Silicon Containing Patents (Class 148/307)
  • Publication number: 20030183304
    Abstract: A high flux density grain-oriented electrical steel sheet excellent in high magnetic field core loss property containing, in percentage by weight, not greater than 0.005% of C, 2.0-7.0% of Si, not greater than 0.2% of Mn, one or both of S and Se in a total amount of not greater than 0.005%, the balance being of Fe and unavoidable impurities, optionally containing, in percentage by weight, of not greater than 0.065% of Al, not greater than 0.005% of N and 0.003-0.3% each of one or more of Sb, Sn, Cu, Mo, Ge, B, Te, As, Cr and Bi, the steel sheet having a grain orientation deviating from an ideal {110}<001>orientation by an average of not greater than 5°, having an average 180° magnetic domain width of not greater than 0.30 mm, preferably not greater than 0.26 mm or greater than 0.26 mm and not greater than 0.30 mm, and having an area ratio of magnetic domains of a width greater than 0.4 mm of greater than 3% and not greater than 20%.
    Type: Application
    Filed: March 28, 2003
    Publication date: October 2, 2003
    Applicant: Nippon Steel Corporation
    Inventors: Yousuke Kurosaki, Masahiro Fujikura
  • Patent number: 6627005
    Abstract: A steel wire of pearlite structure containing 0.8-1.0 mass % of C and 0.8-1.5 mass % of Si is disclosed. In the cross section of the steel wire the average hardness in a region up to 100 &mgr;m from the surface thereof is at least 50 higher that that in a deeper region based on micro-Vickers hardness. The steel wire is manufactured by working a wire rod having the abovementioned chemical composition through shaving, patenting and drawing processes, then strain-relief annealing the resultant wire, and thereafter subjecting the thus annealed wire to a short peening process. The steel wire can be produced through a drawing process without applying a quenching and tempering process, and are superior in heat resistance and fatigue strength.
    Type: Grant
    Filed: May 1, 2000
    Date of Patent: September 30, 2003
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Nozomu Kawabe, Teruyuki Murai
  • Publication number: 20030177867
    Abstract: The invention concerns a process permitting the preparation of a new powder, which as such or further processed is useful within a wide variety of different fields and which has magnetic and electric properties. The powder includes at least 0.5% by weight of iron containing silicate and at least 10% by weight of metallic iron and/or alloyed iron and is prepared by a process comprising the steps of mixing an iron containing powder and a silicon containing powder; and reducing the obtained mixture at a temperature above about 450° C.
    Type: Application
    Filed: November 25, 2002
    Publication date: September 25, 2003
    Inventors: Lars Hultman, Nils Jonsson, Britt Benemark, Peter Grahn, Svante Grahn
  • Patent number: 6599468
    Abstract: The present invention provides a powder compacting apparatus including: a die having a through hole forming a cavity; a first punch and a second punch for pressing a rare-earth alloy magnetic powder filled in the cavity; and a magnetic field generator for applying an orientation magnetic field parallel to a pressing direction through the rare-earth alloy magnetic powder in the cavity, wherein at least one of the first and second punches and has a curved pressing surface, and the pressing surface is given a shape such as to suppress the movement of particles of the rare-earth alloy magnetic powder along the pressing surface during the pressing step.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: July 29, 2003
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Shuichi Okuyama, Tsutomu Harada, Takashi Tajiri
  • Publication number: 20030136467
    Abstract: An object of the present invention is to provide a magnesium oxide particle aggregate having a controlled particle aggregation structure so that the solid phase-solid phase reaction between magnesium oxide and the SiO2 film on the surface can be appropriately controlled. The object can be achieved by a magnesium oxide particle aggregate characterized in that a first inflection point diameter is 0.30×10−6 m or less, an interparticle void volume is 1.40×10−3 to 2.20×10−3 m3/kg and a particle void volume is 0.55×10−3 to 0.80×10−3 m3/kg in a cumulative intrusion volume curve of the particle aggregate.
    Type: Application
    Filed: October 29, 2002
    Publication date: July 24, 2003
    Inventors: Yutaka Hiratsu, Toshio Kiyokawa, Atsuo Toutsuka
  • Publication number: 20030121566
    Abstract: A grain-oriented electromagnetic steel sheet having a multiplicity of fine grains having a diameter of about 3 mm or less on the surface of the steel sheet, in a numerical ratio of about 65% or more and of about 98% or less relative to the constituting grains that penetrate the sheet along the direction parallel to its thickness, and a method for producing the same. The fine grains are artificially created and regularly disposed with a random orientation in the steel sheet, and contribute to decreasing the strain susceptibility of the steel. More preferably, a treatment for finely dividing magnetic domains is applied on the surface of the steel sheet.
