Using Organic Binder Or Organometallic Patents (Class 264/612)
  • Patent number: 9281107
    Abstract: There are provided a rare-earth permanent magnet and a manufacturing method thereof capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture is prepared by mixing the magnet powder and a binder made of long-chain hydrocarbon and/or of a polymer or a copolymer consisting of monomers having no oxygen atoms. Next, the mixture is formed into a sheet-like shape so as to obtain a green sheet. After that, the green sheet is held for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so as to remove the binder by causing depolymerization reaction or the like to the binder, which turns into monomer. The green sheet from which the binder has been removed is sintered by raising temperature up to sintering temperature. Thereby a permanent magnet 1 is obtained.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: March 8, 2016
    Assignee: NITTO DENKO CORPORATION
    Inventors: Keisuke Taihaku, Katsuya Kume, Toshiaki Okuno, Izumi Ozeki, Tomohiro Omure, Takashi Ozaki
  • Patent number: 8563620
    Abstract: The process for the synthesis of a silica monolith comprises the following steps: hydrolysis of a silicon alkoxide in order to form a hydrolysis precursor followed by a condensation of said hydrolysis precursor in the presence of an organic solvent, in the presence of water and of a basic catalyst in order to form oligomeric clusters containing several silicon atoms; dispersion of said oligomeric clusters in a solution in order to form a sol; polymerization of the sol in order to obtain a gel via a first heat treatment, at a temperature below the boiling point of the constituents of the sol; drying of the gel via a second heat treatment; conversion of the gel to a xerogel via a third heat treatment; dehydration and densification of the xerogel until the silica monolith is obtained via a fourth heat treatment.
    Type: Grant
    Filed: October 1, 2009
    Date of Patent: October 22, 2013
    Assignees: Universite des Sciences et Technologies de Lille, Centre National de la Recherche Scientifique (CNRS)
    Inventors: Mohamed Bouazaoui, Bruno Capoen, Hicham El-Hamzaoui, Laurent Bigot, Géraud Bouwmans
  • Publication number: 20130141195
    Abstract: There are provided a rare-earth permanent magnet and a manufacturing method thereof capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture is prepared by mixing the magnet powder and a binder made of a fatty acid methyl ester and/or one of or a blend of polymers and copolymers each composed of monomers satisfying a given condition. Next, the mixture is formed into a sheet-like shape to obtain a green sheet. After that, the green sheet is held for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so as to remove the binder by causing depolymerization reaction or the like to the binder, which turns into monomer. The green sheet from which the binder has been removed is sintered by raising temperature up to sintering temperature. Thereby a permanent magnet 1 is obtained.
    Type: Application
    Filed: March 15, 2012
    Publication date: June 6, 2013
    Applicant: NITTO DENKO CORPORATION
    Inventors: Keisuke Taihaku, Katsuya Kume, Izumi Ozeki, Toshiaki Okuno, Tomohiro Omure, Takashi Ozaki
  • Publication number: 20130015394
    Abstract: A ferromagnetic powder composition including soft magnetic iron-based core particles, wherein the surface of the core particles is provided with at least one phosphorus-based inorganic insulating layer and then at least partially covered with metal-organic compound(s), wherein the total amount of metal-organic compound(s) is between 0.005 and 0.05% by weight of the powder composition, and wherein the powder composition further includes a lubricant. Further, a process for producing the composition and a method for the manufacturing of soft magnetic composite components prepared from the composition, as well as the obtained component.
    Type: Application
    Filed: February 9, 2011
    Publication date: January 17, 2013
    Applicant: HÖGANÄS AB
    Inventors: Björn Skårman, Zhou Ye
  • Publication number: 20120248913
    Abstract: A ferrite sintered magnet has a surface roughness Rz of 3.5 ?m or less. A method for producing a ferrite sintered magnet includes: mixing magnetic powders with at least a binder resin to obtain a magnetic powder mixture; injection molding the magnetic powder mixture inside of a mold having a surface roughness of a surface in contact with the magnetic powder mixture of 2.0 ?m or less with a magnetic field applied to the mold, to obtain a molded body; and sintering the molded body.
    Type: Application
    Filed: March 27, 2012
    Publication date: October 4, 2012
    Applicant: TDK CORPORATION
    Inventors: Hideyuki UMEZAWA, Yoshihiko MINACHI, Osanori MIZONOUE
  • Publication number: 20120229245
    Abstract: Provided is a soft magnetic powder used for obtaining a dust core having a low hysteresis loss, in particular, in a high temperature range. A soft magnetic powder includes an aggregate of composite magnetic particles, each including a soft magnetic particle containing Fe, Si, and Al, and an insulating coating film disposed on the surface thereof, and satisfies the expressions (1) and (2) below: Expression (1) . . . 27?2.5a+b?29 and Expression (2) . . . 6?b?9, where a represents the Si content (mass %) and b represents the Al content (mass %). The soft magnetic powder is capable of reducing the hysteresis loss, in a high-temperature environment, of a dust core obtained using the soft magnetic powder.
