Patents Examined by John Sheehan
  • Patent number: 8562756
    Abstract: The present invention is aimed at providing a method for producing an NdFeB sintered magnet having a higher coercivity and higher squareness of the magnetization curve than ever before. A method for producing an NdFeB sintered magnet according to the present invention includes the steps of forming a layer containing Dy and/or Tb on the surface of an NdFeB sintered magnet base material and then performing a grain boundary diffusion process for diffusing Dy and/or Tb from the aforementioned layer through the crystal grain boundaries of the magnet base material into the magnet base material by heating the magnet base material to a temperature equal to or lower than the sintering temperature thereof, and this method is characterized in that a) the content of a rare earth in a metallic state in the magnet base material is equal to or higher than 12.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: October 22, 2013
    Assignee: Intermetallics Co., Ltd.
    Inventors: Masato Sagawa, Naoki Fujimoto
  • Patent number: 8425695
    Abstract: A rare earth sintered magnet includes a main phase that includes an R2T14B phase of crystal grain where R is one or more rare earth elements including Nd, T is one or more transition metal elements including Fe or Fe and Co, and B is B or B and C; a grain boundary phase in which a content of R is larger than a content of the R2T14B phase; and a grain boundary triple point that is surrounded by three or more main phases. The grain boundary triple point includes an R75 phase containing R of 60 at % to 90 at %, Co, and Cu. The relational expression 0.05?(Co+Cu)/R<0.5 is satisfied. An area where a Co-rich region overlaps with a Cu-rich region in a cross-sectional area of the grain boundary triple point is 60% or more.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: April 23, 2013
    Assignee: TDK Corporation
    Inventors: Takuma Hayakawa, Ryouta Kunieda
  • Patent number: 8414709
    Abstract: The present invention is aimed at providing a method for producing an NdFeB sintered magnet having a higher coercivity and higher squareness of the magnetization curve than ever before. A method for producing an NdFeB sintered magnet according to the present invention includes the steps of forming a layer containing Dy and/or Tb on the surface of an NdFeB sintered magnet base material and then performing a grain boundary diffusion process for diffusing Dy and/or Tb from the aforementioned layer through the crystal grain boundaries of the magnet base material into the magnet base material by heating the magnet base material to a temperature equal to or lower than the sintering temperature thereof, and this method is characterized in that a) the content of a rare earth in a metallic state in the magnet base material is equal to or higher than 12.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: April 9, 2013
    Assignee: Intermetallics Co., Ltd.
    Inventors: Masato Sagawa, Naoki Fujimoto
  • Patent number: 8409368
    Abstract: A nitriding treatment (Step S6) in which an N content of a decarburization-annealed steel strip is increased is performed between start of a decarburization annealing (Step S4) and occurrence of secondary recrystallization in a finish annealing (Step S5). In hot rolling (Step S1), a silicon steel material is held in a temperature range between 1000° C. and 800° C. for 300 seconds or longer, and then finish rolling is performed.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: April 2, 2013
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Yoshiyuki Ushigami, Norikazu Fujii
  • Patent number: 8398879
    Abstract: A powder mixture, which contains a soft magnetic powder and an insulating powder lubricant in an amount of 0.1% by mass or more relative to the soft magnetic powder, is formed by compacting at a compacting pressure of 800 MPa or less, thereby obtaining a powder compact that has a space factor of the soft magnetic powder of 93% or more. The powder compact can be used as a soft magnetic powdered core. The soft magnetic powdered core has a specific resistance or 10,000 ??cm or more. A powder of a metal soap such as barium stearate or lithium stearate is used as the insulating powder lubricant.
    Type: Grant
    Filed: July 8, 2010
    Date of Patent: March 19, 2013
    Assignee: Hitachi Powdered Metals Co., Ltd.
    Inventors: Kohei Muramatsu, Chio Ishihara, Masaki Yanaka
  • Patent number: 8388766
    Abstract: An anisotropic rare earth sintered magnet has a tetragonal R2Fe14B compound as a major magnetic phase, wherein R is Nd or a mixture of Nd with at least one rare earth element. Grains of the compound phase have two crystallographic axes, c and a-axes aligned. The biaxially aligned magnet exhibits a coercivity Hc of at least 1.6 MA/m.
