventors: Yukiko Ozaki, Satoshi Uenosono, Kuniaki Ogura
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Patent number: 6136265Abstract: A method of forming a coating on metal particles that can be used to produce powder metallurgy articles, including those for electromagnetic and structural applications. The method is generally a solution-blending process that employs a coating solution that contains a solvent and one or more particulate additives, at least one of which is a polymeric binder that is only partially soluble in the solvent. As a result, only a portion of each binder particle is dissolved in the solvent. Notably, the coating solution is free of a discrete adhesion-promoting (tackifier) additive for adhering the polymeric binder to the metal particles. Instead, each binder particle is sufficiently dissolved in the solvent to promote adhesion of the binder particles to the metal particles during mixing, so that each metal particle is encapsulated with a coating containing the polymeric binder. The particles may then be compacted to bind them together with the coating and form a solid article.Type: GrantFiled: August 9, 1999Date of Patent: October 24, 2000Assignee: Delphi Technologies Inc.Inventor: David Earl Gay
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Patent number: 6132486Abstract: A process of forming a multi-phase sintered article of powdered metal comprising: blending a mixture of copper powder, aluminum powder, iron powder, and nickel, each in their free states, with a lubricant, compacting the blended mixture into a die cavity, forming the article, and high temperature sintering the article in a reducing atmosphere comprised of 100% dissociated ammonia so as to produce the multi-phase sintered article of powdered metal; and the multi-phase sintered article of powdered metal formed thereby.Type: GrantFiled: November 9, 1998Date of Patent: October 17, 2000Assignee: Symmco, Inc.Inventor: James N. Dixon
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Patent number: 6126873Abstract: Molding compositions for shaping parts from stainless steel powders are disclosed. The process comprises the steps of forming a mixture comprising stainless steel powder, a gel-forming material having a gel strength, measured at a temperature between 0.degree. C. and about 30.degree. C. and a gel comprising about 1.5 wt % of the gel-forming material and water, of at least about 200 g/cm2, and water, and molding the mixture at a temperature sufficient to produce a self-supporting article comprising the powder and gel. The preferred gel-forming material is an agaroid and the preferred molding process is injection molding.Type: GrantFiled: June 3, 1998Date of Patent: October 3, 2000Assignee: AlliedSignal Inc.Inventors: Michael Sean Zedalis, Rick Duyckinck, Brian Snow, Anthony Fanelli, Joan Virginia Burlew
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Patent number: 6093368Abstract: A base metal repair tape includes a first layer formed braze alloy bonded together with fibrillated polytetrafluoroethylene, a second layer formed from powdered base metal bonded together by fibrillated polytetrafluoroethylene and a third layer comprising a brazing alloy bonded together by fibrillated polytetrafluoroethylene. This is used to repair base metal by placing the first layer on the base metal and brazing the base metal powder so that the brazing alloy melts and diffuses into the base metal powder bonding it to the surface of the article. This permits the braze powder to be bonded to the base metal surface with minimal distance between the base powder particles. The number of alternating layers of base metal and braze alloy can be increased to increase the thickness of the repair. This can also be used to form small intricate parts.Type: GrantFiled: April 3, 1998Date of Patent: July 25, 2000Assignee: C. A. Patents, L.L.C.Inventors: Kevin Rafferty, Bruce Rowe
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Patent number: 6066279Abstract: A method of gelcasting includes the steps of providing a solution of at least hydroxymethylacrylamide (HMAM) and water. At least one inorganic powder is added to the mixture. At least one initiator system is provided to polymerize the HMAM. The initiator polymerizes the HMAM and water, to form a firm hydrogel that contains the inorganic powder. One or more comonomers can be polymerized with the HMAM monomer, to alter the final properties of the gelcast material. Additionally, one or more additives can be included in the polymerization mixture, to alter the properties of the gelcast material.Type: GrantFiled: August 17, 1998Date of Patent: May 23, 2000Assignee: Lockheed Martin Energy Research Corp.Inventors: Claudia A. Walls, Glen H. Kirby, Mark A. Janney, Ogbemi O. Omatete, Stephen D. Nunn, April D. McMillan
