Rare Earth And Transition Metal Containing Patents (Class 148/301)
  • Publication number: 20080124235
    Abstract: [Object] To improve resistance of a motor device against an organic solvent and to suppress degradation in performance of the motor device with time. [Solving Means] In a motor device, an excitation magnet is formed using a hollow-cylinder shaped anisotropic bonded magnet 13. This bonded magnet 13 is press-fitted in a housing 12 and is held. The bonded magnet 13 is formed of a hollow-cylinder shaped anisotropic rare earth bonded magnet which is obtained by compounding an anisotropic rare earth magnet powder with a phenol-novolac type epoxy resin, followed by molding. The anisotropic rare earth bonded magnet 13 is press-fitted along an inner peripheral portion of the housing 12, and on an exposed surface layer of the anisotropic rare earth bonded magnet press-fitted in the housing, a coating layer is formed by an infiltration treatment using a polyamide-imide-based resin.
    Type: Application
    Filed: November 29, 2005
    Publication date: May 29, 2008
    Inventors: Yoshinobu Honkura, Hiroshi Matsuoka, Atsushi Kano, Kenji Noguchi, Hironari Mitarai, Satoru Kan
  • Publication number: 20080053573
    Abstract: A rare earth magnet having excellent corrosion resistance is provided. It has a magnet body (10) containing a rare earth element, and a protective film (20) formed on the magnet body (10). In the protective film (20), a first protective film (21), a second protective film (22) and a third protective film (23) are laminated in this order from the side of the magnet body (10). These are in a polycrystalline state and composed of a metal plated film, for example. The first protective film (21) and the third protective film (23) have a smaller mean crystal grain size than that of the second protective film (22). Microcrystallization of the first protective film (21) can improve the density of the interface between the protective film (20) and the magnet body (10), and decrease the number of pinholes.
    Type: Application
    Filed: July 19, 2005
    Publication date: March 6, 2008
    Applicant: TDK CORPORATION
    Inventors: Takeshi Sakamoto, Nobuya Uchida, Yoshitomo Tanaka, Yasuyuki Nakayama
  • Patent number: 7316752
    Abstract: The step of preparing a rapidly solidified alloy by rapidly quenching a melt of an R-T-B-C based rare-earth alloy (where R is at least one of the rare-earth elements including Y, T is a transition metal including iron as its main ingredient, B is boron, and C is carbon) and the step of thermally treating and crystallizing the rapidly solidified alloy are included. The step of thermally treating results in producing a first compound phase with an R2Fe14B type crystal structure and a second compound phase having a diffraction peak at a site with an interplanar spacing d of 0.295 nm to 0.300 nm (i.e., where 2?=30 degrees). An intensity ratio of the diffraction peak of the second compound phase to that of R2Fe14B type crystals representing a (410) plane is at least 10%. The present invention provides an R-T-B-C based rare-earth alloy magnetic material, including carbon (C) as an indispensable element but exhibiting excellent magnetic properties, and makes it possible to recycle rare-earth magnets.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: January 8, 2008
    Assignee: Neomax Co., Ltd.
    Inventors: Hiroyuki Tomizawa, Yuji Kaneko
  • Patent number: 7309396
    Abstract: Restoring magnetostriction characteristics without causing fusion of rod. By performing heat treatment on a giant magnetostrictive material within the temperature range of 750 to 860° C., working distortion is removed while bleeding of an R-rich phase on a rod surface is prevented.
    Type: Grant
    Filed: February 10, 2003
    Date of Patent: December 18, 2007
    Assignee: TDK Corporation
    Inventors: Teruo Mori, Shiro Tomizawa
  • Patent number: 7297213
    Abstract: An iron-based rare earth alloy magnet has a composition represented by the general formula: (Fe1-mTm)100-x-y-zQxRyMz, where T is at least one element selected from the group consisting of Co and Ni; Q is at least one element selected from the group consisting of B and C; R is at least one rare earth element substantially excluding La and Ce; and M is at least one metal element selected from the group consisting of Ti, Zr and Hf and always includes Ti. In this formula, the mole fractions x, y, z and m meet the inequalities of: 10 at %<x?20 at %; 6 at %?y<10 at %; 0.1 at %?z?12 at %; and 0?m?0.5, respectively.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: November 20, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa, Yasutaka Shigemoto, Yusuke Shioya
  • Patent number: 7273405
    Abstract: A method of producing a sintered rare earth magnetic alloy wafer comprises a step of using a cutter to slice a wafer of a thickness of not greater than 3 mm from a sintered rare earth magnetic alloy having ferromagnetic crystal grains surrounded by a more readily grindable grain boundary phase and a step of surface-grinding at least one cut surface of the obtained wafer with a grindstone to form at a surface layer thereof flat ferromagnetic crystal grain cross-sections lying parallel to the wafer planar surface. The method enables high-yield production of a sintered rare earth magnetic alloy wafer having flat surfaces.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: September 25, 2007
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Kiyoshi Yamada, Hirofumi Takei, Masami Kamada, Toshinori Eba
  • Patent number: 7261781
    Abstract: A nanocomposite magnet has a composition represented by (Fe1-mTm)100-x-y-z-nQxRyTizMn, where T is at least one of Co and Ni, Q is at least one of B and C, R is at least one rare earth element that always includes at least one of Nd and Pr and optionally includes Dy and/or Tb, and M is at least one element selected from the group consisting of Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. The mole fractions x, y, z, m and n satisfy 10 at %<x?20 at %, 6 at %?y<10 at %, 0.5 at %?z?12 at %, 0?m?0.5 and 0 at %?n?10 at %, respectively. The nanocomposite magnet has an oxygen content of at most about 1,500 ppm by mass.