    Type: Grant
    Filed: October 24, 2011
    Date of Patent: March 5, 2013
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventor: Ken Ohashi
  • Patent number: 8388769
    Abstract: To mold a high-resistance magnet at low temperature, including room temperature, the magnet includes magnetic powders, metallic powders having a lower hardness than the magnetic powders and a high-resistance layer, wherein the magnetic powders occupy a larger volume than the metallic powders. In particular, the high-resistance layer contains a fluorine compound and is placed between the magnetic powder and the metallic powders.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: March 5, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Matahiro Komuro, Yuichi Satsu, Takashi Yasuhara
  • Patent number: 8372217
    Abstract: A magnetic core having an iron-based amorphous alloy that includes: a chemical composition with a formula FeaBbSicCd, where 81.5<a?84, 12<b<17, 1?c<5 and 0.3?d?1.0, numbers being in atomic percent, with incidental impurities, simultaneously having a value of a saturation magnetic induction equal to or exceeding 1.63 tesla, a Curie temperature greater than or equal to 315° C. and less than or equal to 360° C. and a crystallization temperature greater than or equal to 400° C. and less than or equal to 470° C. The core has low core loss and exciting power and is suited for transformers, electrical chokes, power inductors and pulse generation and compression devices.
    Type: Grant
    Filed: December 31, 2009
    Date of Patent: February 12, 2013
    Assignees: Metglas, Inc., Hitachi Metals, Ltd.
    Inventors: Ryusuke Hasegawa, Daichi Azuma
  • Patent number: 8372218
    Abstract: Magnet cores pressed using a powder of nanocrystalline or amorphous particles and a pressing additive should be characterized by minimal iron losses. These particles have first surfaces represented by the original strip surfaces and second surfaces represented by surfaces produced in a pulverization process, the overwhelming majority of these second particle surfaces being smooth cut or fracture surfaces without any plastic deformation, the proportion T of areas of plastic deformation of the second particle surfaces being 0?T?0.5.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: February 12, 2013
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventors: Dieter Nuetzel, Markus Brunner
  • Patent number: 8366836
    Abstract: A silicon steel material is heated in a predetermined temperature range according to contents of B, N, Mn, S, and Se (step S1), and is subjected to hot rolling (step S2). Further, a finish temperature Tf of finish rolling in the hot rolling is performed in a predetermined temperature range according to the content of B. Through these treatments, a certain amount of BN is made to precipitate compositely on MnS and/or MnSe.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: February 5, 2013
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiyuki Ushigami, Norikazu Fujii
  • Patent number: 8366837
    Abstract: The invention can provide a dust core that can counteract a large electric current, achieve an increase in frequency and miniaturization, and achieve an improvement in voltage resistance, and a magnetic element using the same. The dust core of the invention is a dust core including metallic magnetic powder, an inorganic insulating material, and a thermosetting resin, in which the metallic magnetic powder has a Vickers hardness (Hv) in a range of 230?Hv?1000, the inorganic insulating material has a compressive strength of 10000 kg/cm2 or lower and is in a mechanical collapse state, and the inorganic insulating material in a mechanical collapse state and the thermosetting resin are interposed between the metallic magnetic powder particles.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: February 5, 2013
    Assignee: Panasonic Corporation
    Inventors: Yuya Wakabayashi, Takeshi Takahashi, Nobuya Matsutani
  • Patent number: 8361242
    Abstract: A powder consists essentially by weight, of 28.00?R?32.00%, where R is at least one rare earth element including Y and the sum of Dy+Tb>0.5, 0.50?B?2.00%, 0.50?Co?3.50%, 0.050?M?0.5%, where M is one or more of the elements Ga, Cu and Al, 0.25 wt %<O?0.5%, 0.15% or less of C, balance Fe.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: January 29, 2013
    Assignee: Vacuumschmeize GmbH & Co. KG
    Inventors: Rolf Blank, Matthias Katter, Werner Rodewald, Boris Wall
  • Patent number: 8358040
    Abstract: A permanent magnet type electric rotating machine having a high resistance permanent magnet used for the electric rotating machine, the permanent magnet containing a magnetic powder and a fluorine compound, in which the current waveform is controlled for reducing the loss to satisfy a relation: A<C<B and restrict the 7th higher-harmonic component to 20% or less where A is the content for the 5th higher harmonic component, B is the content for the 7th higher harmonic component, and C is the content for the 11th higher harmonic component, assuming the total of contents for the fundamental components of a current supplied to the findings being 100%.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: January 22, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Matahiro Komuro, Yuichi Satsu, Haruo Koharagi, Yuji Enomoto
  • Patent number: 8357222
    Abstract: A metal magnetic powder for a magnetic recording medium is provided whose particles have a metal magnetic phase, composed mainly of Fe or Fe plus Co, and an oxide layer, wherein the average major axis length of the powder particles is 10-50 nm, the average particle volume including the oxide layer is 5,000 nm3 or less, the atomic ratio (R+Al+Si)/(Fe+Co) calculated using the content values (at. %) of the elements contained in the powder particles is 20% or less, where R is rare earth element (Y being treated as a rare earth element). The metal magnetic powder is obtained by using a complexing agent and a reducing agent to elute nonmagnetic constituents after firing. The metal magnetic powder exhibits a large saturation magnetization as for its particle volume while maintaining weatherability comparable to the conventional level and is suitable for a coated-type magnetic recording medium.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: January 22, 2013
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Takayuki Yoshida, Masatoshi Nakayama, Ryota Igarashi
  • Patent number: 8337637
    Abstract: A method for ordering a disordered alloy includes: simultaneously ion bombarding and annealing a disordered alloy to transform the disordered alloy from a disordered crystalline state to an ordered crystalline state. A method for making a perpendicular magnetic recording medium which includes an ordered alloy layer is also disclosed.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: December 25, 2012
    Assignee: National Taiwan University
    Inventors: Fu-Te Yuan, An-Cheng Sun, Jen-Hwa Hsu, Ching-Ray Chang
  • Patent number: 8337638
    Abstract: A powder for a dust core comprising a silicon-containing layer formed within a depth of less than 0.15 D from the surface of the surface layer of a soft magnetic metal powder having a particle diameter D and a method for producing the same are provided.
