With Special Compositions Patents (Class 148/122)
  • Patent number: 11270841
    Abstract: This disclosure is directed to sintered bodies comprising grains and a grain boundary composition, wherein: (a) the grains comprise a composition substantially represented by a formula G2M14B, where G is Nd, Dy, Pr, Tb, or a combination thereof, and M is Co, Fe, Ni, or a combination thereof, wherein the grains are optionally doped with one or more rare earth elements; and (b) the grain boundary composition is an alloy composition substantially represented by the formula: Nd8.5-12.5Dy35-45Co32-41Cu3-6.5Fe1.5-5, wherein the subscript values are atom percent relative to the total composition of the alloy composition. Corresponding populations of particles are also disclosed.
    Type: Grant
    Filed: August 23, 2019
    Date of Patent: March 8, 2022
    Assignee: Urban Mining Company
    Inventors: Miha Zakotnik, Walter Del Pozzo
  • Patent number: 11120931
    Abstract: An object of the present invention is to provide an R-T-B based permanent magnet having a low coercive force and a low magnetizing field, and having a high residual magnetic flux density and a high minor curve flatness even in the low magnetizing field. Provided is an R-T-B based permanent magnet including a main phase crystal grain including a compound having an R2T14B type tetragonal structure and a grain boundary phase existing between the main phase crystal grains, in which R is at least one rare earth element including scandium and yttrium, T is at least one transition metal element including iron, or at least two transition metal elements including iron and cobalt, an average diameter D50 of the main phase crystal grain is 1.00 ?m or less, and a content of carbon included in the R-T-B based permanent magnet is 3,000 ppm or more.
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: September 14, 2021
    Assignee: TDK CORPORATION
    Inventors: Shota Miyazaki, Keiji Takeda
  • Patent number: 9336932
    Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for creating magnetic material. One of the methods may make a compound that includes at least one of: i) an amount of Nd in a range of [6.1717, 11.8917] (at. %), inclusive, ii) an amount of Pr in a range of [1.5495, 4.821] (at. %), inclusive, or iii) an amount of Dy in a range of [0.2132, 5.3753] (at. %), inclusive, and an amount of Co in a range of [0, 4.0948] (at. %), inclusive, an amount of Cu in a range of [0.0545, 0.2445] (at. %), inclusive, and an amount of Fe in a range of [81.1749, 85.867] (at. %), inclusive.
    Type: Grant
    Filed: June 17, 2015
    Date of Patent: May 10, 2016
    Assignee: Urban Mining Company
    Inventors: Miha Zakotnik, Walter Del Pozzo
  • Patent number: 9144865
    Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for recycling magnetic material. One of the systems includes a gas mixing apparatus for fragmenting and mixing waste magnetic material comprising a plurality of reaction vessels, each of the plurality of reaction vessels comprising an internal liner having a plurality of openings defined therein, each of the internal liners configured to receive magnetic material and facilitate the circulation of gas around the magnetic material through the plurality of openings, and a pump and valve assembly operatively coupled to the plurality of reaction vessels to control the introduction of gas into the plurality of reaction vessels and to control transfer of gas between the plurality of reaction vessels.
    Type: Grant
    Filed: November 17, 2014
    Date of Patent: September 29, 2015
    Inventors: Miha Zakotnik, Peter Afiuny, Scott Dunn, Catalina Oana Tudor
  • Patent number: 9053846
    Abstract: There are provided a permanent magnet and a manufacturing method thereof enabling carbon content contained in magnet particles to be reduced in advance before sintering even when wet milling is employed. Coarsely-milled magnet powder is further milled by a bead mill in a solvent together with an organometallic compound expressed with a structural formula of M?(OR)x (M includes at least one of neodymium, praseodymium, dysprosium and terbium, each being a rare earth element, 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 magnet powder. Thereafter, a compact body of compacted magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius to perform hydrogen calcination process. Thereafter, through sintering process, a permanent magnet 1 is manufactured.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: June 9, 2015
    Assignee: NITTO DENKO CORPORATION
    Inventors: Izumi Ozeki, Katsuya Kume, Keisuke Hirano, Tomohiro Omure, Keisuke Taihaku, Takashi Ozaki
  • Patent number: 8945318
    Abstract: In an R—Fe—B based rare-earth sintered magnet according to the present invention, at a depth of 20 ?m under the surface of its magnet body, crystal grains of an R2Fe14B type compound have an (RL1-xRHx)2Fe14B (where 0.2?x?0.75) layer with a thickness of 1 nm to 2 ?m in their outer periphery. In this case, the light rare-earth element RL is at least one of Nd and Pr, and the heavy rare-earth element RH is at least one element selected from the group consisting of Dy, Ho and Tb.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: February 3, 2015
    Assignee: Hitachi Metals, Ltd.