    Type: Grant
    Filed: November 19, 2002
    Date of Patent: August 28, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Patent number: 7255830
    Abstract: To make a three-dimensional object, an optical beam is first irradiated on a predetermined portion of a powder layer to form a sintered layer, which is then covered with a new powder layer. The optical beam is again irradiated on a predetermined portion of the new powder layer to form another sintered layer that has been united with the underlying sintered layer. These processes are repeatedly carried out to form a plurality of sintered layers united together. When the second lower density layer is formed on the first higher density layer, a powder material layer for the lower density layer is formed at a predetermined thickness so as to have a thickness suitable for sintering condition and then the powder material layer is sintered to form the lower density layer.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: August 14, 2007
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Satoshi Abe, Isao Fuwa, Hirohiko Togeyama, Norio Yoshida, Masataka Takenami, Shuushi Uenaga
  • Patent number: 7232495
    Abstract: The method of the present invention includes a step of preparing a rare earth magnet 22 disposed for forming a cylinder 22a, a first magnetizing step of applying a first external magnetic field H1 to the rare earth magnet 22, thereby forming a first region R1 magnetized from an inner side to an outer side of the cylinder 22a and a second region R2 magnetized from the outer side to the inner side, and a second magnetizing step of applying a second external magnetic field H2 so that an external magnetic field component forming an angle of more than 0° and less than 50° with a direction of the external magnetic field component applied in the first magnetizing step to a boundary between the first region R1 and the second region R2.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: June 19, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Eiji Sakaguchi, Hitoshi Morimoto
  • Patent number: 7217328
    Abstract: A compound for a rare-earth bonded magnet includes a rare-earth alloy powder and a binder. The rare-earth alloy powder includes at least about 2 mass % of Ti-containing nanocomposite magnet powder particles with a composition represented by (Fe1-mTm)100-x-y-zQxRyMz, where T is Co and/or Ni; Q is B with or without C; R is at least one rare-earth element substantially excluding La and Ce; M is at least one metal element selected from Ti, Zr and Hf and always includes Ti; and 10<x?20 at %; 6?y<10 at %; 0.1?z?12 at %; and 0?m?0.5. The particles include at least two ferromagnetic crystalline phases, in which hard magnetic phases have an average crystal grain size of about 10 nm to about 200 nm, soft magnetic phases have an average crystal grain size of about 1 nm to about 100 nm; and the average crystal grain size of the soft magnetic phases is smaller than that of the hard magnetic phases.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: May 15, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Takeshi Nishiuchi, Hirokazu Kanekiyo, Satoshi Hirosawa, Toshio Miyoshi
  • Patent number: 7186303
    Abstract: A method of making a magnetic alloy material includes the steps of: preparing a melt of an alloy material having a predetermined composition; rapidly cooling and solidifying the melt to obtain a rapidly solidified alloy represented by: Fe100-a-b-cREaAbTMc where RE is at least one rare-earth element selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er and Tm and including at least about 90 at % of La; A is at least one element selected from Al, Si, Ga, Ge and Sn; TM is at least one transition metal element selected from Sc, Ti, V, Cr, Mn, Co, Ni, Cu and Zn; and 5 at %?a?10 at %, 4.7 at %?b?18 at % and 0 at %?c?9 at %; and producing a compound phase having an NaZn13-type crystal structure in at least about 70 vol % of the rapidly solidified alloy.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: March 6, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Ryosuke Kogure, Hirokazu Kanekiyo, Takeshi Nishiuchi, Satoshi Hirosawa
  • Patent number: 7179340
    Abstract: The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a potion of a grain boundary of Nd2Fe14B which is a main phase of an R—Fe—B (R is a rare-earth element) based magnet, and wherein the grain boundary phase contains a fluoride compound, and wherein a thickness of the fluoride compound is 10 ?m or less, or a thickness of the fluoride compound is from 0.1 ?m to 10 ?m, and wherein the coverage of the fluoride compound over a main phase particle is 50% or more on average.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: February 20, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Matahiro Komuro, Yuichi Satsu
  • Patent number: 7179339
    Abstract: A terbium-dysprosium-iron magnetostrictive material of the type Tb1-xDyxFe2-y wherein x is less than 0.7, and y is less than or equal to 0.1, and devices using these materials.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: February 20, 2007
    Assignee: Energen, Inc.
