Magnetic Patents (Class 148/300)
  • Publication number: 20040173287
    Abstract: High-permeability, low-core-loss soft magnetic composite materials, compositions containing the same, and methods for making the same are described. These magnetic materials are made by forming fiber or flake shaped particles from a ferromagnetic material, annealing the particles, and then coating an insulating material on the particles. These particles can then be compacted to form an article that has high permeability, high saturation, low core loss, and is a suitable replacement for laminations in various applications, such as motors.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 9, 2004
    Applicant: General Electric Company
    Inventors: Luana Emiliana Iorio, Paul Alfred Siemers, Gerald Burt Kliman, K. Anand, Amitabh Verma
  • Publication number: 20040142198
    Abstract: A kinetically sprayed magnetostrictive/magnetic material, comprising: magnetostriction particles; magnetic particles with coercivity; a ductile matrix for bonding the magnetostriction particles and magnetic particles with coercivity together; wherein an applied magnetic field will align the magnetic particles with coercivity and subsequently the magnetostriction particles such that the magnetostrictive material will produce a detectable change in the magnetostrictive/magnetic material when placed under an applied stress.
    Type: Application
    Filed: January 21, 2003
    Publication date: July 22, 2004
    Inventor: Thomas Hubert Van Steenkiste
  • Publication number: 20040112472
    Abstract: A surface treated magnetic pigment particle suitable for use with a binder in an information-recording layer of magnetic recording media. The surface treated magnetic pigment particle is a magnetic pigment particle with at least first and second surface treatment agents adsorbed onto the surface of the magnetic pigment particle. The first surface treatment agent has the formula E—X1—A1 wherein E is an electron withdrawing group which is not reactive with the binder, A1 is an acidic group, and X1 is a divalent moiety. The second surface treatment agent has the formula F—X2—A2 wherein F is a functional group reactive with the binder, A2 is an acidic group, and X2 is a divalent C1-4 alkyl moiety.
    Type: Application
    Filed: December 17, 2002
    Publication date: June 17, 2004
    Applicant: Imation Corp.
    Inventors: Cheri X. Pereira, Andrei Potanin
  • Patent number: 6747559
    Abstract: A magnetic marker for use in an article surveillance system, and an electronic article surveillance system utilizing the same are presented. The marker comprises a magnetic element including a predetermined number of microwire pieces made of an amorphous metal-containing material coated with glass and having substantially zero magnetostriction, coercivity substantially less than 10 A/m, and permeability substantially higher than 20000, the predetermined number of the microwire pieces and a core diameter of the microwire piece being selected in accordance with a desired detection probability of the marker to be obtained in a specific detection system.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: June 8, 2004
    Assignee: Advanced Coding Systems Ltd.
    Inventors: Alexandru Antonenco, Edward Brook-Levinson, Vladimir Manov, Evgeni Sorkine, Yuri Tarakanov
  • Patent number: 6723179
    Abstract: A soft magnetism metal powder having a majority of particles, each of which, when cross-sectioned, has no greater than ten crystal particles on average, may be coated on an outer surface of each of the particles with a resistive material having a higher resistivity than the underlying parent phase. The soft magnetism metal powder may be prepared by heating a soft magnetism metal powder to a high temperature in a high temperature atmosphere, thereby reducing the number of crystal particles in each of the soft magnetism metal powder particles. A soft magnetism metal formed body may be prepared by pressing the soft magnetism metal particles at a sufficient temperature and pressure.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: April 20, 2004
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Wataru Yagi, Kota Maruyama, Yoshiharu Iyoda, Aiko Nakashima, Toshihisa Terazawa, Naoki Kamiya
  • Publication number: 20030221750
    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 (−&Dgr;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: Application
    Filed: April 14, 2003
    Publication date: December 4, 2003
    Inventors: Alexandra O. Pecharsky, Karl A. Gschneidner, Vitalij K. Pecharsky
  • Publication number: 20030217788
    Abstract: Disclosed herein is a cooling roll which can provide bonded a magnet having excellent magnetic properties and having excellent reliability. A melt spinning apparatus 1 is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and a cooling roll 5 having a circumferential surface 53 in which gas expelling grooves 54 are formed. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 6 so as to be collided with the circumferential surface 53 of the cooling roll 5, so that the molten alloy 6 is cooled and then solidified. In this process, gas is likely to enter between a puddle 7 of the molten alloy 6 and the circumferential surface 53, but such gas is expelled by means of the gas expelling grooves 54.