    Inventors: Koshi Yoshimura, Hideyuki Morimoto, Tomoori Odaka
  • Patent number: 8795449
    Abstract: The present invention relates to a Fe—Ga—Al-based magnetostrictive thin-sheet material and a process for preparation thereof. The raw materials used for production of the thin-sheet material is composed of the components according to the general Formula, Fe100-x-y-zGaxAlyMz, wherein x=10-30, y=1-10, and z=0.1-5, and M is any one, or more elements selected from V, Cr, Zr, Sb, Sn, Ti, SiC.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: August 5, 2014
    Assignee: Beijing Magoriental Materials Technology Co., Ltd.
    Inventors: Xuexu Gao, Jiheng Li, Maocai Zhang, Jie Zhu, Lina Dong
  • Publication number: 20140166159
    Abstract: The invention provides a La(Fe,Si)13-based magnetic refrigeration material prepared from industrial-pure mischmetal as the raw material, wherein the industrial-pure mischmetal is impurity-containing and naturally proportionated La—Ce—Pr—Nd mischmetal or LaCe alloy which, as the intermediate product during rare earth extraction, is extracted from light rare earth ore. The invention further provides the preparation method and use of the material, wherein the preparation method comprises the steps of smelting and annealing industrial-pure mischmetal as the raw material to prepare the La(Fe,Si)13-based magnetic refrigeration material. The presence of impurities in the industrial-pure mischmetal has no impact on the formation of the 1:13 phase, the presence of the first-order phase-transition property and metamagnetic behavior, and thus maintains the giant magnetocaloric effect of the magnetic refrigeration material.
    Type: Application
    Filed: July 13, 2012
    Publication date: June 19, 2014
    Inventors: Ling Chen, Fengxia Hu, Jing Wang, Lifu Bao, Yingying Zhao, Baogen Shen, Jirong Sun, Huayang Gong
  • Patent number: 8557330
    Abstract: A manufacturing method of a soft magnetic material has a step of preparing a metal magnetic particle containing iron as the main component, and a step of forming an insulating film surrounding the surface of the metal magnetic particle. The step of forming the insulating film includes a step of mixing and stirring the metal magnetic particle, aluminum alkoxide, silicon alkoxide, and phosphoric acid.
    Type: Grant
    Filed: March 1, 2012
    Date of Patent: October 15, 2013
    Assignees: Sumitomo Electric Industries, Ltd., Toda Kogyo Corp.
    Inventors: Toru Maeda, Naoto Igarashi, Haruhisa Toyoda, Seiji Ishitani, Hiroko Morii, Kazuyuki Hayashi
  • Patent number: 8421292
    Abstract: A permanent magnet motor includes: a rotor and a stator; and a plurality of permanent magnets placed on either the rotor or the stator. Each permanent magnet is an R—Fe—B based rare-earth sintered magnet including a light rare-earth element RL (at least one of Nd and Pr) as a major rare-earth element R, and partially includes a high coercivity portion in which a heavy rare-earth element RH (at least one element selected from the group consisting of Dy, Ho and Tb) is diffused in a relatively higher concentration than in the other portion.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: April 16, 2013
    Assignee: Hitachi Metals, Ltd.
    Inventors: Mitsutoshi Natsumeda, Yoshinori Takayama, Motoharu Shimizu
  • Patent number: 8377233
    Abstract: A method for preparing a rare earth permanent magnet material comprises the steps of: disposing a powder comprising one or more members selected from an oxide of R2, a fluoride of R3, and an oxyfluoride of R4 wherein R2, R3 and R4 each are one or more elements selected from among rare earth elements inclusive of Y and Sc on a sintered magnet form of a R1—Fe—B composition wherein R1 is one or more elements selected from among rare earth elements inclusive of Y and Sc, and then heat treating the magnet form and the powder at a temperature equal to or below the sintering temperature of the magnet in vacuum or in an inert gas. The result high performance, compact or thin permanent magnet has a high remanence and coercivity at a high productivity.