    Type: Application
    Filed: May 17, 2011
    Publication date: September 13, 2012
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD
    Inventors: Asako Watanabe, Toru Maeda
  • Publication number: 20120187611
    Abstract: A metal powder composition including: an iron or iron-based powder composition, and a lubricating combination including a substance A, a substance B, and a substance C; wherein: substance A is a polyolefin, substance B is chosen from a group of saturated and unsaturated fatty acid amides, saturated and unsaturated fatty acid bisamides, saturated fatty alcohols and fatty acid glycerols, and substance C is an amide oligomer having a molecular weight between 500 g/mol and 30 000 g/mol; and wherein the amounts of respective substances A, B and C in weight percent of the iron or iron-based powder composition are: 0.05?A+B<0.4 wt %, C?0.3 wt %, A+B+C?2.0 wt %, and the relation between substances A and B is: B/A>0.5. Also, a method of producing a metal powder composition and a method for producing a green component.
    Type: Application
    Filed: September 1, 2010
    Publication date: July 26, 2012
    Applicant: HOGANAS AB (PUBL)
    Inventors: Mats Larsson, Karin Olsson, Hilmar Vidarsson
  • Publication number: 20120187612
    Abstract: There are provided a permanent magnet and a manufacturing method thereof capable of densely sintering the entirety of the magnet without making a gap between a main phase and a grain boundary phase in the sintered magnet. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)X (M represents Dy or Tb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, X represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.
    Type: Application
    Filed: March 28, 2011
    Publication date: July 26, 2012
    Applicant: Nitto Denko Corporation
    Inventors: Izumi Ozeki, Katsuya Kume, Keisuke Hirano, Tomohiro Omure, Keisuke Taihaku, Toshinobu Hoshino, Takashi Ozaki
  • Publication number: 20110267160
    Abstract: The present invention relates to a permanent magnet manufactured by steps of: pulverizing a magnet raw material into fine particles having a grain size of 3 ?m or less; mixing the pulverized magnet raw material with a rust preventive oil in which a high-melting metal element-containing organic compound or a precursor of a high-melting ceramic is dissolved, thereby preparing a slurry; compression molding the slurry to form a molded body; and sintering the molded body.
    Type: Application
    Filed: April 14, 2009
    Publication date: November 3, 2011
    Applicant: NITTO DENKO CORPORATION
    Inventors: Izumi Ozeki, Katsuya Kume, Junichi Nakayama, Yuuki Fukuda, Toshinobu Hoshino, Tomokazu Horio
  • Publication number: 20110121498
    Abstract: The present invention relates to a method for producing a rare earth sintered magnet including the steps of: molding a mixture of magnetic powder containing a rare earth compound and oil-extended rubber containing oil and rubber to produce a molded body; removing the oil-extended rubber from the molded body; and calcining the molded body from which the oil-extended rubber is removed to produce a rare earth sintered magnet 10.
    Type: Application
    Filed: November 22, 2010
    Publication date: May 26, 2011
    Applicant: TDK Corporation
    Inventors: Shuichiro IRIE, Raitaro Masaoka, Toshiya Hozumi, Tetsuya Chiba
  • Patent number: 7927501
    Abstract: A magnet comprising magnetic powder containing at least one rare earth metal element, and an oxide binder for binding the magnetic powder, wherein an inter-face distance of the binder determined by diffraction analysis is 0.25 to 2.94 nm. The disclosure also discloses a method of manufacturing a magnet comprising; compacting magnetic powder containing at least one rare earth element under pressure in a mold; impregnating the compacted magnetic powder molding with a precursor solution of an oxide material; and heat-treating the compacted magnetic molding impregnated with the precursor thereby to impart an inter-face distance determined by diffraction analysis to the binder in the compacted molding. The distance is 0.25 to 2.94 nm.
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: April 19, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Matahiro Komuro, Yuichi Satsu, Takao Imagawa, Hiroyuki Suzuki
  • Publication number: 20110043311
    Abstract: The present invention relates to a permanent magnet manufactured by steps of: pulverizing a magnet raw material; mixing the pulverized magnet raw material with a rust preventive oil in which a Dy compound or a Tb compound is dissolved, thereby preparing a slurry; compression molding the slurry to form a molded body; and sintering the molded body.