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Patent number: 6051184Abstract: A metal powder injection moldable composition which hardly causes debinding deformation is obtained. This composition consists of a metal powder and an organic binder. The components which constitute the organic binder are:a. polyoxymethylene having a Vicat softening temperature A.gtoreq.150.degree. C.,b. polypropylene having a Vicat softening temperature B.gtoreq.130.degree. C.,c. an organic compound whose viscosity at said Vicat softening temperature A (.degree. C.) is not more than 200 mPa.multidot.s, andd. a thermoplastic resin whose Vicat softening temperature is not higher than said B (.degree. C.).Type: GrantFiled: October 15, 1998Date of Patent: April 18, 2000Assignee: Mold Research Co., Ltd.Inventor: Yoshimitsu Kankawa
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Patent number: 6045748Abstract: A method for forming molded articles in any shape from ceramic, glass, or metal powders which comprises: preparing a slurry by dispersing more than one powder selected from a group consisting of ceramic, glass, and metal materials in a dispersing medium using a dispersing agent, and curing by adding a reactive substance that reacts with the dispersing agent to make the dispersibility of the dispersing agent disappear or lower.Type: GrantFiled: July 29, 1998Date of Patent: April 4, 2000Assignee: NGK Insulators, Ltd.Inventor: Shinzo Hayashi
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Patent number: 6042780Abstract: A method for producing high performance components by the consolidation of powdered materials under conditions of hot isostatic pressure. The method uses the inclusion of reactive materials mixed into pressure-transmitting mold materials and into the powder to be consolidated to contribute to in-situ materials modification including purification, chemical transformation, and reinforcement. The method also uses encapsulation of the mold in a sealed container to retain the mold material in position, and to exclude air and contaminants.Type: GrantFiled: December 15, 1998Date of Patent: March 28, 2000Inventor: Xiaodi Huang
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Patent number: 6033623Abstract: A powder metallurgical process of preparing iron aluminide useful as electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 20 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.05% Zr or ZrO.sub.2 stringers extending perpendicular to an exposed surface of the heating element, .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Zr, .ltoreq.1% C, .ltoreq.0.1% B, .ltoreq.30% oxide dispersoid and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1 % rare earth metal, .ltoreq.1% oxygen, and/or .ltoreq.3% Cu.Type: GrantFiled: July 11, 1996Date of Patent: March 7, 2000Assignee: Philip Morris IncorporatedInventors: Seetharama C. Deevi, A. Clifton Lilly, Jr., Vinod K. Sikka, Mohammed R. Hajaligol
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Patent number: 6022509Abstract: An implant component adapted for bone attachment or replacement is molded from a feed stock which contains a soluble major binder, a backbone binder and structural powder material. After the feed stock is injection molded to form a compact or preform, the major binder is removed from the green article, leaving a structure of interconnected porosity or texture, while the backbone binder remains until the component is sintered. Preferably, the amount of the soluble binder is set to increase the porosity, or reduce the stiffness, of the finished component, thus introducing a biocompatible or growth-enhancing level of porosity or stiffness during the molding process. In further or alternative embodiments, the component may be injection molded onto or about a solvent-leachable spacer preform and/or adjacent to another injected or molded portion of the component which serves as a structural body, frame or shell.Type: GrantFiled: September 18, 1998Date of Patent: February 8, 2000Assignee: Johnson & Johnson Professional, Inc.Inventors: Frank D. Matthews, Salvatore Caldarise
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Patent number: 6019937Abstract: A process of forming a sintered article of powder metal comprising blending graphite, Si carbide and lubricant, with pre-alloyed iron base powder; pressing said blended mixture to a shaped article; sintering said article in a reduced atmosphere; forced cooling said sintered article.Type: GrantFiled: November 27, 1998Date of Patent: February 1, 2000Assignee: Stackpole LimitedInventors: Rohith Shivanath, Karol Kucharski, Peter Jones
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Patent number: 6008281Abstract: A powder injection molding composition or feedstock is made of 70% or more by weight of a powdered metal or ceramic and 30% or less by weight of a binder system. The binder system contains a sufficient amount of polypropylene or polyethylene to hold the so-called brown preform of the molded metal or ceramic powder together for the sintering step of the injection molding process and a sufficient amount of partially hydrolyzed cold water soluble polyvinyl alcohol water and plasticizer to facilitate molding of the composition into the so- called green preform of the article to be manufactured. The debinding step of the injection molding process for transforming the green preform into the brown preform consists simply of immersing the green preform in water at ambient temperature to dissolve the polyvinyl alcohol. The binder system is nonhazardous, safe, harmless and fully degradable.Type: GrantFiled: March 9, 1999Date of Patent: December 28, 1999Assignee: Planet Polymer Technologies, Inc.Inventors: Xiaoming Yang, Robert J. Petcavich