    Type: Grant
    Filed: February 24, 2011
    Date of Patent: February 19, 2013
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hajime Nakamura, Koichi Hirota, Takehisa Minowa
  • 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: 8323422
    Abstract: Provided is a dust core excellent in flux density, iron loss, and mechanical strength. A production process of a dust core according to the invention includes a step of compacting a mixture obtained by mixing an iron-based soft magnetic powder for powder compact having a phosphate conversion coating film on the surface of an iron-based soft magnetic powder with a lubricant to obtain a powder compact, a heat treatment step of heating the resulting powder compact at 550° C. or more but not more than 650° C. in an inert atmosphere, and a heat treatment step of heating the heat-treated powder compact at 420° C. or more but not more than 530° C. in an oxidizing atmosphere.
    Type: Grant
    Filed: November 22, 2011
    Date of Patent: December 4, 2012
    Assignee: Kobe Steel, Ltd.
    Inventors: Takeshi Ohwaki, Hiroyuki Mitani, Hirofumi Hojo, Tomotsuna Kamijo
  • Patent number: 8317937
    Abstract: In order to make a sintered R-T-B-M magnet so that R2T14B phases that include a lot of Dy in the surface region of the main phase are distributed over the entire magnet, a region including a heavy rare-earth element RH at a high concentration is formed continuously beforehand at an interface between the crystals of an R2T14B compound that is the main phase of the sintered R-T-B-M magnet and the other phases.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: November 27, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventor: Futoshi Kuniyoshi
  • Patent number: 8303732
    Abstract: A rare earth magnet having a composition represented by RTB wherein R denotes a rare earth element, T a transition metal and B boron, the magnet being composed of magnet powder constituted by crystalline particles. The particles of the magnetic powder have a ratio of a short diameter being 10 ?m or more to a long diameter is 0.5 or less. An element Rm having a magnetic anisotropy higher than that of the rare earth element is contained in the surface and inside of the magnet constituted by the magnet powder in an approximately constant concentration. An oxy-fluoride and carbon are present at boundaries of the particles of the magnet powder.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: November 6, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Suzuki, Takao Imagawa, Yuichi Satsu, Matahiro Komuro
  • Patent number: 8277578
    Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
    Type: Grant
    Filed: October 27, 2010
    Date of Patent: October 2, 2012
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
  • Patent number: 8268093
    Abstract: An R—Fe—B based porous magnet according to the present invention has an aggregate structure of Nd2Fe14B type crystalline phases with an average grain size of 0.1 ?m to 1 ?m. At least a portion of the magnet is porous and has micropores with a major axis of 1 ?m to 20 ?m.
    Type: Grant
    Filed: May 18, 2007
    Date of Patent: September 18, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Takeshi Nishiuchi, Noriyuki Nozawa, Satoshi Hirosawa, Tomohito Maki, Katsunori Bekki
  • Patent number: 8262808
    Abstract: There is provided a method of manufacturing a permanent magnet which has an extremely high coercive force and high magnetic properties is manufactured at high productivity. There are executed: a first step of causing at least one of Dy and Tb to adhere to at least part of a surface of iron-boron-rare-earth based sintered magnet; and a second step of diffusing, through heat-treatment at a predetermined temperature, at least one of Dy and Tb adhered to the surface of the sintered magnet into grain boundary phase of the sintered magnet.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: September 11, 2012
    Assignee: ULVAC, Inc.
    Inventors: Hiroshi Nagata, Kyuzo Nakamura, Takeo Katou, Atsushi Nakatsuka, Ichirou Mukae, Masami Itou, Ryou Yoshiizumi, Yoshinori Shingaki
  • Patent number: 8252124
    Abstract: The present invention provides a powder magnetic core low in the loss and high in the saturation magnetic flux density and a method for manufacturing the same. More specifically, the present invention provides a powder magnetic core that comprises a soft magnetic metal powder having an average particle size (D50) of 0.5 to 5 ?m, a half width of diffraction peak in a <110> direction of ?-Fe as measured by X-ray powder diffraction of 0.2 to 5.0°, and an Fe content of 97.0% by mass or more, the core having an oxygen content of 2.0% by mass or more.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: August 28, 2012
    Assignee: TDK Corporation
    Inventors: Masahito Koeda, Tomofumi Kuroda, Tomokazu Ishikura, Akihiro Harada, Hiroyuki Ono, Osamu Kido, Satoko Ueda
  • Patent number: 8252123
    Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
    Type: Grant
    Filed: October 27, 2010
    Date of Patent: August 28, 2012
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
  • Patent number: 8231740
    Abstract: A rare earth permanent magnet material is prepared by covering a sintered magnet body of R1—Fe—B composition wherein R1 is a rare earth element, with a powder comprising at least 30% by weight of an alloy of R2aTbMcAdHe wherein R2 is a rare earth element, T is Fe and/or Co, and M is Al, Cu or the like, and having an average particle size up to 100 ?m, and heat treating the powder-covered magnet body at a suitable temperature, for causing R2, T, M and A in the powder to be absorbed in the magnet body.