    Type: Application
    Filed: June 6, 2002
    Publication date: July 3, 2003
    Applicant: Kawasaki Steel Corporation
    Inventors: Michiro Komatsubara, Toshito Takamiya, Kunihiro Senda
  • Publication number: 20030102055
    Abstract: The object of the present invention is to provide a low iron loss and low noise grain-oriented electrical steel sheet for securing both low core loss and low noise of a transformer at the same time.
    Type: Application
    Filed: November 6, 2002
    Publication date: June 5, 2003
    Applicant: Nippon Steel Corporation
    Inventors: Masahiro Fujikura, Satoshi Arai, Mosato Mizokami, Hisashi Mogi, Takeshi Kubota
  • Patent number: 6569265
    Abstract: A method of making electrical steel strip characterized by low core loss and high permeability in the rolling direction includes the steps of: hot rolling a slab of an electrical steel composition into a strip, hot band annealing in a temperature range effective to coarsen the grains sufficient to improve magnetic properties in a rolling direction of the strip, cold rolling, batch annealing in a temperature range effective to produce a batch annealed grain size of not greater than 40 &mgr;m and, preferably not greater than 20 &mgr;m, and temper rolling to provide the strip with a transfer surface roughness (Ra) of less than 49 &mgr;in. Electrical steel articles are manufactured from the steel strip upon final annealing. The electrical steel articles have a grain texture including a {110}<001> orientation and improved permeability in the rolling direction.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: May 27, 2003
    Assignee: International Steel Group Inc.
    Inventors: Jeffery P. Anderson, Barry A. Lauer
  • Patent number: 6562473
    Abstract: Electrical steel sheets having superior magnetic properties, anti-noise properties, and workability, are ideal for use a compact iron core material in electric apparatuses, such as compact transformers, motors, and electric generators. A totally new electrical steel sheet and a manufacturing method therefor are proposed, in which the electrical steel sheet is not only most advantageous in magnetic properties but also advantageous from economic point of view. That is, the electrical steel sheet of the present invention is composed of from about 2.0 to 8.0 wt % Si, from about 0.005 to 3.0 wt % Mn, from about 0.0010 to 0.020 wt % Al, balance essentially iron. The magnetic flux density B50(L) in a rolling direction and the magnetic flux density B50(C) in the direction perpendicular thereto are 1.70 T or more, and the B50(L)/B50(C) is 1.005 to 1.100.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: May 13, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Seiji Okabe, Yasuyuki Hayakawa, Takeshi Imamura, Mitsumasa Kurosawa
  • Patent number: 6559573
    Abstract: A shaft 2 of a spindle motor is composed of a steel material including 0.20 wt % of C, 0.35 wt % of Si, 8.00 wt % of Mn, higher than 0 and equal to or less than 0.05 wt % of P, 0.15 wt % of S, higher than 0 and equal to or less than 2.00 wt % of Ni and 14.00 wt % of Cr and the remainder substantially being Fe. The steel material has corrosion resistance with no plating requirement and wear resistance with no need for a heat treatment and/or a soft nitriding. Further, when considering a conventionally employed stainless steel, Pb has been frequently added thereto in order to improve machinability. On the contrary, the steel material according to the embodiments of the present invention is Pb-free material. Since the shaft of the spindle motor is manufactured by a material high in its wear resistance, corrosion resistance and workability and in which the generation of the out gas of sulfur and sulfur compounds is suppressed low, the qualities of electronic devices and communication devices, etc.
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: May 6, 2003
    Assignee: Minebea Co., Ltd.
    Inventors: Akio Okamiya, Toshisada Koyama
  • 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
  • Patent number: 6537389
    Abstract: A magnetically soft, moldable composite material include powder grains coated with nonmagnetic thermoplastic compounds or with molecular precursors for ceramics or with intermetallic compounds, the magnetic properties of the magnetically soft composite material being adjustable in that fashion. Also described is a method for manufacturing a magnetically soft, shapable composite material coated in that fashion, which can subsequently be processed into shaped parts.
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: March 25, 2003
    Assignee: Robert Bosch GmbH
    Inventors: Wilfried Aichele, Hans-Peter Koch
  • Patent number: 6531001
    Abstract: Non-oriented magnetic steel sheets, which are mainly used as materials for iron cores for use in electric apparatuses, have a low iron loss and a high magnetic flux density at the same time. The non-oriented magnetic steel sheet comprises from about 1.5 to about 8.0 weight % Si, from about 0.005 to about 2.50 weight % Mn, and not more than about 50 ppm each of C, S, N, O, and B, in which a crystal orientation parameter <&Ggr;> is 0.200 or less. In addition, the average crystal grain diameter is preferably from about 50 to about 500 &mgr;m, and an areal ratio of crystal grains on a surface of the steel sheet is preferably 20% and less, in which crystal plane orientations of the crystal grains are within 15° from the <111> axis. In addition, the non-oriented magnetic steel sheet preferably contains small amounts of elements such as Al, Sb, Ni, Sn, Cu, P, and Cr. The manufacturing method for the non-oriented magnetic steel is also described.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: March 11, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Yasuyuki Hayakawa, Mitsumasa Kurosawa, Masaki Kawano, Michiro Komatsubara, Yuka Komori, Kazuaki Tamura
  • Patent number: 6527876
    Abstract: A silicon steel sheet having low iron loss of high frequency has a surface layer of the steel sheet which has Si concentration higher than Si concentration of a center portion of the steel sheet. Si concentration of sheet thickness center is 3.4 wt. % or more and Si concentration of the surface layer of the steel sheet is 5 wt. % or more. Si concentration in a surface layer portion is 5 to 8 wt. %. The production method comprises siliconizing treatment and diffusing treatment. Velocity of siliconizing and diffusing are controlled, and Si concentration distribution in the sheet thickness direction of the steel sheet is controlled.