    Type: Application
    Filed: March 7, 2003
    Publication date: November 27, 2003
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20030213532
    Abstract: A method of manufacturing magnetic powder is disclosed. This method can provide magnetic powder from which a bonded magnet having excellent magnetic properties and reliability can be manufactured. A melt spinning apparatus 1 is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and a cooling roll 5. The cooling roll 5 is constructed from a roll base 51 and a circumferential surface 53 in which gas flow passages 54 for expelling gas are formed. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 3 so as to be collided with the circumferential surface 53 of the cooling roll 5, so that the molten alloy 6 is cooled and then solidified. In this process, gas is likely to enter between a puddle 7 of the molten alloy 6 and the circumferential surface 53, but such gas is expelled by means of the gas flow passages 54. The magnetic powder is obtained by milling thus formed melt spun ribbon 8.
    Type: Application
    Filed: February 25, 2003
    Publication date: November 20, 2003
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20030215351
    Abstract: A new jewelry component alloy and articles of jewelry formed therefrom wherein the components and articles include precious metal alloys of platinum and cobalt that have magnetic properties and high hardnesses so that the various forms of fine jewelry that possess new and unusual visual and functional properties. When these alloys are formed into jewelry articles or components, the magnetic properties enable the components to either be attracted to or repelled by other components of different or like polarities. The jewelry designer is thus able to create pieces with levitating or suspended components, or to make magnetically connected components. The high hardness imparts exceptional durability to these components.
    Type: Application
    Filed: May 9, 2003
    Publication date: November 20, 2003
    Inventor: Steven Kretchmer
  • Publication number: 20030205353
    Abstract: A soft magnetic alloy fiber has a width of 10 &mgr;m or more to less than 500 &mgr;m, a thickness of 2 &mgr;m or more to less than 20 &mgr;m, and a Curie temperature of −50° C. or higher.
    Type: Application
    Filed: May 29, 2003
    Publication date: November 6, 2003
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Takao Sawa, Katsutoshi Nakagawa, Hisashi Takahashi, Teruo Murakami, Masao Obama
  • Publication number: 20030190498
    Abstract: An object of the present invention is to provide an electromagnetic wave absorber which is excellent in the electromagnetic wave absorbing characteristics in the high frequency range above 1 GHz, and to provide a method of manufacturing the electromagnetic wave absorber and appliances using the electromagnetic wave absorber.
    Type: Application
    Filed: April 9, 2001
    Publication date: October 9, 2003
    Inventors: Tadashi Fujieda, Shinzou Ikeda, Sai Ogawa, Teruyoshi Abe, Yasuhisa Aono
  • 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
  • Patent number: 6610421
    Abstract: A spin electronic material exhibiting a spin-dependent electronic effect includes zincblende TE-VE, where TE stands for V, Cr or Mn and VE stands for As or Sb.