    Type: Application
    Filed: April 14, 2009
    Publication date: February 24, 2011
    Applicant: NITTO DENKO CORPORATION
    Inventors: Izumi Ozeki, Katsuya Kume, Junichi Nakayama, Yuuki Fukuda, Toshinobu Hoshino, Tomokazu Horio
  • Publication number: 20110037548
    Abstract: The present invention relates to a permanent magnet manufactured by steps of: wet-pulverizing a high-melting metal element-containing organic compound or a precursor of a high-melting ceramic in a solvent together with a magnet raw material to pulverize the magnet raw material into fine particles having a grain size of 3 ?m or less and to coat a surface of the pulverized magnet raw material with the high-melting metal element-containing organic compound or the precursor of the high-melting ceramic; adding a resin binder to the magnet raw material coated with the high-melting metal element-containing organic compound or the precursor of the high-melting ceramic; producing a slurry by kneading the magnet raw material and the resin binder; molding the slurry into a sheet form to prepare a green sheet; and sintering the green sheet.
    Type: Application
    Filed: April 14, 2009
    Publication date: February 17, 2011
    Applicant: NITTO DENKO CORPORATION
    Inventors: Izumi Ozeki, Katsuya Kume, Junichi Nakayama, Yuuki Fukuda, Toshinobu Hoshino, Tomokazu Horio
  • Publication number: 20110018664
    Abstract: The present invention relates to a permanent magnet obtained by wet-mixing a Dy compound or a Tb compound with a magnet raw material to coat a surface of the magnet raw material with the Dy compound or the Tb compound, and sintering a green sheet obtained by mixing the resulting magnet raw material with a resin binder and molding the resulting mixture. Since the present invention has the above-mentioned constitution, it becomes possible to sufficiently improve coercive force by Dy or Tb while decreasing the amount of Dy or Tb used. Further, it can be prevented that Dy or Tb is solid-solutionized in magnet particles to decrease residual magnetization.
    Type: Application
    Filed: March 17, 2009
    Publication date: January 27, 2011
    Applicant: NITTO DENKO CORPORATION
    Inventors: Izumi Ozeki, Katsuya Kume, Junichi Nakayama, Yuuki Fukuda, Toshinobu Hoshino, Tomokazu Horio
  • Publication number: 20110012700
    Abstract: The present invention relates to a permanent magnet obtained by sintering a green sheet which is produced by mixing a magnet raw material with a resin binder and molding the resulting mixture, and a method for producing the same. Since the present invention has such a constitution, the contraction due to sintering becomes uniform, whereby the deformations such as warpage and depressions do not occur after sintering. Further, it is unnecessary to perform the conventional correcting processing after sintering, which can simplify the production steps, because the pressure unevenness at the time of pressing disappears. Therefore, it becomes possible to mold the permanent magnet with a high degree of dimension accuracy. Furthermore, even when the permanent magnet is reduced in film thickness, the magnetic characteristics are not deteriorated by the processing-deteriorated layer on the surface.
    Type: Application
    Filed: March 17, 2009
    Publication date: January 20, 2011
    Applicants: NTTO DENKO CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Izumi Ozeki, Katsuya Kume, Junichi Nakayama, Yuuki Fukuda, Toshinobu Hoshino, Tomokazu Horio, Kenji Nakamura
  • Publication number: 20100224822
    Abstract: The present invention relates to ferromagnetic powders with an electrically insulating layer on iron particles intended for the manufacture of components having improved soft magnetic properties at low and medium frequencies. The invention comprises an iron powder coated with a dielectric insulating layer comprising boron bearing compounds to form an insulated ferromagnetic powder. The present invention also relates to a method of making these insulated ferromagnetic powders. The present invention further relates to a method of synthesizing a product made from insulated ferromagnetic powders via a post-heat treatment at a moderate temperature (300° C. to 700° C.), to form a glass-like coating which acts as an electrical insulator. A preferred embodiment of the present invention is obtained when small amounts of alkali bearing compounds are added to the precursors to modify the coating chemistry and significantly increase the electrical resistivity after heat treatment.
    Type: Application
    Filed: March 5, 2009
    Publication date: September 9, 2010
    Applicant: Quebec Metal Powders, Ltd.