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Patent number: 6007764Abstract: The present invention is a method which customizes the penetration depth of a heat-fusible powder used in solid freeform fabrication process such as laser sintering. The penetration depth of the heat-fusible powder is customized by combining opaque and transparent powders at a ratio which ensures that the beam contacts a portion of powder beneath its surface, thereby promoting complete layer sintering as well as adherence to previously sintered layers.Type: GrantFiled: March 27, 1998Date of Patent: December 28, 1999Assignee: United Technologies CorporationInventors: John A. Benda, Aristotle Parasco
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Patent number: 6001150Abstract: Boric acid-containing lubricants are disclosed which consist essentially of boric acid and at least one other powder metallurgy lubricant and provide a synergistic free-flowing composition. There are also provided novel compositions of matter for forming sintered metal components comprising a mixture of sinterable, powdered metal and the said lubricants.Type: GrantFiled: September 25, 1997Date of Patent: December 14, 1999Assignee: H.L. Blachford Ltd./LTEEInventors: James M. McCall, John Blachford, Margaret Cole
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Patent number: 5996385Abstract: A method and apparatus for fabricating high density monolithic metal and oy billets. The process requires preheating precursor materials of metal or alloy billets by means of a combustion synthesis called Self-Propagating High-Temperature Synthesis (SHS). The reaction takes place in an insulated reaction vessel where the precursors, in a powder form, are heated to high temperatures. The precursors are then compacted to high density by means of pressure waves generated by detonation of an explosive. The method is capable of producing high purity tungsten and tungsten-based alloys of greater than 90% theoretical density.Type: GrantFiled: May 20, 1997Date of Patent: December 7, 1999Assignee: The United States of America as represented by the Secretary of the ArmyInventor: Laszlo J. Kecskes
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Patent number: 5997795Abstract: Solid freeform fabrication techniques are used in direct methods to form photonic bandgap structures, and in indirect methods to form molds for photonic bandgap structures. In the direct methods, solid particulate materials are mixed with a binder and, through a computer-controlled process, are built layer by layer to form the structure. In the indirect methods, unfilled polymeric materials are built layer by layer to form a negative mold for the photonic bandgap structure. The cavities within the mold may then be filled with a slurry incorporating solid particulate materials. Subsequent processing may include mold removal, binder removal, densification and secondary infiltration steps to form a photonic bandgap structure having the desired properties.Type: GrantFiled: May 29, 1998Date of Patent: December 7, 1999Assignee: Rutgers, The State UniversityInventors: Stephen C. Danforth, Ahmad Safari, John Ballato, Remco Van Weeren, Amit Bandyopadhyay
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Patent number: 5997603Abstract: A sintered metal mould formed by plastically forming a material consisting of a metal powder or ceramic powder being mixed with a binder consisting of agar powder, and sintering the material.Type: GrantFiled: May 28, 1997Date of Patent: December 7, 1999Assignees: Shimizu Shokuhin Kaisha, Ltd., Apex Co., Ltd.Inventors: Yoshihisa Noro, Junichi Adachi
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Patent number: 5993732Abstract: An R--T--M alloy material, wherein R is at least one rare earth metal including Y, T is Fe or an Fe component partially replaced by Co or Ni, M is B or a B component partially replaced by C as primary components is prepared by heating the alloy at a temperature from room temperature to a specific temperature of less than 500.degree. C. in a non-oxidizing atmosphere and holding it at the given temperature, if necessary; performing hydrogenation by holding the alloy in a hydrogen atmosphere or a mixed gas atmosphere of hydrogen and an inert gas at a specific temperature in the range of 500-1,000.degree. C.; medial annealing the alloy by holding the R--T--M alloy after the hydrogenation step in an inert gas atmosphere at a specific temperature in the range of 500-1,000.degree. C.; and dehydrogenating the alloy by holding the alloy in a vacuum of less than 1 Torr for dehydrogenation, and then cooling the alloy.Type: GrantFiled: July 13, 1998Date of Patent: November 30, 1999Assignee: Mitsubishi Materials CorporationInventors: Ryoji Nakayama, Yoshinari Ishii, Norihito Fukatsu, Koichiro Morimoto