    Type: Grant
    Filed: January 24, 2000
    Date of Patent: March 4, 2003
    Assignee: NKK Corporation
    Inventors: Misao Namikawa, Yoshikazu Takada, Shoji Kasai, Hironori Ninomiya, Tsunehiro Yamaji, Tatsuhiko Hiratani
  • Publication number: 20030034092
    Abstract: Manufacturing a grain-oriented electrical steel sheet, a secondary recrystallization step and a forsterite coating forming step are separated into first batch annealing for developing secondary recrystallization and second batch annealing for forming a forsterite coating, with continuous annealing performed between these two steps of batch annealing, to produce a grain-oriented electrical steel sheet that is superior in both magnetic characteristics and coating characteristics.
    Type: Application
    Filed: July 30, 2002
    Publication date: February 20, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Minoru Takashima, Tetsuo Toge, Yasuyuki Hayakawa, Mitsumasa Kurosawa, Michiro Komatsubara
  • Patent number: 6521055
    Abstract: A method of stress inducing transformation from the austenite phase to the martensite phase by conducting cold working on material of austenite stainless steel in the temperature range from the point Ms to the point Md. The above cold working is a biaxial tensing. An intermediately formed hollow body is made, which includes a ferromagnetic portion and a non-magnetic portion contracting inward. Then, the intermediately formed body is subjected to a stress removing process in which residual tensile stress is removed from an intermediately formed body. In the stress removing process, it is preferable that a punch is press-fitted into the intermediately formed body so as to expand a non-magnetic portion and then the intermediately formed body is drawn with ironing while the punch is inserted so that the residual tensile stress can be changed into the residual compressive stress in the non-magnetic portion.
    Type: Grant
    Filed: February 3, 2000
    Date of Patent: February 18, 2003
    Assignee: Denso Corporation
    Inventors: Satoshi Sugiyama, Yoshihiro Tanimura, Masaki Shimizu, Yoshitada Katayama, Hidehito Kito, Suehisa Sugisaka
  • Publication number: 20030024606
    Abstract: Non-oriented magnetic steel sheets, which are mainly used as materials for iron cores for use in electric apparatuses, have a low iron loss and a high magnetic flux density at the same time. The non-oriented magnetic steel sheet comprises from about 1.5 to about 8.0 weight % Si, from about 0.005 to about 2.50 weight % Mn, and not more than about 50 ppm each of C, S, N, O, and B, in which a crystal orientation parameter <&Ggr;> is 0.200 or less. In addition, the average crystal grain diameter is preferably from about 50 to about 500 &mgr;m, and an areal ratio of crystal grains on a surface of the steel sheet is preferably 20% and less, in which crystal plane orientations of the crystal grains are within 15° from the <111> axis. In addition, the non-oriented magnetic steel sheet preferably contains small amounts of elements such as Al, Sb, Ni, Sn, Cu, P, and Cr. The manufacturing method for the non-oriented magnetic steel is also described.
    Type: Application
    Filed: May 8, 2002
    Publication date: February 6, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Yasuyuki Hayakawa, Mitsumasa Kurosawa, Masaki Kawano, Michiro Komatsubara, Yuka Komori, Kazuaki Tamura
  • Publication number: 20030005978
    Abstract: A magnetic circuit member contains a matrix portion including iron and silicon; and graphite particles in the matrix. Each of the graphite particles has either a spherical shape or a compact vermicular shape. The inclusion of graphite particles having a relatively low conductivity in the matrix portion having a good magnetic property prevents eddy currents from forming in the magnetic circuit member in an alternating magnetic field, thus preserving the original magnetic property found in the absence of the alternating magnetic field. Each of the graphite particles has a spherical or compact vermicular shape that does not intercept magnetic flux passing through the material forming the magnetic circuit member. The graphite contained in the material improves liquidity of the melted material in casting, thus the magnetic circuit member can be manufactured by casting.