    Type: Grant
    Filed: April 12, 2007
    Date of Patent: July 31, 2012
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hajime Nakamura, Takehisa Minowa, Koichi Hirota
  • Patent number: 8206516
    Abstract: In a method for producing an R—Fe—B based rare-earth sintered magnet according to the present invention, first, provided is an R—Fe—B based rare-earth sintered magnet body including, as a main phase, crystal grains of an R2Fe14B type compound that includes a light rare-earth element RL, which is at least one of Nd and Pr, as a major rare-earth element R. Thereafter, the sintered magnet body is heated while a heavy rare-earth element RH, which is at least one element selected from the group consisting of Dy, Ho and Tb, is supplied to the surface of the sintered magnet body, thereby diffusing the heavy rare-earth element RH into the rare-earth sintered magnet body.
    Type: Grant
    Filed: March 1, 2007
    Date of Patent: June 26, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Koshi Yoshimura, Hideyuki Morimoto, Tomoori Odaka
  • Patent number: 8187392
    Abstract: In an R—Fe—B based rare-earth sintered magnet according to the present invention, at a depth of 20 ?m under the surface of its magnet body, crystal grains of an R2Fe14B type compound have an (RL1-xRHx)2Fe14B (where 0.2?x?0.75) layer with a thickness of 1 nm to 2 ?m in their outer periphery. In this case, the light rare-earth element RL is at least one of Nd and Pr, and the heavy rare-earth element RH is at least one element selected from the group consisting of Dy, Ho and Tb.
    Type: Grant
    Filed: July 1, 2008
    Date of Patent: May 29, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Koshi Yoshimura, Hideyuki Morimoto, Tomoori Odaka
  • Patent number: 8182619
    Abstract: First, an R—Fe—B based rare-earth sintered magnet body including, as a main phase, crystal grains of an R2Fe14B type compound that includes a light rare-earth element RL, which is at least one of Nd and Pr, as a major rare-earth element R is provided. Next, an M layer, including a metallic element M that is at least one element selected from the group consisting of Al, Ga, In, Sn, Pb, Bi, Zn and Ag, is deposited on the surface of the sintered magnet body and then an RH layer, including a heavy rare-earth element RH that is at least one element selected from the group consisting of Dy, Ho and Tb, is deposited on the M layer. Thereafter, the sintered magnet body is heated, thereby diffusing the metallic element M and the heavy rare-earth element RH from the surface of the magnet body deeper inside the magnet.
    Type: Grant
    Filed: July 5, 2011
    Date of Patent: May 22, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hideyuki Morimoto, Tomoori Odaka, Masao Noumi
  • Patent number: 8177922
    Abstract: An R—Fe—B based anisotropic sintered magnet according to the present invention has, as a main phase, an R2Fe14B type compound that includes a light rare-earth element RL (which is at least one of Nd and Pr) as a major rare-earth element R, and also has a heavy rare-earth element RH (which is at least one element selected from the group consisting of Dy and Tb). In the crystal lattice of the main phase, the c-axis is oriented in a predetermined direction. The magnet includes a portion in which at least two peaks of diffraction are observed within a 2? range of 60.5 degrees to 61.5 degrees when an X-ray diffraction measurement is carried out using a CuK ? ray on a plane that is located at a depth of 500 ?m or less under a pole face of the magnet and that is parallel to the pole face.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: May 15, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Tomoori Odaka, Hideyuki Morimoto, Kohshi Yoshimura, Shigeru Takaki
  • Patent number: 8177921
    Abstract: An R—Fe—B based rare-earth sintered magnet according to the present invention includes, as a main phase, crystal grains of an R2Fe14B type compound that includes Nd, which is a light rare-earth element, as a major rare-earth element R. The magnet includes a heavy rare-earth element RH (which is at least one of Dy and Tb) that has been introduced through the surface of the sintered magnet by diffusion. The magnet has a region in which the concentration of the heavy rare-earth element RH in a grain boundary R-rich phase is lower than at the surface of the crystal grains of the R2Fe14B type compound but higher than at the core of the crystal grains of the R2Fe14B type compound.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: May 15, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Tomoori Odaka, Hideyuki Morimoto, Kohshi Yoshimura, Shigeru Takaki, Shinichiro Sakashita
  • Patent number: 8128759
    Abstract: By causing at least one of Dy and Tb to be adhered to the surface of an iron-boron-rare earth based sintered magnet of a predetermined shape, and is then to be diffused into grain boundary phase, a permanent magnet can be manufactured at high workability and low cost. An iron-boron-rare earth based sintered magnet is disposed in a processing chamber and is heated to a predetermined temperature. Also, an evaporating material made up of a fluoride containing at least one of Dy and Tb disposed in the same or another processing chamber is evaporated, and the evaporated evaporating material is caused to be adhered to the surface of the sintered magnet. The Dy and/or Tb metal atoms of the adhered evaporating material are diffused into the grain particle phase of the sintered magnet before a thin film made of the evaporated material is formed on the surface of the sintered magnet.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: March 6, 2012
    Assignee: Ulvac, Inc.