    Inventors: Guillem Vachon, Claude Gelinas
  • Patent number: 7712213
    Abstract: A method is provided for making an encapsulated stack of circuit boards. The method includes assembling the stack of circuit boards from a plurality of circuit boards, the circuit boards being spaced apart from each other; inserting the stack into an internal volume of a shell, the shell having a first end and a second end opposite the first end, an input orifice adjacent the first end, and an output orifice adjacent the second end and on a side opposite the input orifice; positioning the shell such that the input orifice is at a lowest point of any part of the internal volume of the shell, and such that the output orifice is at a highest point of any part of the internal volume of the shell; angling the shell relative to horizontal; and injecting an encapsulating compound into the input orifice to fill the internal volume of the shell with the encapsulating compound.
    Type: Grant
    Filed: December 1, 2006
    Date of Patent: May 11, 2010
    Assignee: AAI Corporation
    Inventor: Michael J. Karmazyn
  • Publication number: 20090302512
    Abstract: The invention relates to a soft-magnetic material comprising a micro fraction composed of particles of a soft-magnetic material having a particle size in the range from 1 to 100 ?m and a nano fraction composed of particles of a soft-magnetic material having a particle size in the range from 100 to 200 nm, where the proportion of the nano fraction based on the total mass of micro fraction and nano fraction is from 5 to 70% by mass and the particles of the micro fraction and the particles of the nano fraction optionally consist of the same material, and also a process for producing an article composed of the soft-magnetic material.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Tridelta Weichferrite GmbH
    Inventors: Silvio Gablenz, Marko Kloucek
  • Publication number: 20080248245
    Abstract: A soft magnetic material includes a plurality of composite magnetic particles. Each of the plurality of composite magnetic particles has a metal magnetic particle including iron, a lower film surrounding the surface of the metal magnetic particle and including a nonferrous metal, and an insulating upper film surrounding the surface of the lower film and including an inorganic compound. The inorganic compound contains at least one element of oxygen and carbon. The nonferrous metal has an affinity with at least one of oxygen and carbon that is larger than such affinity of iron. The nonferrous metal has a diffusion coefficient with respect to at least one of oxygen and carbon that is smaller than such diffusion coefficient of iron. Thus, a soft magnetic material that provides desirable magnetic properties, a method of manufacturing a soft magnetic material, a dust core, and a method of manufacturing a dust core are provided.
    Type: Application
    Filed: July 20, 2006
    Publication date: October 9, 2008
    Inventors: Toru Maeda, Haruhisa Toyoda, Naoto Igarashi, Kazuhiro Hirose, Seiji Ishitani, Hiroko Morii, Kazuyuki Hayashi
  • Patent number: 7425284
    Abstract: The purpose of the invention is a process for making a solid part designed to form all or part of an anode for the production of aluminium by fused bath electrolysis, containing a cermet formed from at least one metallic oxide such as a mixed oxide with spinel structure, and at least one metallic phase, in which a mixed oxide is used containing a metal R in the form of a cation in its chemical structure, the said metal R being fully or partly reducible by a reduction operation during the manufacturing process, so as to form all or part of the said metallic phase. This process can provide a cermet with a uniform distribution of fine metallic particles.
    Type: Grant
    Filed: October 5, 2004
    Date of Patent: September 16, 2008
    Assignee: Aluminum Pechiney
    Inventors: Philippe Tailhades, Abel Rousset, Armand Gabriel, Véronique Laurent, Valérie Baco-Carles, Airy-Pierre Lamaze
  • Patent number: 7326360
    Abstract: Magnetostrictive material based on cobalt ferrite is described. The cobalt ferrite is substituted with transition metals (such manganese (Mn), chromium (Cr), zinc (Zn) and copper (Cu) or mixtures thereof) by substituting the transition metals for iron or cobalt to form substituted cobalt ferrite that provides mechanical properties that make the substituted cobalt ferrite material effective for use as sensors and actuators. The substitution of transition metals lowers the Curie temperature of the material (as compared to cobalt ferrite) while maintaining a suitable magnetostriction for stress sensing applications.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: February 5, 2008
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: David C. Jiles, Jason A. Paulsen, John E. Snyder, Chester C. H. Lo, Andrew P. Ring, Keith A. Bormann
  • Patent number: 7255807
    Abstract: A ferrite magnetic powder for bond magnet that experiences only small decrease in coercivity when molded into a bond magnet is provided, which is a ferrite magnetic powder that includes an alkaline-earth metal constituent and exhibits a decrease in coercivity of not greater than 600 Oe when subjected to a prescribed molding test. The magnetic powder can be obtained by mixing a fine ferrite powder of an average particle diameter of greater than 0.50 to 1.0 ?m and a coarse ferrite powder of an average particle diameter of greater than 2.50 to 5.0 ?m at ratio to incorporate the fine powder at a content ratio of 15-40 wt %.