    Type: Application
    Filed: March 19, 2002
    Publication date: January 9, 2003
    Applicant: AISIN SEIKI KABUSHIKI KAISHA
    Inventors: Akikazu Matsumoto, Wataru Yagi
  • Patent number: 6504737
    Abstract: A magnetic core for use in a saturable reactor made of an Fe-based soft-magnetic alloy comprising as essential alloying elements Fe, Cu and M, wherein M is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo, and having an alloy structure at least 50% in area ratio of which being fine crystalline particles having an average particle size of 100 nm or less. The magnetic core has control magnetizing properties of a residual operating magnetic flux density &Dgr;Bb of 0.12 T or less, a total control operating magnetic flux density &Dgr;Br of 2.0 T or more, and a total control gain Gr of 0.10-0.20 T/(A/m) calculated by the equation: Gr=0.8×(&Dgr;Br−&Dgr;Bb)/Hr, wherein Hr is a total control magnetizing force defined as a control magnetizing force corresponding to 0.8×(&Dgr;Br−&Dgr;Bb)+&Dgr;Bb.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: January 7, 2003
    Assignee: Hitachi Metals, Ltd.
    Inventors: Shin Nakajima, Hirohiko Miki, Sadami Kubota, Mutsuhito Sakaguchi
  • Patent number: 6478892
    Abstract: The present invention provides a non-oriented electrical steel sheet having crystal grains of small diameter and excellent workability before stress relief annealing and having crystal grains of largely grown diameter and excellent iron loss property after stress relief annealing and a method for producing the same, and relates to a low iron loss non-oriented electrical steel sheet excellent in workability, containing, in weight %, 0.010% or less of C, 0.1 to 1.5% of Mn, 0.1 to 4% of Si, 0.1 to 4% of Al, wherein the latter three elements satisfy the formula Si+Mn+Al≦5.0%, and 0.0005 to 0.0200% of Mg, or further containing 0.005% or more of Ca, wherein the total amount of Mg and Ca is 0.0200% or less, or further containing 0.005% or more of REM, wherein the total amount of Mg and REM is 0.0200% or less, or further containing 0.005% or more of Ca and REM, wherein the total amount of Mg, Ca and REM is 0.0200% or less, and containing the remainder consisting of Fe and unavoidable impurities.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: November 12, 2002
    Assignee: Nippon Steel Corporation
    Inventors: Ken-ichi Murakami, Takashi Morohoshi, Tomoji Kumano, Ryutaro Kawamata, Takeshi Kubota, Masafumi Zeze, Hidekuni Murakami, Shinichi Kanao
  • Patent number: 6475304
    Abstract: Grain-oriented silicon steel sheet with Bi as an auxiliary inhibitor and a forsterite coating film having a Cr spinel oxide subscale of FeCr2O4 or FexMn1-xCr2O4 (0.6≦x≦1), made from a steel slab containing 0.005-0.20 wt % of Bi and 0.1-1.0 wt % of Cr.
    Type: Grant
    Filed: July 18, 2001
    Date of Patent: November 5, 2002
    Assignee: Kawasaki Steel Corporation
    Inventors: Hiroaki Toda, Kunihiro Senda, Mitsumasa Kurosawa, Makoto Watanabe, Atsuhito Honda
  • Publication number: 20020157734
    Abstract: A grain oriented electrical steel sheet comprises metal part containing Si: about 2.5 to about 5.0 mass % and Cr: about 0.05 to about 1.0 mass %, and an insulation coating formed on a surface of the metal part. A tension imparted to the metal part in the rolling direction by the insulation coating is not smaller than about 3.0 MPa. Magnetic flux density B8 satisfies a specific relation formula. A plurality of linear strains or grooves are formed in a surface of the steel sheet and linearly extended at an angle of not larger than about 45° (in each direction) relative to a direction perpendicular to a rolling direction such that an interval D of the linear strains or grooves satisfies a specific relation formula depending on the Cr content. A grain oriented electrical steel sheet is thereby obtained which has lower iron loss after domain refining treatment than conventional values.