    Inventors: Chiu-Ying Tai, Chandrashekhar H. Joshi
  • Patent number: 7147686
    Abstract: A rare earth magnet comprises rare earth magnet particles and a rare earth oxide being present between the rare earth magnet particles. The rare earth oxide is represented by a following general formula (I): R2O3??(I) where R is any one of terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.
    Type: Grant
    Filed: June 23, 2003
    Date of Patent: December 12, 2006
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Tetsurou Tayu, Hideaki Ono, Munekatsu Shimada, Makoto Kano
  • Patent number: 7114340
    Abstract: An alloy made of heat treated material represented by Gd5(SixGe1?x)4 where 0.47?x?0.56 that exhibits a magnetic entropy change (??Sm) of at least 16 J/kg K, a magnetostriction of at least 2000 parts per million, and a magnetoresistance of at least 5 percent at a temperature of about 300K and below, and method of heat treating the material between 800 to 1600 degrees C. for a time to this end.
    Type: Grant
    Filed: April 14, 2003
    Date of Patent: October 3, 2006
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Alexandra O. Pecharsky, Karl A. Gschneidner, Jr., Vitalij K. Pecharsky
  • Patent number: 7076958
    Abstract: The magnetic material for magnetic refrigeration of the present invention is characterized by exhibiting, in a certain temperature region, preferably, only in part of a temperature region from 200 K to 350 K, an inflection point at which a second order differential coefficient of a magnetization curve changes from positive to negative with respect to a magnetic field, within the range of this magnetic field formed using a permanent magnet unit. This magnetic material of the present invention can generate a low temperature by using a relatively low magnetic field, by transferring the entropy between the electron spin system and the lattice system near the temperature at which an inflection point appears on the magnetization curve. Examples of the magnetic material meeting this condition are La(Fe,Si)13, (Hf,Ta)Fe2, (Ti,Sc)Fe2, and (Nb,Mo)Fe2, each containing 50 to 60 atomic % of transition metals such as Fe.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: July 18, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akiko Saito, Tadahiko Kobayashi, Takao Sawa, Masashi Sahashi
  • Patent number: 7063754
    Abstract: The magnetic material for magnetic refrigeration according to the present invention has an NaZn13-type crystalline structure and comprises iron (Fe) as a principal element (more specifically, Fe is substituted for the position of “Zn”) and hydrogen (H) in an amount of 2 to 18 atomic % based on all constitutional elements. Preferably, the magnetic material for magnetic refrigeration preferably contains 61 to 87 atomic % of Fe, 4 to 18 atomic % of a total amount of Si and Al, 5 to 7 atomic % of La. The magnetic material for magnetic refrigeration exhibits a large entropy change in a room temperature region and no thermal hysteresis in a magnetic phase transition. Therefore, when a magnetic refrigeration cycle is configured using the magnetic material for magnetic refrigeration, a stable operation can be performed.
    Type: Grant
    Filed: April 1, 2003
    Date of Patent: June 20, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuaki Fukamichi, Asaya Fujita, Yoshiaki Iijima, Akiko Saito, Tadahiko Kobayashi, Masashi Sahashi
  • Patent number: 6984271
    Abstract: A rare earth magnet to be used in a motor. The rare earth magnet comprises rare earth magnet particles. Additionally, a rare earth oxide is present among the rare earth magnet particles, the rare earth oxide being represented by the following general formula (I): R2xR?2(1?x)O3??(I) where each of R and R? is one element selected from the group consisting of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu), and 0<x<1.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: January 10, 2006
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Tetsurou Tayu, Takae Ono, legal representative, Makoto Kano, Munekatsu Shimada, Yoshio Kawashita, Takeshi Yamauchi, Hideaki Ono, deceased
  • Patent number: 6864793
    Abstract: A magnetic marker comprises a magnetically switchable wire and a magnetic casing that covers the magnetically switchable wire. The magnetically switchable wire is formed of a magnetic material that undergoes occurrence of sharp magnetic inversion when an alternating field of intensity higher than its coercive force is applied to it. The magnetic casing is formed of a magnetically hard or semihard magnetic material and can apply a bias magnetic field to the magnetically switchable wire to prevent magnetic inversion of the magnetically switchable wire. Heat-treated portions and high-coercivity regions, which are not heat-treated, are formed alternately in the longitudinal direction on the magnetic casing. The heat-treated portions are given magnetic properties different from magnetic properties essential to the magnetic casing by heat treatment such as annealing.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: March 8, 2005
    Assignee: NHK Spring Co., Ltd.