    Type: Grant
    Filed: September 7, 2001
    Date of Patent: August 26, 2003
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Hiroyuki Akinaga, Masafumi Shirai, Takashi Manago
  • Patent number: 6599375
    Abstract: A composite magnetic body 1, comprising a soft magnetic powder (2) and a binding agent (3), in which the specific surface area of the soft magnetic powder (2) is 0.1-3 m2/g. The surface state of the soft magnetic powder contained in the composite magnetic body is defined in terms of specific surface area, and self-extinguishing properties, i.e. fire resistance properties, are obtained. An electromagnetic interference suppressing body is obtained using this composite magnetic body.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: July 29, 2003
    Assignee: NEC Tokin Corporation
    Inventor: Yoshio Awakura
  • Patent number: 6596101
    Abstract: Preferred embodiments of the invention provide new nanostructured materials and methods for preparing nanostructured materials having increased tensile strength and ductility, increased hardness, and very fine grain sizes making such materials useful for a variety of applications such as rotors, electric generators, magnetic bearings, aerospace and many other structural and nonstructural applications. The preferred nanostructured materials have a tensile yield strength from at least about 1.9 to about 2.3 GPa and a tensile ductility from at least 1%. Preferred embodiments of the invention also provide a method of making a nanostructured material comprising melting a metallic material, solidifying the material, deforming the material, forming a plurality of dislocation cell structures, annealing the deformed material at a temperature from about 0.30 to about 0.70 of its absolute melting temperature, and cooling the material.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: July 22, 2003
    Assignee: Johns Hopkins University
    Inventors: Timothy P. Weihs, Robert Cammarata, Chia-Ling Chien, Changhe Shang
  • Patent number: 6590485
    Abstract: A magnetic core having excellent DC superposition characteristics and core-loss characteristics is provided. The magnetic core comprises a magnetically biasing magnet disposed in a magnetic gap thereof to provide a magnetic bias from opposite ends of the magnetic gap to the core. The said magnetically biasing magnet comprises a bond magnet which comprises 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 Tc of 300° C. or more, specific resistance of 0.1 &OHgr;·cm or more, residual magnetization Br of 1000 to 4000 G and coercive force bHc of a B-H curve of 0.9 kOe or more.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: July 8, 2003
    Assignee: NEC Tokin Corporation
    Inventors: Teruhiko Fujiwara, Masayoshi Ishii, Haruki Hoshi, Keita Isogai, Toru Ito, Tamiko Ambo
  • Patent number: 6577237
    Abstract: A uni-directional tag for use with position and orientation detection systems, which is not affected by exposure to high magnetic field levels. The tag is constructed from special geometry of magnetic materials and is applicable for example to catheter location systems.
    Type: Grant
    Filed: August 21, 2000
    Date of Patent: June 10, 2003
    Inventor: Andrew Nicholas Dames
  • Patent number: 6556139
    Abstract: A magnetic microwire for use in a magnetic tag attachable to a product is provided to enable authentication of the product, as well as the magnetic tag, a detector device and a system for product authentication utilizing the same. The magnetic microwire is a glass-coated amorphous magnetic microwire characterized by a large Barkhausen discontinuity and substantially zero or positive magnetostriction. The microwire is responsive to an external alternating magnetic field generated by the detector device to produce short pulses of magnetic field perturbations.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: April 29, 2003
    Assignee: Advanced Coding Systems Ltd.
    Inventors: Vladimir Manov, Evgeni Sorkine, Eli Yarkoni
  • Publication number: 20030075243
    Abstract: A method of forming a shimming body for a NMR assembly is provided. A magnetizable metal powder of known magnetic properties is provided. The powder is uniformly dispersed into a non-magnetic material to form a mixture having a selected uniform density. A selected weight of magnetic material is determined for a particular installation of an NMR assembly. The mixture is heated. A selected volume corresponding to the selected weight of magnetic material is extruded into a container. The mixture is cooled to form a shimming body.
    Type: Application
    Filed: January 7, 2002
    Publication date: April 24, 2003
    Inventors: Gregory F. Hayworth, Delton A. Grey, Granville G. Ward
  • Publication number: 20030056858
    Abstract: A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.
    Type: Application
    Filed: October 28, 2002
    Publication date: March 27, 2003
    Inventors: Amit Goyal, Robert K. Williams, Donald M. Kroeger
  • Publication number: 20030056857
    Abstract: A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.