    Inventors: Hiroshi Nagata, Kyuzo Nakamura, Takeo Katou, Atsushi Nakatsuka, Ichirou Mukae, Masami Itou, Ryou Yoshiizumi, Yoshinori Shingaki
  • Patent number: 8128758
    Abstract: An R—Fe—B based rare-earth alloy powder with a mean particle size of less than about 20 ?m is provided and compacted to make a powder compact. Next, the powder compact is subjected to a heat treatment at a temperature of about 550° C. to less than about 1,000° C. within hydrogen gas, thereby producing hydrogenation and disproportionation reactions (HD processes). Then, the powder compact is subjected to another heat treatment at a temperature of about 550° C. to less than about 1,000° C. within either a vacuum or an inert atmosphere, thereby producing desorption and recombination reactions and obtaining a porous material including fine crystal grains, of which the density is about 60% to about 90% of their true density and which have an average crystal grain size of about 0.01 ?m to about 2 ?m (DR processes). Thereafter, the porous material is subjected to yet another heat treatment at a temperature of about 750° C. to less than about 1,000° C.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: March 6, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Noriyuki Nozawa, Takeshi Nishiuchi, Satoshi Hirosawa, Tomohito Maki
  • Patent number: 8128760
    Abstract: By eliminating the necessity of a prior step for cleaning a sintered magnet before adhering Dy and/or Tb to the surface of the sintered magnet S, the productivity of a permanent magnet having diffused Dy and/or Tb into grain boundary phase is improved. Iron-boron-rare earth based sintered magnet (S) disposed in a processing chamber (20) is heated to a predetermined temperature. An evaporating material (V) which is made of a hydride containing at least one of Dy and Tb is disposed in the same or in another processing chamber and is evaporated to cause the evaporated evaporating material to the surface of the sintered magnet. Metal atoms of Dy and/or Tb are diffused into grain boundary phase of the sintered magnet.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: March 6, 2012
    Assignee: Ulvac, Inc.
    Inventors: Hiroshi Nagata, Kyuzo Nakamura, Takeo Katou, Atsushi Nakatsuka, Ichirou Mukae, Masami Itou, Ryou Yoshiizumi, Yoshinori Shingaki
  • Patent number: 8125338
    Abstract: An acousto-magnetic (AM) anti-theft alarming unit is designed for specific use in a hard tag anti-theft clamp which uses a magnetic detacher. The alarming unit includes a resonator housing defining a cavity in which is placed at least one resonator and a bias piece covered by a housing cover affixed to the resonator housing. The resonators are placed into the housing cavity in a vertically layered configuration. The bias piece is placed along the side of the resonators, as opposed to being beneath the resonators, as is conventional in the art. The bias piece is preferably made of a sintered rare-earth permanent magnet and has a high coercivity. Accordingly, this alarming unit has a strong resistance to demagnetization and a resistance to being shielded by metal. The bias piece has a strong anti-destruction ability, a simple structure and is easy to manufacture.
    Type: Grant
    Filed: June 24, 2009
    Date of Patent: February 28, 2012
    Assignee: Ningbo Signatronic Technologies, Ltd.
    Inventor: Lin Li
  • Patent number: 8075707
    Abstract: A method for preparing a rare earth permanent magnet material comprises the steps of disposing a powder on a surface of a sintered magnet body of R1aTbAcMd composition wherein R1 is a rare earth element inclusive of Sc and Y, T is Fe and/or Co, A is boron (B) and/or carbon (C), M is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr, Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, or W, said powder comprising an oxide of R2, a fluoride of R3 or an oxyfluoride of R4 wherein R2, R3, and R4 are rare earth elements inclusive of Sc and Y and having an average particle size equal to or less than 100 ?m, heat treating the magnet body and the powder at a temperature equal to or below the sintering temperature of the magnet body for absorption treatment for causing R2, R3, and R4 in the powder to be absorbed in the magnet body, and repeating the absorption treatment at least two times.