    Type: Application
    Filed: January 24, 2002
    Publication date: October 31, 2002
    Inventors: Kunihiro Senda, Toshito Takamiya, Tadashi Nakanishi, Mitsumasa Kurosawa, Hiroaki Toda
  • Publication number: 20020153063
    Abstract: The present invention provides a non-oriented electrical steel sheet having ultra-high magnetic flux density and low core loss, characterized by: comprising a steel containing, in terms of wt %,
    Type: Application
    Filed: December 10, 2001
    Publication date: October 24, 2002
    Inventors: Ryutaro Kawamata, Takeshi Kubota
  • Patent number: 6454879
    Abstract: An austenitic, paramagnetic and corrosion-resistant material, particularly in media with high chloride concentrations, the material having high strength, yield strength, and ductility, including carbon, silicon, chromium, manganese, nitrogen, and optionally, nickel, molybdenum, copper, boron, and carbide-forming elements. The material is preferably substantially completely austenitic. A process utilizing alloying technology that includes a deformation and synergistically results in production of a ferrite-free material that is reliably paramagnetic, is corrosion-resistant, and has high yield strength, strength, and ductility. The material can be very beneficially used, for example, in connection with oil field technology, such as for bore rods and drilling string components as well as for precision-forged components, and for high strength attachment and connection elements.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: September 24, 2002
    Assignees: Schoeller-Bleckman Oilfield Technology GmbH & Co. KG, Bohler Edelstahl GmbH & Co. KG
    Inventors: Herbert Aigner, Günter Hochörtler, Josef Bernauer
  • Patent number: 6428632
    Abstract: According to the invention, a nonoriented electromagnetic steel sheet being small in the magnetic anisotropy in a high frequency zone and thus excellent in the magnetic properties as a rotating machine and having an excellent press formability such as punching property or the like can be obtained stably by adjusting a chemical composition of the oriented electromagnetic steel sheet to a given range, and establishing the following equation (1) between L, C average iron loss W15/50(L+C)[W/kg] and L, C average magnetic flux density B50(L+C)[T] with respect to measured values of magnetic properties using Epstein test pieces: B50(L+C)≧0.03·W15/50(L+C)+1.63  (1) and satisfying a ratio of D iron loss W10/400(D)[W/kg] to L, C average iron loss W10/400(L+C)[W/kg] by the following equation (2): W10/400(D)/W10/400(L+C)≦1.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: August 6, 2002
    Assignee: Kawasaki Steel Corporation
    Inventors: Toshiro Fujiyama, Keiji Sakai
  • Patent number: 6425962
    Abstract: A non-oriented electrical steel sheet excellent in permeability whose steel contains, in percentage by weight, 0.1%≦Si≦1.0%, 0.1%≦Mn≦0.8%, 0.1%≦Al≦1.0% and the balance of Fe and unavoidable impurities, and which has an ay transformation, an electrical resistivity of not less than 10×10−8 &OHgr;m and not greater than 32×10−8 &OHgr;m and a permeability &mgr;{fraction (15/60)} of not less than 1500 (Gauss/Oe); and a method of producing the same.
    Type: Grant
    Filed: April 13, 2000
    Date of Patent: July 30, 2002
    Assignee: Nippon Steel Corporation
    Inventors: Ryutaro Kawamata, Yoshihiro Arita, Shinichi Kanao, Kazufumi Hanzawa, Takeshi Kubota, Kenichi Murakami
  • Patent number: 6423157
    Abstract: Grain-oriented magnetic steel sheet made by the method comprising of hot rolling and final finish annealing, wherein (1) the O content in the steel slab is limited to up to about 30 wtppm; (2) for the entire steel sheet including an oxide film before final finish annealing, from among impurities, the Al content is limited to up to about 100 wtppm, and the contents of B, V, Nb, Se, S, and N, to up to about 50 wtppm; and (3) during final finish annealing, the N content in the steel is, at least in the temperature region of from about 850 to 950° C., limited within the range of from about 6 to 80 wtppm.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: July 23, 2002
    Assignee: Kawasaki Steel Corporation
    Inventors: Yasuyuki Hayakawa, Mitsumasa Kurosawa, Michiro Komatsubara
  • Patent number: 6416879
    Abstract: The object of the present invention is to provide an Fe-based amorphous alloy thin strip capable of realizing an excellent soft magnetic property for use in alternating current applications while keeping a high magnetic flux density even in a composition range with a high Fe content, and an Fe-based amorphous alloy thin strip with which a core having an excellent soft magnetic property can be manufactured, even if there occurs a temperature difference among different portions of the core during annealing. The present invention is an Fe-based amorphous alloy thin strip having a high magnetic flux density, consisting of the main component elements of Fe, Si, B, C, and P and unavoidable impurities, characterized by having: a composition, in atomic %, of 82<Fe≦90, 2≦Si<4, 5<B≦16, 0.02≦C≦4, and 0.2≦P≦12; Bs of 1.74 T or more after annealing; B80 exceeding 1.5 T; and a low core loss of 0.12 W/kg or less.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: July 9, 2002
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Yuichi Sato
  • 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: 20020005231
    Abstract: Method of making a grain oriented electromagnetic steel sheet having excellent magnetic properties, by a series of steps ranging from hot rolling to final finishing annealing for a silicon steel slab containing from about 0.001 to 0.07 wt % bismuth, wherein the average cooling rate for about five seconds measured immediately after the end of hot rolling is controlled within a range of from about 30 to 120° C./second; the value of the ratio PH2O/PH2 of the atmosphere for the soaking step in decarburization annealing is adjusted within a range of from about 0.45 to 0.70; and a treatment is provided for inhibiting decomposition of the surface inhibitor during final finishing annealing.