    Inventors: Yoshiki Ono, Tatsuya Kurihara, Shigemi Sato, Sumikazu Oki
  • Publication number: 20040261420
    Abstract: A magnetocaloric effect heterostructure having a core layer of a giant magnetocaloric material and an elastically stiff material layer coated on at least one surface of the magnetocaloric material layer. The elastically stiff material layer restricts volume changes of the core layer during application of a magnetic field to the heterostructure. A magnetocaloric effect composite powder including a plurality of core particles of a giant magnetocaloric material. Each of the core particles is encapsulated within a coating of elastically stiff material that restricts volume changes of the core particles during application of a magnetic field thereto. A method for enhancing the magnetocaloric effect within a giant magnetocaloric material including the step of coating a surface of the magnetocaloric material with an elastically stiff material. The elastically stiff material restricts volume changes of the magnetocaloric material during application of a magnetic field thereto.
    Type: Application
    Filed: June 30, 2003
    Publication date: December 30, 2004
    Inventor: Laura J. Henderson Lewis
  • Patent number: 6830635
    Abstract: The present invention relates to spindle-shaped goethite particles having an average major axial diameter of 0.05 to 0.18 &mgr;m, spindle-shaped hematite particles having an average major axial diameter of 0.05 to 0.17 &mgr;m, spindle-shaped magnetic metal particles containing iron as a main component, which exhibit an adequate coercive force, good dispersibility, good oxidation stability and excellent coercive force distribution notwithstanding the average major axial diameter thereof is as small as 0.05 to 0.15 &mgr;m, and processes for producing the respective particles. Especially, the spindle-shaped magnetic metal particles containing iron as a main component, have an average major axial diameter of 0.05 to 0.15 &mgr;m, an aspect ratio of from 5:1 to 9:1, a size distribution (standard deviation/average major axial diameter) of not more than 0.30, a crystallite size D110 of 130 to 160 Å, a Co content of from 0.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: December 14, 2004
    Assignee: Toda Kogyo Corporation
    Inventors: Kenji Okinaka, Masayuki Uegami
  • Publication number: 20040244876
    Abstract: The present invention relates to a Sm—Co based magnet alloy useful as a raw material for producing magnets having high magnetic properties, such as sintered or bonded magnets, methods for producing such an alloy, and sintered or bonded magnets having excellent corrosion resistance and high magnetic properties, such as high coercivity and good squareness. The magnetic alloy is composed of an alloy represented by the formula RM with 32.5 to 35.5 wt % R such as Sm and the balance of M such as Co, wherein ratio (B/A) of the X-ray diffraction intensity (B) corresponding to the (119) plane of R2M7 phase to the X-ray diffraction intensity (A) corresponding to the (111) plane of RM5 phase is not higher than 0.1.
    Type: Application
    Filed: May 3, 2004
    Publication date: December 9, 2004
    Inventors: Kenji Konishi, Kazumasa Shintani
  • Publication number: 20040206422
    Abstract: The method of the present invention includes a step of preparing a rare earth magnet 22 disposed for forming a cylinder 22a, a first magnetizing step of applying a first external magnetic field H1 to the rare earth magnet 22, thereby forming a first region R1 magnetized from an inner side to an outer side of the cylinder 22a and a second region R2 magnetized from the outer side to the inner side, and a second magnetizing step of applying a second external magnetic field H2 so that an external magnetic field component forming an angle of more than 0° and less than 50 ° with a direction of the external magnetic field component applied in the first magnetizing step to a boundary between the first region R1 and the second region R2.
    Type: Application
    Filed: January 29, 2004
    Publication date: October 21, 2004
    Inventors: Eiji Sakaguchi, Hitoshi Morimoto
  • Publication number: 20040194855
    Abstract: The magnetic material for magnetic refrigeration according to the present invention has an NaZn13-type crystalline structure and comprises iron (Fe) as a principal element (more specifically, Fe is substituted for the position of “Zn”) and hydrogen (H) in an amount of 2 to 18 atomic % based on all constitutional elements. Preferably, the magnetic material for magnetic refrigeration preferably contains 61 to 87 atomic % of Fe, 4 to 18 atomic % of a total amount of Si and Al, 5 to 7 atomic % of La. The magnetic material for magnetic refrigeration exhibits a large entropy change in a room temperature region and no thermal hysteresis in a magnetic phase transition. Therefore, when a magnetic refrigeration cycle is configured using the magnetic material for magnetic refrigeration, a stable operation can be performed.
    Type: Application
    Filed: April 1, 2003
    Publication date: October 7, 2004
    Inventors: Kazuaki Fukamichi, Asaya Fujita, Yoshiaki Iijima, Akiko Saito, Tadahiko Kobayashi, Masashi Sahashi
  • Publication number: 20040187963
    Abstract: A rare earth magnet to be used in a motor. The rare earth magnet comprises rare earth magnet particles.