    Type: Application
    Filed: October 28, 2002
    Publication date: March 27, 2003
    Inventors: Amit Goval, Robert K. Williams, Donald M. Kroeger
  • Publication number: 20030056933
    Abstract: A magnet material having excellent magnetic properties and a bonded magnet formed of the magnet material as well as a method of manufacturing the magnet material are disclosed. The method of manufacturing the magnet material is carried out by discharging a molten metal of the magnet material from a nozzle while rotating a cooling roll having a surface layer composed of ceramics on its outer periphery to be collided with the surface layer of the cooling roll and solidified by cooling, the method of manufacturing the magnet material being characterized in that the time during which the magnet material is in contact with the surface layer of the cooling roll is not less than 0.5 ms when the molten metal of said magnet material is discharged from directly above the center of rotation of the cooling roll toward an apex part of the cooling roll to be collided with the apex part.
    Type: Application
    Filed: April 25, 2002
    Publication date: March 27, 2003
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20030037844
    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: Application
    Filed: September 12, 2002
    Publication date: February 27, 2003
    Inventors: Marlin S. Walmer, Joanne H. Walmer, Christina H. Chen, Shiqiang Liu, Michael H. Walmer, G. Edward Kuhl
  • Publication number: 20030034091
    Abstract: An iron alloy strip having a gage of 0.1 to 5 mm and a magnetic field strength variation within the strip of 0 to 10 Hz, made of an iron alloy consisting essentially of, in % by weight, 0.0001-0.02% of C, 0.0001-5% of Si, 0.001-0.2% of Mn, 0.0001-0.05% of P, 0.0001-0.05% of S, 0.0001-5% of Al, 0.001-0.1% of O, 0.0001-0.03% of N, 0-10% of Co, 0-10% of Cr, 0.01-5% in total of Ti, Zr, Nb, Mo, V, Ni, W, Ta and/or B, and the balance of Fe, and having a saturation magnetic flux density of 1.7-2.3 Tesla, a maximum relative permeability of 1,200-22,000 and a coercive force of 20-380 A/m is suited for use as yokes in voice coil motor magnetic circuits. The iron alloy strip is highly resistant to corrosion and eliminates a need for a corrosion resistant coating.
    Type: Application
    Filed: August 7, 2002
    Publication date: February 20, 2003
    Inventors: Masanobu Shimao, Masaaki Nishino, Takehisa Minowa
  • Publication number: 20030024605
    Abstract: A magnetic substance having the maximum value of complex permeability in quasi-microwave range is provided for suppressing a high frequency noise in a small-sized (electronic apparatus. The magnetic substance is of a magnetic composition comprising M, X and Y, where M is a metallic magnetic material consisting of Fe, Co, and/or Ni, X being element or elements other than M and Y, and Y being F, N, and/or O. The M-X-Y magnetic composition has a concentration of M in the composition so that said M-X-Y magnetic composition has a saturation magnetization of 35-80% of that of the metallic bulk of magnetic material comprising M alone. The magnetic composition has the maximum &mgr;″max of complex.
    Type: Application
    Filed: September 4, 2001
    Publication date: February 6, 2003
    Inventors: Shigeyoshi Yoshida, Hiroshi Ono, Shinsuke Andoh, Wei-Dong Li, Yutaka Shimada
  • Patent number: 6514358
    Abstract: Magnetic materials for use in sputtering targets are hot rolled and stretched at ambient temperature or at a temperature not exceeding 1400° F. The magnetic material can be pure Co, pure Ni, or Co based alloys.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: February 4, 2003
    Assignee: Heraeus, Inc.
    Inventors: Michael Bartholomeusz, Michael Tsai
  • Publication number: 20020189715
    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: Application
    Filed: April 24, 2002
    Publication date: December 19, 2002
    Inventors: Kenji Okinaka, Kohji Mori, Masayuki Uegami
  • Publication number: 20020162605
    Abstract: MRI-compatible medical instruments and appliances are made using bulk metallic glass alloys. MRI-guided methods include the use of articles that include bulk metallic glass alloys.