    Type: Application
    Filed: July 18, 2001
    Publication date: January 17, 2002
    Applicant: Kawasaki Steel Corporation
    Inventors: Kunihiro Senda, Toshito Takamiya, Makoto Watanabe, Mitsumasa Kurosawa
  • Publication number: 20020000265
    Abstract: Grain-oriented silicon steel sheet with Bi as an auxiliary inhibitor and a forsterite coating film having a Cr spinel oxide subscale of FeCr2O4 or FexMn1−xCr2O4 (0.6≦x≦1), made from a steel slab containing 0.005-0.20 wt % of Bi and 0.1-1.0 wt % of Cr.
    Type: Application
    Filed: July 18, 2001
    Publication date: January 3, 2002
    Applicant: Kawasaki Steel Corporation
    Inventors: Hiroaki Toda, Kunihiro Senda, Mitsumasa Kurosawa, Makoto Watanabe, Atsuhito Honda
  • Patent number: 6322638
    Abstract: Electromagnetic steel sheets which contain Cr in an amount of from about 1.5 to 20% by weight and Si in an amount of from about 2.5 to 10% by weight, while having a total amount of C and N of not larger than about 100 ppm by weight, and which has a specific resistivity of not smaller than about 60 &mgr;&OHgr;·cm.
    Type: Grant
    Filed: August 29, 2000
    Date of Patent: November 27, 2001
    Assignee: Kawasaki Steel Corporation
    Inventors: Shigeaki Takajo, Takako Yamashita, Akihiro Matsuzaki, Osamu Kondo
  • Patent number: 6312531
    Abstract: Soft magnetic powder of Fe—Al—Si system of which magnetostrictive constant &lgr; takes a positive value at the room temperature is employed to produce a magnetic composite article so that a temperature characteristic of core-loss of the article takes a negative value at the room temperature. Excellent magnetic characteristics such as a low core-loss and a high permeability can be obtained at a high frequency band.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: November 6, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobuya Matsutani, Yuji Mido, Kazuaki Onishi
  • Publication number: 20010030001
    Abstract: Grain-oriented magnetic steel sheet made by the method comprising of hot rolling and final finish annealing, wherein
    Type: Application
    Filed: March 5, 2001
    Publication date: October 18, 2001
    Applicant: Kawasaki Steel Corporation
    Inventors: Yasuyuki Hayakawa, Mitsumasa Kurosawa, Michiro Komatsubara
  • Patent number: 6296719
    Abstract: In the production of high permeability electrical steel, the control of condition of thin slab continuous casting allows to obtain advantageous solidification structures and precipitates. This, in turn, allows to decritize the process for controlling the grain dimensions and to add nitrogen to the cold rolled sheet, such as to immediately form aluminum nitride.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: October 2, 2001
    Assignee: Acciai Speciali Terni S.p.A.
    Inventors: Stefano Fortunati, Stefano Cicale', Giuseppe Abbruzzese
  • Patent number: 6290783
    Abstract: A finish annealed non-oriented electromagnetic steel sheet includes about 0.01 wt % or less of C, greater than about 1.0 wt % and at most about 3.5 wt % of Si, at least about 0.6 wt % and at most about 3.0 wt % of Al, at least about 0.1 wt % and at most about 2.0 wt % of Mn, at least about 2 ppm and at most about 80 ppm of one or more rare earth metals (REM), a maximum content of Ti and Zr being about 15 ppm and 80 ppm, respectively, wherein oxygen on the surface layer of the steel sheet is 1.0 g/m2 or less. Since the non-oriented electromagnetic steel sheet has desirable mechanical properties resulting from the increased amounts of Si and Al, a high magnetic flux density can be maintained without sacrificing a punching property as well as very low iron loss can be obtained even after stress relief annealing.
    Type: Grant
    Filed: February 1, 1999
    Date of Patent: September 18, 2001
    Assignee: Kawasaki Steel Corporation
    Inventors: Masaki Kawano, Yoshihiro Ozaki, Atsuhito Honda
  • Patent number: 6287703
    Abstract: This invention can considerably improve the adhesion property of a film to a matrix surface of a silicon steel sheet by forming an interface layer such as nitride-oxide layer of one or more selected from Fe, Si, Al and B or an extremely thin base film formed by finely dispersing nitride-oxide of one or more selected from Fe, Si, Al and B in the same film components as a tension insulating film at an interface between the matrix surface and the tension insulating film, or further by immersing in an aqueous solution of a chloride mainly composed of SiCl4 to dissolve the matrix surface or conducting a smoothening treatment or a pickling treatment with an aqueous solution containing SiCl4 prior to the formation of the interface layer, and hence ultra-low core loss grain oriented silicon steel sheets having a core loss considerably superior to that of the conventional one and an excellent magnetostriction property can be obtained very cheaply and in a higher productivity.