    Type: Application
    Filed: March 26, 2004
    Publication date: September 30, 2004
    Applicant: NISSAN MOTOR CO. LTD.
    Inventors: Tetsurou Tayu, Hideaki Ono, Takae Ono, Makoto Kano, Munekatsu Shimada, Yoshio Kawashita, Takeshi Yamauchi
  • Patent number: 6783608
    Abstract: Secondary agglomerates of magnetic metal particles for magnetic recording, have a sodium content of not more than 20 ppm and a calcium content of not more than 40 ppm, an average particle diameter of 300 to 800 &mgr;m and an upper limit of particle diameters of 2,000 &mgr;m, and comprise magnetic metal primary particles having an average major axis diameter of 0.05 to 0.25 &mgr;m.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: August 31, 2004
    Assignee: Toda Kogyo Corporation
    Inventors: Kenji Okinaka, Kohji Mori, Masayuki Uegami
  • Publication number: 20040149357
    Abstract: A solid material for a magnet, comprising a rare-earth/iron/nitrogen/hydrogen system magnetic material.
    Type: Application
    Filed: October 22, 2003
    Publication date: August 5, 2004
    Inventors: Etsuji Kakimoto, Kiyotaka Dohke, Ichiro Shibasaki, Nobuyoshi Imaoka, Akira Chiba
  • Publication number: 20040144450
    Abstract: Disclosed is an isotropic SmFeN powdery magnet material for producing resin-bonded magnets.
    Type: Application
    Filed: January 20, 2004
    Publication date: July 29, 2004
    Inventors: Takahiko Iriyama, Ryo Omatsuzawa, Takayuki Nishio
  • Patent number: 6758918
    Abstract: Disclosed is an isotropic SmFeN powdery magnet material for producing resin-bonded magnets. The magnet powder is prepared by melt-spinning of a molten alloy and nitriding the alloy powder thus obtained to form a magnet alloy having an alloy composition of one of the formulae, by atomic %: SmxFe100-x-vNv, SmxFe100-x-y-vM1yNv and SmxFe100-x-z-vM2zNv wherein M1 is at least one member selected from the group consisting of Hf and Zr; and M2 is at least one member selected from the group consisting of Si, Nb, Ti, Ga, Al, Ta and C; 7≦x≦12, 0.1≦y≦1.5, 0.1≦z≦1.0 and 0.5≦v≦20; the crystal structure is TbCu7 type; and the thickness of the flakes is 10-40 &mgr;m.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: July 6, 2004
    Assignee: Diado Steel Co., Ltd.
    Inventors: Takahiko Iriyama, Ryo Omatsuzawa, Takayuki Nishio
  • Publication number: 20040079446
    Abstract: A method of making a magnetic alloy material includes the steps of: preparing a melt of an alloy material having a predetermined composition; rapidly cooling and solidifying the melt to obtain a rapidly solidified alloy represented by: Fe100-a-b-cREaAbTMc where RE is at least one rare-earth element selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er and Tm and including at least about 90 at % of La; A is at least one element selected from Al, Si, Ga, Ge and Sn; TM is at least one transition metal element selected from Sc, Ti, V, Cr, Mn, Co, Ni, Cu and Zn; and 5 at %≦a≦10 at %, 4.7 at %≦b≦18 at % and 0 at %≦c≦9 at %; and producing a compound phase having an NaZn13-type crystal structure in at least about 70 vol % of the rapidly solidified alloy.
    Type: Application
    Filed: August 18, 2003
    Publication date: April 29, 2004
    Inventors: Ryosuke Kogure, Hirokazu Kanekiyo, Takeshi Nishiuchi, Satoshi Hirosawa
  • Patent number: 6726781
    Abstract: A permanent magnet is provided which retains its magnetic properties and exhibits a linear extrinsic demagnetization curve at elevated temperatures up to 700° C. The magnet is represented by the general formula RE(CoWFeVCuXTY)Z, where RE is a rare earth metal selected from the group consisting of Sm, Gd, Pr, Nd, Dy, Ce, Ho, Er, La, Y, Tb, and mixtures thereof and T represents a transition metal(s) selected from the group consisting of Zr, Hf, Ti, Mn, Cr, Nb, Mo, W, V, Ni, Ta, and mixtures thereof.
    Type: Grant
    Filed: September 12, 2002
    Date of Patent: April 27, 2004
    Assignees: University of Dayton, Electron Energy Corporation
    Inventors: Marlin S. Walmer, Christina H. Chen, Shiqiang Liu, Michael H. Walmer, G. Edward Kuhl
  • Publication number: 20040074564
    Abstract: Inductive component (10; 20; 30) having at least one coil (12; 22; 32) and a magnetically soft core (11; 21; 31) made from a ferromagnetic powder composite in which the ferromagnetic powder composite shows an alloy powder mixture made from alloy powders having formanisotropic as well as formisotropic powder particles and a casting resin.