    Type: Application
    Filed: March 5, 2001
    Publication date: November 7, 2002
    Inventors: Joseph A. Horton, Douglas E. Parsell
  • Patent number: 6472037
    Abstract: A non-permanent adhesive-backed magnetized securing device allows for affixing and removing objects from the adhesive portion of the device with minimal to no destruction or marring of the contacted surface of the object. The device includes a base member and a non-permanent adhesive connected to the base member. The base member has a surface that exhibits magnetic characteristics and is capable of magnetically connecting the device to a magnetic attracting element. The non-permanent adhesive is permanently affixed to another surface of the base member and is capable of allowing objects to be removably attached to the device. A dividing member may be located between the base member and the non-permanent adhesive. A permanent adhesive fixedly connects the dividing member to the base member.
    Type: Grant
    Filed: July 8, 1999
    Date of Patent: October 29, 2002
    Assignee: Kane Graphical Corporation
    Inventor: Jonathan E. Kane
  • Publication number: 20020153066
    Abstract: The present invention offers a minute-sized magnet with superior magnetic energy product (BH)max and coercivity iHc, as well as superior anti-corrosive properties. This magnet is comprised of an alloy comprised of 35-55 atomic % platinum, 0.0 01-10 atomic % third element, which is one or more elements from groups IVa, Va, IIIb, or IVb, and a remainder of iron and other unavoidable impurities. The average crystal size of this FePt alloy is 0.3 &mgr;m. By mixing an FePt alloy with a specific element in a designated ratio, an FePt magnet with more excellent characteristics than ones made from previous alloys was successfully made.
    Type: Application
    Filed: March 4, 2002
    Publication date: October 24, 2002
    Applicant: AICHI STEEL CORPORATION
    Inventors: Hitoshi Aoyama, Yoshinobu Honkura, Takumi Asano
  • Patent number: 6425960
    Abstract: A soft magnetic alloy strip is manufactured by a single roll method. The soft magnetic alloy strip is 0.2×d mm or less (, which “d” is a width of the strip,) in warpage in the widthwise direction of the strip, and has a continuous, long length not less than 50 m, in which a width of an air pockets occurring on a roll contact face is not more than 35 &mgr;m, a length of the air pockets is not more than 150 &mgr;m, and the centerline average roughness Ra of the roll contact face is not more than 0.5 &mgr;m.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: July 30, 2002
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yoshihito Yoshizawa, Yoshio Bizen, Shunsuke Arakawa, Michihiro Nagao, Takashi Meguro
  • Patent number: 6423386
    Abstract: The magnet powder-resin compound particles substantially composed of rare earth magnet powder and a binder resin are in such a round shape that a ratio of the longitudinal size a to the transverse size b (a/b) is more than 1.00 and 3 or less, and that an average particle size defined by (a/b)/2 is 50-300 &mgr;m. They are produced by charging a mixture of rare earth magnet powder and a binder resin into an extruder equipped with nozzle orifices each having a diameter of 300 &mgr;m or less; extruding the mixture while blending under pressure though the nozzle orifices to form substantially cylindrical, fine pellets; and rounding the pellets by rotation.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: July 23, 2002
    Assignee: Hitachi Metals, Ltd.
    Inventors: Katsunori Iwasaki, Kazunori Tabaru
  • Publication number: 20020066498
    Abstract: A method of manufacturing magnetic powder is disclosed. This method can provide magnetic powder from which a bonded magnet having excellent magnetic properties and reliability can be manufactured. A melt spinning apparatus 1 is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and a cooling roll 5. The cooling roll 5 is constructed from a roll base 51 and a circumferential surface 53 in which gas flow passages 54 for expelling gas are formed. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 3 so as to be collided with the circumferential surface 53 of the cooling roll 5, so that the molten alloy 6 is cooled and then solidified. In this process, gas is likely to enter between a puddle 7 of the molten alloy 6 and the circumferential surface 53, but such gas is expelled by means of the gas flow passages 54. The magnetic powder is obtained by milling thus formed melt spun ribbon 8.