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: September 11, 2001
    Assignee: Kawasaki Steel Corporation
    Inventor: Yukio Inokuti
  • Patent number: 6287395
    Abstract: A high-energy weldable soft magnetic steel with high toughness in the heat-affected zone of weld joints, high specific electric resistance to reduce eddy currents, aging resistance and weathering resistance comprises 0.65 to <1.0% chromium, >1.0 to 2.0% silicon, 0.25 to 0.55% copper, 0.003 to 0.008% nitrogen, 0.15 to <0.6% manganese, 0.02 to 0.07% aluminumsolu., 0.01 to 0.02% titanium, 0 to 0.15% carbon, 0 to 0.045% phosphorus, the balance iron and unavoidable impurities.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: September 11, 2001
    Assignee: Thyssen Stahl AG
    Inventors: Udo Schriever, Hans-Joachim Tschersich
  • Patent number: 6284388
    Abstract: The present invention is directed to a method of forming an electrically insulating layer on a steel article such as a stack of electrical steel laminations or an individual, unstacked electrical steel lamination, comprising exposing the article to an oxidation atmosphere, and to a temperature (such as at least about 800° F.) for a time sufficient to form on the article an electrically insulating layer comprising hematite. The hematite layer is effective to provide the article with a surface resistivity characterized by an F-amp value of not greater than about 0.85 at a test pressure of 50 psi and a transfer surface roughness of about 10 microinches (Ra). Also featured is a steel article having the electrically insulating layer formed thereon.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: September 4, 2001
    Assignee: LTV Steel Company, Inc.
    Inventors: Richard J. Blotzer, Jeffrey P. Anderson, Barry A. Lauer
  • 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
  • Patent number: 6280862
    Abstract: Ultra-low iron grain-oriented silicon steel sheet which is made by forming a ceramic tensile coating including at least inner and outer portions of a nitride and/or a carbide, the outer portion having a coefficient of thermal expansion that is lower than that of the inner portion, and wherein the outermost portion has an insulating property.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: August 28, 2001
    Assignee: Kawasaki Steel Corporation
    Inventor: Yukio Inokuti
  • Patent number: 6270592
    Abstract: A magnetic core for use in a saturable reactor made of an Fe-based soft-magnetic alloy comprising as essential alloying elements Fe, Cu and M, wherein M is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo, and having an alloy structure at least 50% in area ratio of which being fine crystalline particles having an average particle size of 100 nm or less. The magnetic core has control magnetizing properties of a residual operating magnetic flux density &Dgr;Bb of 0.12 T or less, a total control operating magnetic flux density &Dgr;Br of 2.0 T or more, and a total control gain Gr of 0.10-0.20 T/(A/m) calculated by the equation: Gr=0.8×(&Dgr;Br−&Dgr;Bb)/Hr, wherein Hr is a total control magnetizing force defined as a control magnetizing force corresponding to 0.8×(&Dgr;Br−&Dgr;Bb)+&Dgr;Bb.
    Type: Grant
    Filed: September 24, 1998
    Date of Patent: August 7, 2001
    Assignee: Hitachi Metals, Ltd.
    Inventors: Shin Nakajima, Hirohiko Miki, Sadami Kubota, Mutsuhito Sakaguchi
  • Patent number: 6221501
    Abstract: The present invention is directed to a method of forming an electrically insulating layer on a steel article such as a stack of electrical steel laminations or an individual, unstacked electrical steel lamination, comprising exposing the article to an oxidation atmosphere, and to a temperature (such as at least about 800° F.) for a time sufficient to form on the article an electrically insulating layer comprising hematite. The hematite layer is effective to provide the article with a surface resistivity characterized by an F-amp value of not greater than about 0.85 at a test pressure of 50 psi and a transfer surface roughness of about 10 micro inches (Ra). Also featured is a steel article having the electrically insulating layer formed thereon.
    Type: Grant
    Filed: August 17, 1999
    Date of Patent: April 24, 2001
    Assignee: LTV Steel Company, Inc.