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Patent number: 5993507Abstract: A composition comprising a mixture of coarse and fine iron powder and at least one densification enhancing additive for economically producing metal injection molding components.Type: GrantFiled: December 29, 1997Date of Patent: November 30, 1999Assignee: Remington Arms Co., Inc.Inventors: Louis W. Baum, Maryann Wright
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Patent number: 5989493Abstract: A molding compound consisting of the nickel superalloy Hastelloy X is used to form net-shape or near net-shape articles. The compound, containing atomized Hastelloy X powder having an average particle size less than about 20 .mu.m, is mixed with a liquid carrier, a gel forming binder and processing additives and molded at relatively low pressures in a conventional injection molding machine. A critical air debinding step prior to sintering results in high densification of the article, which has mechanical properties comparable to cast or wrought processed material.Type: GrantFiled: August 28, 1998Date of Patent: November 23, 1999Assignee: AlliedSignal Inc.Inventors: Jerry C. La Salle, Bryan C. Sherman
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Patent number: 5989492Abstract: A process for production of a moulded ceramic and/or metallic body from a ductile material comprising one or more ceramic and/or metallic components, which material is fed into the pre-heated mould cavity (1) of a moulding tool. The moulded tool includes at least two mould parts (4, 5) of which at least one wholly or partly consists of a microporous material with communicating micropores. At least one mould cavity (1) comprising at least one mould surface (2, 3) exhibiting closed micropores is arranged in the microporous mould part (4, 5) or in a microporous section (6) thereof. The microporous mould part (4, 5) or the microporous section (6) thereof is pre-heated by supply of warm fluid, such as a heated gas. Said part (4, 5) or section (6) is after terminated moulding cooled by supply of cold fluid, such as a condensed gas. the invention includes in a further aspect a moulded body produced according to the process.Type: GrantFiled: May 14, 1998Date of Patent: November 23, 1999Assignee: AGA AktiebolagInventor: Owe Larsson
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Patent number: 5985208Abstract: A debinding and sintering method is employed to produce consolidated net shape articles from metal powders including 17-4PH stainless steel alloy by metal injection molding using an agar based aqueous binder. The debinding and sintering step can be combined into one cycle to economically produce components for the consumer and aerospace industries.Type: GrantFiled: August 27, 1998Date of Patent: November 16, 1999Assignee: AlliedSignal Inc.Inventors: Michael Sean Zedalis, Bryan C. Sherman, Jerry C. La Salle
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Patent number: 5976215Abstract: An iron-based powder mixture for powder metallurgy, comprising: an iron-based powder, and from 0.05 to 0.50% by weight of a thermoplastic resin powder which comprises 50% or more by weight of units of at least one monomer selected from the group consisting of acrylic esters, methacrylic esters, and aromatic vinyl compounds, and whose average primary particle size is from 0.03 to 5 .mu.m, whose average agglomeration particle size is from 5 to 50 .mu.m, and whose average molecular weight measured by the specific viscosity of a solution is from 30000 to 5000000.Type: GrantFiled: August 20, 1998Date of Patent: November 2, 1999Assignee: Kawasaki Steel CorporationInventors: Satoshi Uenosono, Yukiko Ozaki, Kuniaki Ogura, Toshio Nagase, Takeo Kobayashi
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Patent number: 5977033Abstract: The present invention relates to particle agglomeration of aluminum powder using a lubricating binder. The resulting powder has improved flowability and can be shaped easily. The aluminum particles are admixed with a lubricant, e.g. polyethylene, and are held together by the lubricant. To agglomerate the aluminum powder, the lubricant is melted and is then solidified to form solid bridges between the aluminum powder particles. The lubricant may be burned out cleanly at temperatures lower than 450.degree. C.Type: GrantFiled: August 5, 1998Date of Patent: November 2, 1999Assignee: National Research Council of CanadaInventors: Louis-Philippe Lefebvre, Yannig Thomas, Sylvain Pelletier
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Patent number: 5977230Abstract: A powder injection molding composition or feedstock is made of 70% or more by weight of a powdered metal or ceramic and 30% or less by weight of a binder system. The binder system contains a sufficient amount of polypropylene or polyethylene to hold the so-called brown preform of the molded metal or ceramic powder together for the sintering step of the injection molding process and a sufficient amount of partially hydrolyzed cold water soluble polyvinyl alcohol, water and plasticizer to facilitate molding of the composition into the so-called green preform of the article to be manufactured. The debinding step of the injection molding process for transforming the green preform into the brown preform consists simply of immersing the green preform in water at ambient temperature to dissolve the polyvinyl alcohol. The binder system is nonhazardous, safe, harmless and fully degradable.Type: GrantFiled: January 13, 1998Date of Patent: November 2, 1999Assignee: Planet Polymer Technologies, Inc.Inventors: Xiaoming Yang, Robert J. Petcavich