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: August 14, 2007
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Masayasu Senda, Shinichi Suenaga, Keisuke Ayabe, Toshiyuki Sakai
  • Patent number: 7195717
    Abstract: A ferrite core comprising a sintered oxide containing at least 48.6 to 53.9 mol % of Fe on Fe2O3 basis, 12.3 to 35.2 mol % of Ni on NiO basis and 16.4 to 37.0 mol % of Zn on ZnO basis as metal elements, and contains a crystal phase comprising two or more kinds of solid solutions selected from NiFe2O4, ZnFe2O4 and FeFe2O4, wherein full width at half maximum of a diffraction peak, of crystal phase of which diffraction angle 2? is in a range from 34.6 to 36.4° as measured by X-ray diffraction analysis using Cu—K? beam, is 0.4° or less.
    Type: Grant
    Filed: July 27, 2004
    Date of Patent: March 27, 2007
    Assignee: Kyocera Corporation
    Inventors: Chisato Ishida, Masayuki Moriyama, Hidehiro Takenoshita
  • Patent number: 6571858
    Abstract: A method of manufacturing a preform for compounding use which, is to be impregnated with a molten metal to be compounded with a matrix material, is provided. The method includes the step of mixing short fibers, ceramic particles and a binder material together to make a mixture. The average of lengths of the short fibers is 100 to 200 &mgr;m while the volumetric percentage of the short fibers is 1 to 7%. The content of the binder material in the mixture is 0.3 to 5.0 mass %. The method includes also the steps of forming the mixture so as to have a predetermined shape, and sintering the mixture at a temperature of 1000 to 1150° C. to form the preform. Thus, it is restrained that the preform is deformed or an un-reinforced region is formed in the compounded portion.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: June 3, 2003
    Assignee: Mazda Motor Corporation
    Inventor: Makoto Fujita
  • Patent number: 6562458
    Abstract: The invention concerns a process for the preparation of an insulated soft magnetic powder comprising the steps of mixing particles of a soft magnetic iron base powder with an acidic, aqueous insulating-layer forming solution, in which MgO has been dissolved; and drying the obtained mixture to obtain an electrically insulating Mg containing layer on the particle surfaces. The invention also concerns the powder per se as well as compressed soft magnetic powder cores prepared from the powder.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: May 13, 2003
    Assignee: Höganäs AB
    Inventors: Cecilia Elgelid, Anne Larsson-Westberg, Lars-&angst;ke Larsson
  • Publication number: 20030062660
    Abstract: A method for forming composite parts of two or more dissimilar materials by injection molding. Two or more different metallic- or ceramic-based powder materials are used to form two or more different feedstocks, which are each melted and injected under heat and pressure into mold cavities and allowed to solidify to form a composite green compact. In an example of the present invention, two or more powder materials are each mixed with a binder system and granulated to form feedstocks, the feedstocks are melted and concurrently or sequentially injected into a mold and allowed to solidify, and the solidified composite green compact is then subjected to binder removal and sintering processes.
    Type: Application
    Filed: October 3, 2001
    Publication date: April 3, 2003
    Inventors: Bradley D. Beard, Matthew W. Crump, Tom L. Stuart
  • Patent number: 6517744
    Abstract: A heat-conductive sheet comprising a cured or semi-cured binder wherein a carbon fiber is orientated in the direction of the thickness of the heat-conductive sheet. This heat-conductive sheet exhibits a high anisotropic heat conductivity along the direction of the thickness thereof to thereby enable efficiently releasing heat from a heating element such as a semiconductor element or semiconductor package. Moreover, the heat-conductive sheet is excellent in not only heat resistance, durability and mechanical strength but also adherence to the heating element.
    Type: Grant
    Filed: November 14, 2000
    Date of Patent: February 11, 2003
    Assignee: JSR Corporation
    Inventors: Takeo Hara, Shin-ichiro Iwanaga, Hozumi Sato, Ryoji Setaka
  • Patent number: 6488885
    Abstract: A health support device having a lamination of a semiconductor film on a surface of a partially-reduced sintered material of titanium oxide. The semiconductor film is preferably a p-type semiconductor film of silicon or germanium. The partially-reduced sintered material is preferably represented by TiO2−x, where 0<×<0.5. The thickness of the semiconductor film is preferably from 1 nm to 500 nm. In production, a mixture of a titanium oxide powder and a binder is press-molded, and the molded material is sintered at a temperature of from 500° C. to 1100° C. in a vacuum, inert or reducing atmosphere. A p-type semiconductor film is formed on a surface of the resulting partially-reduced sintered material of titanium oxide.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: December 3, 2002
    Assignee: Furukawa Co., Ltd.