    Type: Application
    Filed: November 7, 2003
    Publication date: April 22, 2004
    Inventor: Markus Brunner
  • Patent number: 6708388
    Abstract: A permanent magnet field-type compact DC motor having a high output and a low cogging torque is made by fixing a pair of rare earth magnets mainly composed of rare earth-iron-based rapidly quenched and solidified flakes to a soft magnetic frame so as to extend along an inner peripheral surface thereof, and by unsaturation-magnetizing the rare earth magnets so that demagnetization curves at circumferentially opposite end portions of the rare earth magnets are made smaller than a demagnetization curve at a central portion of a magnetic pole of each of the rare earth magnets.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: March 23, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Fumitoshi Yamashita, Shinji Toda, Eiji Uenishi, Yuichiro Sasaki
  • Publication number: 20040045637
    Abstract: A method for manufacturing a sintered magnet includes the steps of producing a green compact of powder for the sintered magnet, machining the green compact with a wire-saw, and sintering the green compact.
    Type: Application
    Filed: April 16, 2003
    Publication date: March 11, 2004
    Inventors: Atsuo Tanaka, Shoichi Matsugami, Tadahiro Iwasaki, Atsushi Ogawa, Hitoshi Morimoto
  • Publication number: 20040025974
    Abstract: Nanocrystalline and nanocomposite rare earth permanent magnet materials and methods for making the magnets are provided. The magnet materials can be isotropic or anisotropic and do not have a rare-earth rich phase. The magnet materials comprise nanometer scale grains and possesses a potential high maximum energy product, a high remancence, and a high intrinsic coercivity. The magnet materials having these properties are produced by using methods including magnetic annealing and rapid heat processing.
    Type: Application
    Filed: March 26, 2003
    Publication date: February 12, 2004
    Inventors: Don Lee, John Stanley Hilton, Baozhi Cui, Shiqiang Liu
  • Patent number: 6676772
    Abstract: The magnetic material for magnetic refrigeration of the present invention is characterized by exhibiting, in a certain temperature region, preferably, only in part of a temperature region from 200 K to 350 K, an inflection point at which a second order differential coefficient of a magnetization curve changes from positive to negative with respect to a magnetic field, within the range of this magnetic field formed using a permanent magnet unit. This magnetic material of the present invention can generate a low temperature by using a relatively low magnetic field, by transferring the entropy between the electron spin system and the lattice system near the temperature at which an inflection point appears on the magnetization curve. Examples of the magnetic material meeting this condition are La(Fe,Si)13, (Hf,Ta)Fe2, (Ti,Sc)Fe2, and (Nb,Mo)Fe2, each containing 50 to 60 atomic % of transition metals such as Fe.
    Type: Grant
    Filed: March 18, 2002
    Date of Patent: January 13, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akiko Saito, Tadahiko Kobayashi, Takao Sawa, Masashi Sahashi
  • Publication number: 20040003870
    Abstract: The present invention relates to a high performance rare earth-iron giant magnetostrictive material of the formula (Tbx1Dyx2Smx3Hox4Rx5)(Sy1Py2Fe1−y1−y2−y3Ty3)Q obtained by using an industry grade pure iron, instead of physically pure iron such as electrolyzed pure iron or hydrogen reduced pure iron, as iron source. The invention relates also to a method of preparing the giant magnetostrictive material.
    Type: Application
    Filed: October 31, 2002
    Publication date: January 8, 2004
    Inventor: Zheng Liu
  • Patent number: 6660178
    Abstract: Disclosed herein is a magnetic powder which can provide a bonded magnet having high mechanical strength and excellent magnetic properties. The magnetic powder has an alloy composition containing a rare-earth element and a transition metal, wherein the magnetic powder includes particles each of which is formed with a number of ridges or recesses on at least a part of a surface thereof. In this magnetic powder, it is preferable that when the mean particle size of the magnetic powder is defined by a&mgr;m, the average length of the ridges or recesses is equal to or greater than a/40 &mgr;m. Further, preferably, the ridges or recesses are arranged in roughly parallel with each other so as to have an average pitch of 0.5-100 &mgr;m.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: December 9, 2003
    Assignee: Seiko Epson Corporation
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20030217786
    Abstract: Restoring magnetostriction characteristics without causing fusion of rod. By performing heat treatment on a giant magnetostrictive material within the temperature range of 750 to 860° C., working distortion is removed while bleeding of an R-rich phase on a rod surface is prevented.