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Patent number: 5976457Abstract: The present invention relates to a method for rapid fabrication of molds and mold components. This method involves first the step of producing a digital CAD representation of the mold; using this digital representation to make a set of oversized core and cavity three dimensional models, patterns or replicas, by using solid modeling technologies; placing these models, patterns or replicas respectively into a mold base with die pockets to accept the patterns; powder injection molding fine metal powders around each version of the core and cavity of the part to produce a "green" molded article having the negative or female impression or the original core and cavity patterns; debinding these "green" articles to remove the binder; sintering the debound articles to produce the final tool steel or related alloy molds; and performing secondary operations to fit then into a master mold base as part of a complete molding tool.Type: GrantFiled: August 19, 1997Date of Patent: November 2, 1999Inventors: Herman E. Amaya, Dennis Kent Crounse
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Patent number: 5976455Abstract: A metal cutting insert includes a cemented carbide body having a cutting edge and a hole therein for receiving a fastening screw. The hole includes female screw threads for being screw threaded to the fastening screw. The insert is made by a process involving injection molding and sintering steps.Type: GrantFiled: February 19, 1997Date of Patent: November 2, 1999Assignee: Sandvik ABInventors: Goran Pantzar, Bjorn H.ang.kansson, Stefan Roman, Per-Anders Holmstrom
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Patent number: 5972284Abstract: Solid, homogenous or porous, shaped bodies are formed from different powders such as metals and ceramics by preparation of an aqueous slurry of the powder, which slurry comprises a protein substance which is soluble in water at ambient temperatures and capable of forming an irreversible gel on heating to a temperature not exceeding 90.degree. C. The protein substance, for example albumin, is used in an amount sufficient for the formation of a gel. The slurry is formed into a body of the desired shape by methods such as molding, tapecasting or dropforming and heating to a temperature at least corresponding to the gelling temperature of the protein.Type: GrantFiled: October 3, 1996Date of Patent: October 26, 1999Assignee: SKF Nova ABInventors: Goran Lindsten, Jesper Brandt, Elis Carlstrom, Annika Kristoffersson
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Patent number: 5968428Abstract: Disclosed is a molding method for powder particles, which is excellent in molding performance, and which makes it possible to obtain a preliminary molded product excellent in strength by enhancing mutual bonding between particles in the preliminary molded product. A molding apparatus for powder particles includes an outer frame die having a mold space with a lower punch and an upper punch to be slidably fitted thereto. Slight clearances exist between the outer frame die and the lower and upper punches. A mixture is prepared by mixing a powdery raw material with a liquid additive to cause an exothermic reaction therewith.Type: GrantFiled: June 26, 1997Date of Patent: October 19, 1999Assignee: Honda Giken Kogyo Kabushiki KaishaInventor: Mitsuo Kuwabara
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Patent number: 5966582Abstract: A method for extruding a stiffer powder mixture at lower extrusion pressure involves providing an aqueous mixture of inorganic powder that can be metal, ceramic, glass, glass ceramic, molecular sieve, and/or carbon, fatty acid the main chain of which has at least 12 carbon atoms, thermally gellable cellulose ether binder, and wax that can be paraffin and/or propylene glycol hydroxystearate, wherein the powder is coated with the fatty acid component. If clay is included in the mixture, it is provided as either calcined or hydrous. The mixture is passed through an extruder and through an extrusion die to produce a green extrudate at an extrusion pressure that is equal to or lower than it would be absent the combination of the fatty acid, the cellulose ether binder, and the wax. The mixture in the extruder and the extrudate are stiffer than without this combination.Type: GrantFiled: October 17, 1997Date of Patent: October 12, 1999Assignee: Corning IncorporatedInventors: Devi Chalasani, Ronald E. Johnson
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Patent number: 5963775Abstract: A milled tooth shaped rotary cone drill bit for drilling oil wells and the like manufactured using a powder metallurgy process in which an alloy powder is pressure molded into the desired bit shape, sintered, and precision machined.Type: GrantFiled: September 15, 1997Date of Patent: October 5, 1999Assignee: Smith International, Inc.Inventor: Zhigang Fang