    Inventors: Saburo Ishiguro, Yoshitsugu Fujita, Tetsuhiro Iwata
  • Patent number: 6423264
    Abstract: A method of a manufacturing rotating electromagnetic component to have both soft and hard (permanent) magnet regions, in which powder technologies are used to net-shape mold the component. A soft magnet powder material and an insert or powder of a permanent magnet material are compacted to form a rotating electromagnetic body containing soft and hard magnet regions. A partial sintering operation is then performed on the body at a temperature of 1600° F. (about 870° C.) or less, preferably about 1400° F. to 1500° F. (about 760° C. and 830° C.), and most preferably at 1500° F. to at least partially fuse the soft magnet powder materials with the permanent magnet material. The soft powder component of the resulting electromagnetic body is sufficiently fused to exhibit mechanical properties comparable to a fully sintered body (i.e., sintered at 2050° F. (about 1120° C.) or more), but without degrading the magnetic properties of the hard magnet region.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: July 23, 2002
    Assignee: Delphi Technologies, Inc.
    Inventor: David Earl Gay
  • Publication number: 20020084439
    Abstract: An extrudable magnet composition includes composite particles including thermoplastic resin and magnetic material, and a surface additive selected from silicon dioxide particles and ferrite particles, wherein the surface additive is applied to a surface of the composite particles.
    Type: Application
    Filed: December 28, 2000
    Publication date: July 4, 2002
    Applicant: Xerox Corporation
    Inventors: Steven C. Hart, Lois A. Eckstrom
  • Patent number: 6403017
    Abstract: A process for producing Mn—Zn ferrite having large electrical resistance and being durable to the use in high frequency region exceeding 1 MHz easily and at low cost is disclosed. The process comprises pressing a mixed powder comprising a composition of 44.0 to 50.0 mol % of Fe2O3, 4.0 to 26.5 mol % of ZnO, 0.1 to 8.0 mol % of at least one member selected from the group consisting of TiO2 and SnO2, and the remainder being MnO, and if desired 0.1 to 16.0 mol % of CuO, sintering the resulting green compact in the air or an atmosphere containing an appropriate amount of oxygen, and then cooling the green compact, thereby securing the estimated high initial permeability even in a high frequency region of 1 MHz or more.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: June 11, 2002
    Assignee: Minebea Co., Ltd.
    Inventors: Osamu Kobayashi, Osamu Yamada, Koji Honda, Shunji Kawasaki
  • Patent number: 6387293
    Abstract: A composition for a rare earth bonded magnet, the rare earth bonded magnet and the method for manufacturing the rare earth bonded magnet are provided that produce little decline in mechanical strength caused by the addition of a lubricant and have excellent molding properties. The rare earth bonded magnet of the present invention is manufactured from the composition for the magnet that contains rare earth magnetic powder, binding resin containing thermoplastic resin, and fluorine-based resin powder, by compaction molding, extrusion molding or injection molding. The fluorine-based resin powder has the properties of improving mainly lubrication between a molding and a metallic mold. The content of the fluorine-based resin powder in the composition for the rare earth bonded magnet is preferably less than 20 vol % relative to the thermoplastic resin, and the particle diameter of the fluorine-based resin powder is preferably 2-30 &mgr;m.
    Type: Grant
    Filed: March 16, 2000
    Date of Patent: May 14, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Koji Akioka, Yoshiki Nakamura, Ken Ikuma
  • Patent number: 6379579
    Abstract: Provided are a method for preparing an Ni—Cu—Zn ferrite powder having excellent sinterability at a lower temperature, and a method for producing a laminated chip inductor from the above ferrite powder. The method for preparing the ferrite powder is a method for the preparation of a soft magnetic ferrite powder composed of Fe, Ni, Cu and Zn as main components, and comprises the step of allowing an organic additive to be present in a slurry containing a calcined product of a starting powder and water, wherein the organic additive is an organic compound having a hydroxyl group and a carboxyl group or a neutralization salt or lactone thereof, or the organic additive is an organic compound having a hydroxymethylcarbonyl group, an organic compound having an enol type hydroxyl group dissociable as an acid or a salt thereof.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: April 30, 2002
    Assignee: TDK Corporation
    Inventor: Hiroshi Harada
  • Publication number: 20020008336
    Abstract: Provided are an inexpensive Mn—Zn ferrite material having a high resistance, a high permeability, and a low core loss, a manufacturing method thereof, and a deflection yoke core using the material. The ferrite material contains, as main components, 43.0-49.5 mol % of Fe2O3, 33.5-49.0 mol % of MnO, and 8.0-17.0 mol % of ZnO, wherein the ratio of ZnO mol %/Fe2O3 mol % is in a range of 0.35 or less. Preferably, the ferrite material further contains, as sub-components, at least one or more of 0.006-0.12 wt % of CaO, 0.001-0.05 wt % of SiO2, and 0.1-1.0 wt % of Bi2O3. The oxygen concentration of its atmosphere for sintering of the deflection yoke core is specified in a range of 3 to 13%. Preferably, the cooling rate until cooled to 500° C. after the sintering is set in a range of 120° C./hr to 400° C./hr.