    Type: Grant
    Filed: March 28, 2007
    Date of Patent: December 13, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hajime Nakamura, Takehisa Minowa, Koichi Hirota
  • Patent number: 8075710
    Abstract: A process for the manufacture of soft magnetic composite components is provided including the steps of: die compacting a powder composition including a mixture of soft magnetic, iron or iron-based powder, core particles of which are surrounded by an electrically insulating, inorganic coating, and an organic lubricant in an amount of 0.05 to 1.5% by weight of the composition, the organic lubricant being free from metal and having a temperature of vaporization less than the decomposition temperature of the coating; ejecting the compacted body from the die; heating the compacted body in an inert atmosphere to a temperature above the vaporization temperature of the lubricant and below the decomposition temperature of the inorganic coating for removing the lubricant from the compacted body, and subjecting the body obtained after heating the compacted body in an inert atmosphere to heat treatment at a temperature between 300 and 600 in water vapor.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: December 13, 2011
    Assignee: Höganäs AB
    Inventors: Björn Skårman, Zhou Ye, Patricia Jansson
  • Patent number: 8038807
    Abstract: First, an R—Fe—B based rare-earth sintered magnet body including, as a main phase, crystal grains of an R2Fe14B type compound that includes a light rare-earth element RL, which is at least one of Nd and Pr, as a major rare-earth element R is provided. Next, an M layer, including a metallic element M that is at least one element selected from the group consisting of Al, Ga, In, Sn, Pb, Bi, Zn and Ag, is deposited on the surface of the sintered magnet body and then an RH layer, including a heavy rare-earth element RH that is at least one element selected from the group consisting of Dy, Ho and Tb, is deposited on the M layer. Thereafter, the sintered magnet body is heated, thereby diffusing the metallic element M and the heavy rare-earth element RH from the surface of the magnet body deeper inside the magnet.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: October 18, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hideyuki Morimoto, Tomoori Odaka, Masao Noumi
  • Patent number: 8025744
    Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: September 27, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
  • Patent number: 7985303
    Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
    Type: Grant
    Filed: October 27, 2010
    Date of Patent: July 26, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
  • Patent number: 7985305
    Abstract: A polymeric quenchant. The polymeric quenchant comprises an inorganic nanoparticle, a water-soluble polymer, and water, wherein a weight ratio of the inorganic nanoparticle, water-soluble polymer and water is about 0.05-5:1-5:100. The cooling rate of steel during a quenching process can be adjusted by regulating the components and ratios of the adjusted by regulating the components and ratios of the polymeric quenchant to achieve desirable steel properties.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: July 26, 2011
    Assignees: Industrial Technology Research Institute, Gelie Co., Ltd.
    Inventors: George Ho, Li-Kuei Lin, Wen-Faa Kuo
  • Patent number: 7972448
    Abstract: Disclosed herein is a method for the production of an anisotropic magnetic powder or a magnet produced from said powder, wherein a hydrogenating and dehydrogenating method is applied to the starting material in order to produce the powder. An anisotropic oriented magnetic material, more particularly magnetic scrap metal, is advantageously used as starting material so that the complicated use of a molten mass with isotropic distribution of the c axes of the hard metal crystals is not required. The result is an anisotropic material having a fine grain structure and a crystallographic orientation matching a TMXB phase formed during hydrogenation.