    Type: Application
    Filed: February 10, 2003
    Publication date: November 27, 2003
    Applicant: TDK CORPORATION
    Inventors: Teruo Mori, Shiro Tomizawa
  • Publication number: 20030196730
    Abstract: Permanent magnets, devices including permanent magnets and methods for manufacture are described with the permanent magnet comprising, for example: iron-boron-rare earth alloy particulate having an intrinsic coercive force of at least about 1591 kiloamperes/meter (about 20 kiloOersteds) and a residual magnetization of at least about 0.8 tesla (about 8 kiloGauss), wherein the rare earth content comprises praseodymium, a light rare earth element selected from the group consisting of cerium, lanthanum, yttrium and mixtures thereof, and balance neodymium; and a binder bonding the particulate.
    Type: Application
    Filed: May 12, 2003
    Publication date: October 23, 2003
    Inventors: Ralph James Carl, Gerald Burt Kliman, Juliana Chiang Shei, Mark Gilbert Benz, Judson Sloan Marte
  • Publication number: 20030190250
    Abstract: A method for manufacturing a sintered compact includes the steps of preparing an alloy powder having a composition represented by Expression 1: RTW (where, R is at least one kind of rare earth metal, T is at least one kind of transition metal, and w defines a relation of 1<w<4), sintering the alloy powder in a vacuum atmosphere or an atmosphere containing gas with a molecular weight of 30 or less, and processing the alloy powder by a hot isostatic pressing. The sintered compact has a high density, and reduces deteriorations in its sintered compact properties such as magnetostrictive properties in an air atmosphere at high-temperatures.
    Type: Application
    Filed: February 27, 2003
    Publication date: October 9, 2003
    Inventors: Teruo Mori, Takeshi Nomura, Seigo Tokoro, Naomichi Umehara
  • Patent number: 6627313
    Abstract: Spindle-shaped magnetic metal particles containing iron as a main component of the present invention, have an average major axis diameter (L) of 0.05 to 0.15 &mgr;m; a coercive force of 111.4 to 143.2 kA/m; a Co content of from 0.5 to less than 5 atm % based on whole Fe; a crystallite size of from 150 to less than 170 Å; a ratio of Al to Co from 1.0:1 to less than 2.0:1; a specific surface area (S) represented by the formula: S≦−160×L+65; an oxidation stability (&Dgr;&sgr;s) of saturation magnetization of not more than 5.0%; and an ignition temperature of not less than 140° C. The spindle-shaped magnetic metal particles containing iron as a main component, exhibit an adequate coercive force, and are excellent in dispersibility, oxidation stability and coercive force distribution despite fine particles, especially notwithstanding the particles have an average major axis diameter as small as 0.05 to 0.15 &mgr;m.
    Type: Grant
    Filed: October 4, 2001
    Date of Patent: September 30, 2003
    Assignee: Toda Kogyo Corporation
    Inventors: Kenji Okinaka, Masayuki Uegami
  • Publication number: 20030172995
    Abstract: Permanent magnets in which the ferromagnetic phase is matched with the grain boundary phase, and permanent magnets in which magnetocrystalline anisotropy in the vicinity of the outermost shell of the major phase is equivalent in intensity to that in the inside to suppress nucleation of the reverse magnetic domain, more specifically having a magnetocrystalline anisotropy not less than one-half the magnetocrystalline anisotropy of the interiors of the ferromagnetic grains, are disclosed.
    Type: Application
    Filed: September 27, 2002
    Publication date: September 18, 2003
    Applicant: Sumitomo Special Metals Co., Ltd.
    Inventors: Ken Makita, Osamu Yamashita
  • Patent number: 6621398
    Abstract: Disposed in a magnetic gap of a magnetic core, a magnetically biasing permanent magnet is a bond magnet comprising rare-earth magnetic powder and a binder resin. The rare-earth magnetic powder has an intrinsic coercive force of 5 kOe or more, a Curie temperature of 300° C. or more, and an average particle size of 2.0-50 &mgr;m. The rare-earth magnetic power has a surface coated with a metallic layer containing an oxidation-resistant metal. In order to enable a surface-mount to reflow, the rare-earth magnetic powder may have the intrinsic coercive force of 10 kOe or more, the Curie temperature of 500° C. and the average particle size of 2.5-50 &mgr;m. In addition, to prevent specific resistance from degrading, the metallic layer desirably may be coated with a glass layer consisting of low-melting glass having a softening point less than a melting point of the oxidation-resistant metal.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: September 16, 2003
    Assignee: NEC Tokin Corporation
    Inventors: Teruhiko Fujiwara, Masayoshi Ishii, Haruki Hoshi, Keita Isogai, Hatsuo Matsumoto, Toru Ito, Tamiko Ambo
  • Publication number: 20030168129
    Abstract: A magnetic powder for magnetic recording is provided that has improved properties suitable for a magnetic recording medium used with a high-sensitivity read head utilizing an MR device. The magnetic powder is composed of iron-base acicular particles containing Co, Al, R (rare earth elements, including Y) and oxygen within the ranges of Co/Fe=10-50 at. %, dissolved Al/(Fe+Co)=5-50 at. %, R/(Fe+Co)=2-25 at.