    Type: Application
    Filed: July 20, 1999
    Publication date: January 24, 2002
    Inventors: SHUICHI OTOBE, TETUJI AKIYAMA, YASUYUKI MASUDA
  • Patent number: 6296791
    Abstract: A process for producing Mn—Zn ferrite is disclosed, which enables regeneration and reuse of scraps of a sintered product. The process comprises reusing a powder obtained by milling the sintered product of Mn—Zn ferrite, subjecting the powder to a component adjustment so as to have a composition of 44.0 to 50.0 mol % of Fe2O3, 4.0 to 26.5 mol % of ZnO, 0.1 to 8.0 mol % of at least one member selected from the group consisting of TiO2 and SnO2, and the remainder being MnO, and optionally 0.1 to 16.0 mol % of CuO, pressing the resulting mixed powder after the component adjustment, and then sintered a green compact.
    Type: Grant
    Filed: April 3, 2000
    Date of Patent: October 2, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Osamu Kobayashi, Osamu Yamada, Koji Honda, Shunji Kawasaki
  • Publication number: 20010019771
    Abstract: The invention concerns a process for the preparation of an insulated soft magnetic powder comprising the steps of mixing particles of a soft magnetic iron base powder with an acidic, aqueous insulating-layer forming solution, in which MgO has been dissolved; and drying the obtained mixture to obtain an electrically insulating Mg containing layer on the particle surfaces. The invention also concerns the powder per se as well as compressed soft magnetic powder cores prepared from the powder.
    Type: Application
    Filed: January 16, 2001
    Publication date: September 6, 2001
    Inventors: Cecilia Elgelid, Anne Larsson-Westberg, Lars-Ake Larsson
  • Patent number: 6248289
    Abstract: A method for molding relatively complex and large shapes by a co-injection molding process which results in a significantly less expensive and lighter molded product. The process steps include first injection molding a thermoplastic material highly densified with ceramic or stainless steel particulate material to form a shell structure having a homogeneous dispersion of the ceramic or stainless steel material within its matrix and then injecting a significantly less expensive material into the core of the preformed thermoplastic/ceramic or stainless steel structure and thereafter sintering the resulting molded structure. The resultant structure is a hollow shell of highly densified ceramic or stainless steel.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: June 19, 2001
    Assignee: Xerox Corporation
    Inventor: Jay lee Schneider
  • Patent number: 6221270
    Abstract: A process for producing a compound for a rare earth metal resin-bonded magnet includes: a slurry preparation step of mixing materials containing a magnetic alloy powder of a rare earth metal alloy, a resin binder, and an organic solvent into a slurry; and a drying step of spraying and drying the slurry by means of a spray dryer apparatus to produce the compound containing the magnetic alloy powder of the rare earth metal alloy and the resin binder.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: April 24, 2001
    Assignee: Sumitomo Special Metal Co., Ltd.
    Inventors: Katsuyoshi Saito, Yasunari Kaneko, Naoyuki Ishigaki, Shin Mishima, Shinji Otsuki, Yoshihiko Nishino
  • Patent number: 6217820
    Abstract: A method of manufacturing a ferrite sintered body includes the steps of: adding B4C in a ferrite raw material and firing the ferrite raw material, whereby the ferrite sintered body has a high &mgr;i and a high Q, is less irregular in its characteristics, has a high volume resistivity and is capable of preventing deterioration of insulating resistance.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: April 17, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Junji Kurobe, Hideo Ajichi, Takashi Kodama, Takehiro Konoike, Akihiro Nakamura
  • Patent number: 6193903
    Abstract: Ceramic-coated powdered ferromagnetic materials for forming magnetic articles, and which maintain the mechanical and magnetic properties of the articles at high temperatures, such as during annealing to relieve stresses induced during the forming operation. The ceramic coatings are formed by one of several techniques to provide an encapsulating layer on each ferromagnetic particle. The particles are then compacted to form a solid magnetic article, which can be annealed without concern for degrading the ceramic coating.
    Type: Grant
    Filed: May 14, 1999
    Date of Patent: February 27, 2001
    Assignee: Delphi Technologies, Inc.