    Type: Application
    Filed: July 31, 2001
    Publication date: June 6, 2002
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20020055009
    Abstract: The present invention relates to a magnetic device and method for making it, wherein the magnetic device is specifically constructed of grains in a matrix. The matrix may be cement or plaster. The grains have an average diameter that is greater than their magnetic domains. The device may be applied to shielding applications for frequencies ranging from 100 kHz to 10 GHz. The shielding may be applied to walls of a building, consumer products such as magnetic disks, and the like. The grains may be any ferromagnetic material, including ferrite.
    Type: Application
    Filed: January 10, 2002
    Publication date: May 9, 2002
    Inventors: Mauricio Esguerra, Ralph Lucke
  • Publication number: 20020053372
    Abstract: A magnetic material manufacturing method, a ribbon-shaped magnetic material manufactured by the method, a powdered magnetic material formed from the ribbon-shaped magnetic material and a bonded magnet manufactured using the powdered magnet material are disclosed. The method and the magnetic materials can provide magnets having excellent magnetic properties and reliability. A melt spinning apparatus 1 is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and a cooling roll 5 having a circumferential surface 53 on which dimple correcting means is provided. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 3 so as to be collided with the circumferential surface 53 of the cooling roll 5 in an inert gas atmosphere (ambient gas) such as helium gas, so that the molten alloy 6 is cooled and then solidified.
    Type: Application
    Filed: May 30, 2001
    Publication date: May 9, 2002
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20020020472
    Abstract: Disclosed herein is a cooling roll which can provide bonded a magnet having excellent magnetic properties and having excellent reliability. A melt spinning apparatus 1 is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and a cooling roll 5 having a circumferential surface 53 in which gas expelling grooves 54 are formed. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 6 so as to be collided with the circumferential surface 53 of the cooling roll 5, so that the molten alloy 6 is cooled and then solidified. In this process, gas is likely to enter between a puddle 7 of the molten alloy 6 and the circumferential surface 53, but such gas is expelled by means of the gas expelling grooves 54.
    Type: Application
    Filed: April 12, 2001
    Publication date: February 21, 2002
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20020020514
    Abstract: Disclosed herein is a method of manufacturing a magnetic material which can provide a bonded magnet having excellent magnetic properties and having excellent reliability. A melt spinning apparatus 1 is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and a cooling roll 5 having a circumferential surface 53 in which gas expelling grooves 54 are formed. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 6 so as to be collided with the circumferential surface 53 of the cooling roll 5, so that the molten alloy 6 is cooled and then solidified. In this process, gas is likely to enter between a puddle 7 of the molten alloy 6 and the circumferential surface 53, but such gas is expelled by means of the gas expelling grooves 54.
    Type: Application
    Filed: April 12, 2001
    Publication date: February 21, 2002
    Inventors: Akira Arai, Hiroshi Kato
  • Publication number: 20020014181
    Abstract: A ferromagnetic powder comprising ferromagnetic particles coated with a material that does not degrade at temperatures above 150° C. and permits adjacent particles to strongly bind together after compaction such that parts made from the ferromagnetic powder have a transverse rupture strength of about 8,000 to about 20,000 pounds/square inch before sintering. The coating includes from 2 to 4 parts of an oxide and one part of a chromate, molybdate, oxalate, phosphate, or tungstate. The coating may be substantially free of organic materials. The invention also includes a method of making the ferromagnetic powder, a method of making soft magnetic parts from the ferromagnetic powder, and soft magnetic parts made from the ferromagnetic powder.