    Type: Grant
    Filed: November 27, 2003
    Date of Patent: July 5, 2011
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventor: Georg Werner Reppel
  • Patent number: 7955443
    Abstract: A permanent magnet material is prepared by covering an anisotropic sintered magnet body of formula: R1x(Fe1-yCoy)100-x-z-aBzMa wherein R1 is a rare earth element, M is Al, Cu or the like, with a powder comprising an oxide of R2, a fluoride of R3 or an oxyfluoride of R4 wherein R2, R3, and R4 are rare earth elements, and having an average particle size up to 100 ?m, heat treating the powder-covered magnet body in a hydrogen gas-containing atmosphere for inducing disproportionation reaction on R12Fe14B compound, and continuing heat treatment at a reduced hydrogen gas partial pressure for inducing recombination reaction to said compound, thereby finely dividing said compound phase to a crystal grain size up to 1 ?m, and for effecting absorption treatment, thereby causing R2, R3 or R4 to be absorbed in the magnet body.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: June 7, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hajime Nakamura, Takehisa Minowa, Koichi Hirota
  • 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
  • Patent number: 7922832
    Abstract: A permanent magnet material is prepared by machining an anisotropic sintered magnet body having the compositional formula: Rx(Fe1-yCoy)100-x-z-aBzMa wherein R is Sc, Y or a rare earth element, M is Al, Cu or the like, to a specific surface area of at least 6 mm?1, heat treating in a hydrogen gas-containing atmosphere at 600-1,100° C. for inducing disproportionation reaction on the R2Fe14B compound, and continuing heat treatment at a reduced hydrogen gas partial pressure and 600-1,100° C. for inducing recombination reaction to the R2Fe14B compound, thereby finely dividing the R2Fe14B compound phase to a crystal grain size ?1 ?m.
    Type: Grant
    Filed: April 6, 2007
    Date of Patent: April 12, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hajime Nakamura, Takehisa Minowa
  • Patent number: 7914695
    Abstract: The object of the present invention is to both reduce costs and improve magnetic characteristics of rare-earth bond magnets in which magnetic material is bound with a binding agent. In order to achieve this object, magnetic characteristics of a magnet are improved by performing cold forming on rare-earth magnetic powder by itself with no resin added. Then, in order to provide strength for the magnet, a low-viscosity SiO2 precursor is infiltrated and thermoset in the magnet shaped body. As a result, it is possible to obtain a rare-earth bond magnet in which magnetic characteristics are improved and costs are reduced.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: March 29, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Yuichi Satsu, Matahiro Komuro, Takao Imagawa, Takashi Yasuhara, Yutaka Matsunobu
  • Patent number: 7883587
    Abstract: A rare earth permanent magnet is prepared by providing a sintered magnet body consisting of 12-17 at % of rare earth, 3-15 at % of B, 0.01-11 at % of metal element, 0.1-4 at % of O, 0.05-3 at % of C, 0.01-1 at % of N, and the balance of Fe, disposing on a surface of the magnet body a powder comprising an oxide, fluoride and/or oxyfluoride of another rare earth, and heat treating the powder-covered magnet body at a temperature below the sintering temperature in vacuum or in an inert gas, for causing the other rare earth to be absorbed in the magnet body.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: February 8, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hajime Nakamura, Koichi Hirota, Takehisa Minowa
  • Patent number: 7871474
    Abstract: A method for manufacturing bodies formed from insulated soft magnetic metal powder by forming an insulating film of an inorganic substance on the surface of particles of a soft magnetic metal powder, compacting and molding the powder, then carrying out a heat treatment to provide a body formed from insulated soft magnetic metal powder the method comprising: compacting and molding the powder; then magnetically annealing the powder at a high temperature above the Curie temperature for the soft magnetic metal powder and below the threshold temperature at which the insulating film is destroyed in a non-oxidizing atmosphere, such as a vacuum, inert gas, or the like; and then carrying out a further heat treatment at a temperature of from 400° C. to 700° C. in an oxidizing atmosphere, such as air, or the like.
    Type: Grant
    Filed: July 3, 2006
    Date of Patent: January 18, 2011
    Assignee: Mitsubishi Steel Mfg. Co. Ltd.
    Inventors: Kenichi Unoki, Kenichi Nagai, Shoichi Yamasaki, Yuji Soda
  • Patent number: 7824506
    Abstract: In known methods, an improvement of the coercive force is realized by allowing the Dy metal or the like to present selectively in crystal grain boundary portions of a sintered magnet. However, since these are based on a physical film formation method, e.g., sputtering, through the use of a vacuum vessel, there is a mass productivity problem when a large number of magnets are treated. Furthermore, there is a magnet cost problem from the viewpoint that, for example, an expensive, high-purity Dy metal or the like must be used as a raw material for film formation. The method for modifying grain boundaries of a Nd—Fe—B base magnet includes the step of allowing an M metal component to diffuse and penetrate from a surface of a Nd—Fe—B base sintered magnet body having a Nd-rich crystal grain boundary phase surrounding principal Nd2Fe14B crystals to the grain boundary phase through a reduction treatment of a fluoride, an oxide, or a chloride of an M metal element (where M is Pr, Dy, Tb, or Ho).