    Inventors: Richard J. Blotzer, Jeffrey P. Anderson, Barry A. Lauer
  • Patent number: 6139650
    Abstract: A non-oriented electromagnetic steel sheet contains 0.005 wt. % or less C, 0.2 wt. % or less P, 0.005 wt. % or less N, 4.5 wt. % or less Si, 0.05 to 1.5 wt. % Mn, 1.5 wt. % or less Al and 0.001 wt. % or less S, at least one element selected from the group of 0.001 to 0.05 wt. % Sb, 0.002 to 0.1 wt. % Sn, 0.0005 to 0.01 wt. % Se and 0.0005 to 0.01 wt. % Te; and the balance being Fe and inevitable impurities. The non-oriented electromagnetic steel sheet is produced by the steps of: hot-rolling a slab to form a hot-rolled steel sheet, cold-rolling the hot-rolled steel sheet to form a cold-rolled steel sheet; and finish annealing the cold-rolled steel sheet.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: October 31, 2000
    Assignee: NKK Corporation
    Inventors: Yoshihiko Oda, Nobuo Yamagami, Akira Hiura, Yasushi Tanaka, Noritaka Takahashi, Hideki Matsuoka, Atsushi Chino, Katsumi Yamada, Shunji Iizuka
  • Patent number: 6136456
    Abstract: Grain oriented electrical steel sheet with a very low iron loss and a method for producing the same, wherein the surface of the iron substrate of the grain oriented electrical steel sheet is subjected to an enhancement treatment of crystal grain orientation or surface smoothing to a mean roughness of about 0.20 .mu.m or less, electroplating a chromium plating layer on the substrate with heterogeneous growth, and applying a tension coating film to the plating layer.
    Type: Grant
    Filed: October 23, 1998
    Date of Patent: October 24, 2000
    Assignee: Kawasaki Steel Corporation
    Inventors: Michiro Komatsubara, Hiroi Yamaguchi, Minoru Takashima, Mineo Muraki
  • 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: 6129790
    Abstract: A ferromagnetic powder comprising ferromagnetic particles coated with a material that does not degrade at temperatures above 150.degree. 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: Grant
    Filed: February 11, 1999
    Date of Patent: October 10, 2000
    Assignee: Materials Innovation, Inc.
    Inventors: David S. Lashmore, Glenn L. Beane, Lev Deresh, Zonglu Hua
  • Patent number: 6129992
    Abstract: Provided are a high strength cold rolled steel sheet and a high strength plated steel sheet possessing improved geomagnetic shielding properties, that is, having a high relative permeability in a d.c. magnetic field around 0.3 Oe, a process for producing the same, and an explosion-proof band or an outer magnetic shielding material, for television cathode-ray tubes, using the steel sheet. An ultra low carbon steel, which has a carbon content of not more than 0.0060% and has been subjected to solid solution strengthening utilizing silicon and magnesium without relying upon precipitation strengthening, is deoxidized with silicon so that aluminum is substantially absent in the steel. Alternatively, when the ultra low carbon steel is deoxidized with aluminum, boron is added to inhibit the precipitation of AlN. Next, the deoxidized steel is finish rolled at 750 to 980.degree. C., cold rolled with a reduction ratio of 60 to 90%, and then annealed in the temperature range of 750.degree. C. to the Ac.sub.
    Type: Grant
    Filed: July 6, 1999
    Date of Patent: October 10, 2000
    Assignees: Nippon Steel Corporation, Sony Corporation
    Inventors: Yasuharu Sakuma, Satoru Tanaka, Kazuo Koyama, Yujiro Miyauchi, Takeshi Kubota, Atsushi Itami, Hiroaki Kato, Chohachi Sato, Teruo Takeuchi
  • Patent number: 6118365
    Abstract: In the ISDN telecommunication system, the connection between a digital local exchange and the network termination ensues via a public two-wire line at whose ends what are referred to as U-transformers reside. When the network termination leads to a terminal subscriber, then this is called a U.sub.k0 interface whereat the line length between the transformers can amount to up to 8 km. The bit error rate of the transmitted pulses must be <10.sup.-7, whereby the pulses have direct currents for the remote feed of the terminal subscribers that can amount to up to 80 mA superimposed on them. For such U.sub.K0 transformers, a toroidal tape core of a soft-magnetic, amorphous, magnetostriction-free alloy tape is employed. The manufactured toroidal tape core is tempered in a magnetic field, this thermal treatment ensuing in a protective gas atmosphere.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: September 12, 2000
    Assignee: Vacuumschmelze GmbH
    Inventors: Jorg Petzold, Johannes Beichler, Johannes Binkofski, Giselher Herzer, Volker Kieespies, Luigi Caprarella, Holger Wink
  • Patent number: RE38098
    Abstract: Amorphous alloys having the formula Fea Cob Nic Six By Mz are employed as monitoring strips for mechanically oscillating tags, for example for anti-theft protection, together with a source of a pre-magnetization field in which the strip is disposed so as to place the strip in an activated state. In the formula, M denotes one or more elements of groups IV through VII of the periodic table, including C, Ge and P, and the constituents in at % meet the following conditions: a lies between 20 and 74, b lies between 4 and 23, c lies between 5 and 50, with the criterion that b+c>14, x lies between 0 and 10, y lies between 10 and 20, and z lies between 0 and 5 with the sum x+y+z being between 12 and 21. These alloys have a resonant frequency associated therewith and when passed through an alternating field whose alternation frequency coincides with the resonant frequency, a pulse having a signal amplitude is produced.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: April 29, 2003
    Assignee: Vacuumschmelze GmbH
    Inventor: Giselher Herzer