    Type: Application
    Filed: October 30, 1998
    Publication date: February 7, 2002
    Inventors: DAVID S. LASHMORE, GLENN L. BEANE, LEV DERESH, ZONGLU HUA
  • Publication number: 20020003383
    Abstract: The present invention pertains to methods for altering the magnetic properties of materials and the novel materials produced by these methods. The methods of this invention concern the application of high voltage, high frequency sparks to the surface of materials in order to alter the magnetic properties of the materials. Specially, the present invention can be applied to diamagnetic silicon to produce ferromagnetic spark-processed silicon.
    Type: Application
    Filed: June 1, 2001
    Publication date: January 10, 2002
    Inventors: Jonathan A. Hack, Rolf E. Hummel, Matthias H. Ludwig
  • Publication number: 20010038325
    Abstract: Composite media having simultaneous negative effective permittivity and permeability over a common band of frequencies. A composite media of the invention combines media, which are either themselves separately composite or continuous media, having a negative permittivity and a negative permeability over a common frequency band. Various forms of separate composite and continuous media may be relied upon in the invention. A preferred composite media includes a periodic array of conducting elements that can behave as an effective medium for electromagnetic scattering when the wavelength is much longer than both the element dimension and lattice spacing The composite media has an effective permittivity &egr;eff(&ohgr;) and permeability &mgr;eff(&ohgr;) which are simultaneously negative over a common set of frequencies. Either one or both of the negative permeability and negative permittivity media used in the invention may be modulable via external or internal stimulus.
    Type: Application
    Filed: March 16, 2001
    Publication date: November 8, 2001
    Applicant: The Regents of the Uinversity of California
    Inventors: David Smith, Sheldon Schultz, Norman Kroll, Richard A. Shelby
  • Patent number: 6284060
    Abstract: A magnetic core of a compressed compact comprises a mixture of magnetic powder and a spacing material, wherein the distance between adjacent magnetic powder particles is controlled by the spacing material. In this constitution, a magnetic core low in core loss, high in magnetic permeability, and excellent in direct-current superposing characteristic is realized.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: September 4, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobuya Matsutani, Yuji Mido
  • Publication number: 20010015239
    Abstract: The method for producing iron-base alloy permanent magnet powder of the present invention includes the steps of: chilling an Fe—R—B molten alloy by melt quenching, thereby forming a rapidly solidified alloy having a thickness in a range of 80 &mgr;m to 300 &mgr;m; crystallizing the rapidly solidified alloy by heat treatment, thereby producing an alloy having permanent magnet properties; and pulverizing the alloy to produce powder having an average particle size in a range of 50 &mgr;m to 300 &mgr;m or less and a ratio of minor axis size to major axis size of powder particles in a range of 0.3 to 1.0.
    Type: Application
    Filed: December 13, 2000
    Publication date: August 23, 2001
    Inventor: Hirokazu Kanekiyo
  • Patent number: 6270591
    Abstract: The invention refers to amorphous and nanocrystalline magnetic glass-covered wires. The wires consist of a metallic amorphous or nanocrystalline core with diameters by the order of 10−6 m, having compositions based on transition metal-metalloids and other additional metals and a glass cover, having a thickness of the wall by the same order of magnitude. The wires present high or medium saturation inducation, positive, negative or nearly zero magnetostriction and values of the coercive field and of the magnetic permeability in function of the requested applications in a field of electronics and electrotechnics to achieve sensors, transducers, inductive coils, trnasformers, magnetic shields, devices working on the basis of the correlation between the magnetic properties of the metallic core and the optical properties of the glass cover.