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: November 2, 2010
    Assignees: Japan Science and Technology Agency, Osaka University
    Inventors: Kenichi Machida, Shunji Suzuki
  • Patent number: 7819988
    Abstract: A method for processing CoPt alloys with improved magnetic properties. The method includes sealing a sample of a CoPt alloy in an evacuated quartz tube, and heating the alloy to a temperature of approximately 1000 degrees C. to homogenize the alloy for approximately 3 hours. The sample is then cooled at a controlled cooling rate of 120-150 degrees C. per minute to 600 degrees C. The sample is then held at 600 degrees C. for 10 hours to promote isothermal ordering. Finally, the sample is quenched in mineral oil.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: October 26, 2010
    Assignee: Florida State University Research Foundation
    Inventors: Baozhi Cui, Ke Han
  • Patent number: 7815752
    Abstract: Disclosed is a novel process for producing an NaZn13 magnetic alloy which enables to obtain a magnetic alloy having higher characteristics than ever before. Specifically disclosed is a magnetic alloy represented by the following composition formula: (La1?xRx)a(A1?yTMy)bHcNd (wherein R represents at least one or more elements selected from rare earth elements including Y; A represents Si, or Si and at least one or more elements selected from the group consisting of Al, Ga, Ge and Sn; TM represents Fe, or Fe and at least one or more elements selected from the group consisting of Sc, Ti, V, Cr, Mn, Co, Ni, Cu and Zn; and x, y, a, b, c and d respectively satisfy, in atomic percent, the following relations: 0?x?0.2, 0.75?y?0.92, 5.5 ?a?7.5, 73?b?85, 1.7?c?14 and 0.07?d<5.0; with unavoidable impurities being included).
    Type: Grant
    Filed: April 4, 2006
    Date of Patent: October 19, 2010
    Assignee: Hitachi Metals, Ltd.
    Inventor: Shigeho Tanigawa
  • Patent number: 7736444
    Abstract: Grain oriented electrical steel is made in a manner that the grains are selectively grown to obtain a crystal structure known as cube-on-edge and the grains are largely aligned in the rolling direction. Selection of chemistry and process route along with thin slab continuous casting enables the production of Grain oriented electrical steel such that less energy is consumed in the process, certain process steps can be combined, yield is better and the product can be manufactured within a wider process control tolerance.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: June 15, 2010
    Assignee: Silicon Steel Technology, Inc.
    Inventors: Vladimir Pavlovich Shumilov, Alexandr G. Shalimov, Leonard Mironov, Urij Christiakov
  • Patent number: 7727644
    Abstract: In a grain-oriented electrical steel sheet having phosphate-based coatings, which contain no chromium and which impart a tension, on the surfaces of a steel sheet with ceramic underlying films therebetween, the coating amount of oxygen in the underlying film is 2.0 g/m2 or more and 3.5 g/m2 or less relative to both surfaces of the steel sheet. Consequently, a grain-oriented electrical steel sheet with a chromium-less coating is provided. The resulting steel sheet has coating properties at the same level as those of a steel sheet with chromium-containing coatings and realizes high hygroscopicity resistance and a low iron loss without variations.
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: June 1, 2010
    Assignee: JFE Steel Corporation
    Inventors: Makoto Watanabe, Hiroaki Toda, Mineo Muraki
  • Patent number: 7632360
    Abstract: A rare earth magnet powder has a chemical composition which includes R: 5 to 20% (wherein, R represents one or two or more rare earth elements being inclusive of Y but exclusive of Dy and Tb), one or two of Dy and Tb: 0.01 to 10%, and B: 3 to 20%, with the balance comprising Fe and inevitable impurities; and an average particle diameter of 10 to 1,000 ?m, wherein 70% or more of the entire surface of the rare earth magnet powder is covered with a layer being rich in the content of one or two of Dy and Tb and having a thickness of 0.05 to 50 ?m.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: December 15, 2009
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Katsuhiko Mori, Ryoji Nakayama, Hideaki Ono, Takae Ono, legal representative, Tetsurou Tayu, Munekatsu Shimada, Makoto Kano, Yoshio Kawashita
  • Patent number: 7608153
    Abstract: A rare earth magnet includes rare earth magnet particles; and amorphous and/or crystalline terbium oxide present at the boundary of the rare earth magnet particles and represented by the formula: TbOn, wherein 1.5<n?2. The rare earth magnet prevents decrease eddy current effectively.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: October 27, 2009
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Tetsurou Tayu, Hideaki Ono, Takae Ono, legal representative, Yoshio Kawashita, Makoto Kano, Munekatsu Shimada