    Inventors: David Earl Gay, David Allen Score
  • Patent number: 6174453
    Abstract: Disclosed is a method for the preparation of a ferrite beads composition suitable for compression-molding into a compression-molded ferrite body to be subjected to a sintering heat treatment to give a sintered ferrite member having usefulness as an electromagnetic material. The method comprises the steps of: forming ferrite beads from ferrite particles and an organic binder compound; and uniformly mixing the ferrite beads with a limited amount of a higher fatty acid ester of a hexitan compound such as sorbitan mono- or sesquioleate. The ferrite beads composition of the invention is advantageous not only in respect of the behavior in compression molding such as high density of the compression-molded body, low withdrawal pressure from the metal mold and a decrease in the phenomenon of springback but also in respect of the properties of the ferrite body after sintering.
    Type: Grant
    Filed: September 21, 1999
    Date of Patent: January 16, 2001
    Assignee: TDK Corporation
    Inventor: Hiroshi Harada
  • Patent number: 6113843
    Abstract: The process for the preparation of an oxide magnetic compact of the invention comprises:a step of preparing a mixed material which comprises 44 to 50 mole % of iron calculated as Fe.sub.2 O.sub.3, 0.1 to 8 mole % of manganese calculated as Mn.sub.2 O.sub.3, with the sum of iron and manganese being 50 to 54 mole % calculated as Fe.sub.2 O.sub.3 and Mn.sub.2 O.sub.3, 20 to 38 mole % of magnesium calculated as MgO, 17 to 22 mole % of zinc calculated as ZnO and not more than 5 mole % of copper calculated as CuO, anda step of molding the aforesaid mixed material to a predetermined shape and then firing it in an atmosphere of low oxygen concentration of 2.5 to 12% by volume. Therefore, there appears an extremely excellent effect that the oxide magnetic compact having excellent electromagnetic properties can be obtained at low cost.
    Type: Grant
    Filed: March 23, 1999
    Date of Patent: September 5, 2000
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Taku Murase, Kazuhiro Takakura, Jun Sawai, Naoyoshi Sato
  • Patent number: 6086781
    Abstract: The magnetic powder and the sintered magnet of the invention contains a primary phase of a hexagonal ferrite containing A, Co or R wherein A represents Sr, Ba or Ca, and R represents at least one element which may be rare earth elements including Y, and Bi, and have at least two different Curie temperatures, wherein the two different Curie temperatures are present within a range of from 400 to 480.degree. C., and an absolute value of a difference therebetween is 5.degree. C. or more. As both the saturation magnetization and the magnetic anisotropy of the M type ferrite therein are increased, the magnetic powder and the wintered magnet have a high residual magnetic flux density and a high coercive force, which conventional M type ferrite magnets could not have, while having excellent temperature characteristics of coercive force.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: July 11, 2000
    Assignee: TDK Corporation
    Inventors: Hitoshi Taguchi, Kiyoyuki Masuzawa, Yoshihiko Minachi, Kazumasa Iida, Mitsuaki Sasaki, Fumihiko Hirata
  • Patent number: 6063322
    Abstract: A method for producing shaped bodies from hard ferrites, includes (a) providing a powder of hard ferrite material having a fine particle size; (b) adding to the powder a plastifying and bonding agent which comprises (a) at least one of cyclododecane, cyclododecanol, and stearyl alcohol and (b) stearic acid to provide a mixture; (c) shaping the mixture into a blank; (d) heating at a temperature effective to remove the plastifying and bonding agent from the blank; and (e) subsequently heating the blank to a temperature effective to sinter the powder. The method is suitable for the production of magnets, in particular segmental magnets.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: May 16, 2000
    Assignee: Robert Bosch GmbH
    Inventors: Waldemar Draxler, Wilfried Aichele, Uwe Laukant, Horst Boeder
  • Patent number: 5711912
    Abstract: A process for forming a ceramic coated element formed by first encapsulating the element within a sacrificial material and then encapsulating the element and the sacrificial material with an unsintered ceramic material. The resultant combination of materials and elements is then controllably heated to a temperature that burns the sacrificial material prior to the curing of the ceramic material so as to permit the permeation of the burned sacrificial material through the ceramic material. As the ceramic material is sintered it shrinks around the encapsulated element to form the ceramic coated element. In the preferred embodiment of the invention the coated element is a magnet or magnetizable material that is magnetized to a preferred axis of magnetization during the cooling phase of the process.
    Type: Grant
    Filed: June 16, 1996
    Date of Patent: January 27, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Edward Paul Furlani, Syamal K. Ghosh