    Type: Grant
    Filed: April 17, 2009
    Date of Patent: December 25, 2012
    Assignees: Toyota Jidosha Kabushiki Kaisha, Fine Sinter Co., Ltd
    Inventors: Yusuke Oishi, Eisuke Hoshina, Toshiya Yamaguchi, Kazuhiro Kawashima
  • Patent number: 8333853
    Abstract: Aluminum alloy having an improved combination of properties are provided. In one aspect, a method for producing the alloy includes preparing an aluminum alloy for artificial aging and artificially aging the alloy. In one embodiment, the artificially aging step includes aging the aluminum alloy at a temperature of at least about 250° F., and final aging the aluminum alloy at a temperature of not greater than about 225° F. and for at least about 20 hours. These aluminum alloys realize an improved combination of properties, including improved strength with at least equivalent fatigue crack growth resistance.
    Type: Grant
    Filed: January 16, 2009
    Date of Patent: December 18, 2012
    Assignee: Alcoa Inc.
    Inventors: Cindie Giummarra, Roberto J. Rioja, Gary H. Bray, Paul E. Magnusen
  • Patent number: 8333846
    Abstract: A manufacturing method of oriented Si steel with high electric-magnetic property comprises the following steps: smelting steel in converter or electric furnace; refining molten steel in two stages; continuous casting to obtain slab; hot rolling; first cold rolling; decarburizing annealing; secondary cold rolling; applying an annealing separator based on MgO and annealing at high temperature; applying an insulating coating and leveling tension annealing. The slab comprises (in wt %): C 0.020-0.050%, Si 2.6-3.6%, S 0.015-0.025%, Als 0.008-0.028%, N 0.005-0.020%, Mn 0.15-0.5%, Cu 0.3-1.2%, balance Fe and inevitable impurities, in which 10?Mn/S?20 and Cu/Mn?2. The method could produce oriented Si steel with high magnetic induction intensity and low iron loss at low cost.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: December 18, 2012
    Assignee: Baoshan Iron & Steel Co., Ltd.
    Inventors: Guohua Yang, Huande Sun, Yaming Ji, Guobao Li, Hongxu Hei
  • Patent number: 8333848
    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: Grant
    Filed: April 14, 2009
    Date of Patent: December 18, 2012
    Assignee: Nitto Denko Corporation
    Inventors: Izumi Ozeki, Katsuya Kume, Junichi Nakayama, Yuuki Fukuda, Toshinobu Hoshino, Tomokazu Horio
  • Patent number: 8328955
    Abstract: A composite magnetic material is manufactured having magnetic properties that can excellently cope with the decreasing size and increasing electric current of magnetic elements, such as choke coils, and can be used in a high frequency range, a dust core using the composite magnetic material, and a method of manufacturing the same. The dust core includes magnetic metal powder and an insulating material, in which the magnetic metal powder has a Vickers hardness (Hv) of 230 ? Hv? 1000, the insulating material has a compressive strength of 10000 kg/cm2 or lower and is in a mechanical collapsed state, and the insulating material in a mechanical collapsed state is interposed in the magnetic metal powder.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: December 11, 2012
    Assignee: Panasonic Corporation
    Inventors: Yuya Wakabayashi, Takeshi Takahashi, Nobuya Matsutani