    Type: Application
    Filed: March 5, 2003
    Publication date: September 11, 2003
    Inventors: Kazuyuki Matsumoto, Kimitaka Sato, Takatoshi Fujino, Kenichi Inoue
  • Patent number: 6607612
    Abstract: The magnetic alloy includes cobalt (Co), chromium (Cr), and germanium (Ge), the composition of the magnetic alloy being represented by the general formula: CoxCryGez where x, y and z, which represent the composition ratio in terms of atomic %, satisfy the relationships: 78≦x≦87, 2.5≦y≦14.5, 3.5≦z≦15 and x+y+z=100. The magnetic alloy may have a composition represented by the formulas: CoCrGeT (T represents one or more elements of Ta, Si, Nb, B, Ni and Pt) or a composition represented by the formula: CoCrGeT′ (T′ represents one or more elements of Ta, B, and Pt).
    Type: Grant
    Filed: January 8, 2001
    Date of Patent: August 19, 2003
    Assignees: Fuji Electric Co., Ltd., Showa Denko K.K.
    Inventor: Migaku Takahashi
  • Patent number: 6606578
    Abstract: An electromagnetic propulsion fan includes a hub and a plurality of fan blades coupled to the hub. The electromagnetic propulsion fan also includes a rim coupled to the fan blades such that rotating the rim causes the fan blades to rotate. The rim includes a plurality of magnets coupled thereto. The electromagnetic propulsion fan further includes a plurality of electromagnets in proximity to the rim, the electromagnets controllable to generate magnetic fields that interact with the magnetic fields of the magnets to cause the rim to rotated.
    Type: Grant
    Filed: March 1, 2001
    Date of Patent: August 12, 2003
    Assignee: Lockheed Martin Corporation
    Inventors: J. Kirston Henderson, Boyd B. Bushman
  • Publication number: 20030143100
    Abstract: In a process for handling green compacts made from a rare earth metal-based magnetic alloy powder by a press machine to slide, on a sintering support plate, the green compacts, the support plate used has a surface roughness degree Ra in a range of 0.6 to 47 &mgr;m. At a first step, the green compacts are disposed in a first position near a final transport position, and at a second step, the said green compacts disposed in the first position are slid on the sintering support plate and disposed in the final transport position. Thus, by using the support plate having a surface roughness degree in a particular range, the green compacts made from the rare earth metal-based magnetic alloy powder can be sintered without occurrence of the deposition of the green compacts to the support plate, the chipping of the green compacts and the like. In addition, the efficiency of operation of the press machine can be increased.
    Type: Application
    Filed: February 4, 2003
    Publication date: July 31, 2003
    Applicant: SUMITOMO SPECIAL METALS CO., LTD.
    Inventors: Shuhei Okumura, Hiroshi Hashikawa
  • Patent number: 6592682
    Abstract: The invention concerns a method for preparing a magnetic material by forging, characterised in that, in a first embodiment, it comprises the following steps; placing in a sheath an alloy based on at least one rare earth, at least one transition metal and at least one other element selected among boron and carbon; bringing the whole alloy to a temperature not less than 500° C.; forging the whole at a deformation speed of the material not less than 8 s−1. After forging, it is possible to subject the resulting product to at least one annealing and hydridation then dehydridation, in another embodiment, it consists in starting with an alloy based on at least one rare earth and one transition metal and proceeding as in the first embodiment. After forging and, optionally, annealing, hydridation and dehydridation treatments, the resulting material is subjected to nitriding.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: July 15, 2003
    Assignee: Santoku Corporation
    Inventors: Daniel Fruchart, Rene Perrier De La Bâthie, Sophie Rivoirard, Patricia Rango
  • Patent number: RE40348
    Abstract: A thin arc segment magnet made of a an R-T-B based, rare earth sintered magnet substantially comprising 28-33 weight % of R and 0.8-1.5 weight % of B, the balance being substantially Fe T, wherein R is at least one rare earth element including Y, and T is Fe or Fe and Co, which has an oxygen content of 0.3 weight % or less, a density of 7.56 g/cm3 or more, a coercivity iHc of 1.1 MA/m (14 kOe) or more at room temperature, and an orientation Br/4?Imax of 96% or more in an anisotropy-providing direction at room temperature can be produced by using a slurry mixture formed by introducing fine alloy powder of the above composition into a mixture liquid comprising 99.7-99.99 parts by weight of a mineral oil, a synthetic oil or a vegetable oil and 0.01-0.3 parts by weight of a nonionic surfactant and/or an anionic surfactant.
    Type: Grant
    Filed: November 5, 2003
    Date of Patent: June 3, 2008
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hisato Tokoro, Kimio Uchida, Kazuo Oda, Tsukasa Mikamoto