    Type: Grant
    Filed: June 25, 1998
    Date of Patent: August 7, 2001
    Inventors: Horia Chiriac, Firuta Barariu, Adrian Tibor Ovari, Gheorghe Pop
  • Patent number: 6143096
    Abstract: A powdery alloy mainly composed of Mn--Bi having particle diameter of 5 .mu.m or less which has a magnetic anisotropy of 6000 Oe or more in coercive force and 35 emu/g or more in saturation magnetization, wherein the size of crystallite according to Scheler's formula is 700 .ANG. or less; and an alloy containing sheet of 0.5 to 10 .mu.m thickness in which a powdery alloy mainly composed of Mn--Bi having particle diameter of 5 .mu.m or less which has a magnetic anisotropy of 6000 Oe or more in coercive force and 35 emu/g or more in saturation magnetization is bound with a binder into a sheet of 0.5 to 10 .mu.m thickness in a state magnetically oriented toward said direction of magnetic anisotropy, wherein when said sheet is measured toward said magnetic anisotropy direction at 16 kOe and 5 kOe, the ratio of residual magnetic flux density Mr16k and Mr5k (Mr5k/Mr16k) is 0.85 or more.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: November 7, 2000
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Shinichi Kitahata, Hisao Kanzaki
  • Patent number: 6132524
    Abstract: A semiconductor magneto-optical material includes a semiconductor dispersed with fine magnetic material particles and is characterized by exhibiting magneto-optical effect at ordinary room temperature.
    Type: Grant
    Filed: January 15, 1998
    Date of Patent: October 17, 2000
    Assignees: Agency of Industrial Science & Technology, Ministry of International Trade & Industry, Tokin Corporation
    Inventors: Hiroyuki Akinaga, Koichi Onodera
  • Patent number: 6117205
    Abstract: Corrosion-resistant, soft magnetic metal components manufactured by powder metallurgy and infiltration processes are disclosed. The magnetic components are manufactured by a powder metallurgy process using acicular metal particles to form a skeleton, and thermally infiltrating the skeleton.
    Type: Grant
    Filed: November 20, 1998
    Date of Patent: September 12, 2000
    Assignee: Magnetics International, Inc.
    Inventors: Robert F. Krause, Harold R. Kokal, Joseph H. Bularzik
  • Patent number: 6103396
    Abstract: An amorphous metal strip having a sheet thickness ranging from about 50 to 75 .mu.m and a sheet width of at least 20 mm is produced by a casting process utilizing a single nozzle orifice and a high thermal conductivity, large diameter wheel as a casting substrate. The strip has a fracture strain of 0.01 or more, a lamination factor of 0.8 or more, and a core loss of less than 0.2 W/kg at 60 Hz and 1.4 T.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: August 15, 2000
    Assignee: AlliedSignal Inc.
    Inventors: Santosh K. Das, Richard L. Bye, Jeng S. Lin
  • Patent number: 6063209
    Abstract: A magnetic core of a compressed compact comprises a mixture of magnetic powder and a spacing material, wherein the distance between adjacent magnetic powder particles is controlled by the spacing material. In this constitution, a magnetic core low in core loss, high in magnetic permeability, and excellent in direct-current superposing characteristic is realized.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: May 16, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobuya Matsutani, Yuji Mido
  • Patent number: 6033792
    Abstract: A recording head for recording data onto a recording medium is provided with a thin film formed of the following compound Fe.sub.100-a-b-c X.sub.a Y.sub.b Z.sub.c, wherein X is at least one element selected from the group consisting of Nb, Ta, Hf and Zr, Y is one or two elements selected from the group consisting of Cr, Ru, Al, Si, Ti and Rh, and Z is at least one element selected from the group consisting of C and N, and wherein 5.ltoreq.a.ltoreq.20, 0.5.ltoreq.b.ltoreq.15, 1.ltoreq.c.ltoreq.20, and 0.5.ltoreq.a/c.ltoreq.0.7, the carbide or the nitride of the element X having an average grain size of not larger than 3 nm. This way, increased corrosion resistance is provided without substantially reducing magnetic characteristics such as saturation and coercive force. A recording apparatus, such as a VTR, including such a recording head is disclosed as well as a recording medium formed using this thin film.
    Type: Grant
    Filed: October 19, 1998
    Date of Patent: March 7, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Fumiyoshi Kirino, Shigekazu Otomo, Nagatugu Koiso, Noriyuki Kumasaka, Takeshi Miura