Patents Assigned to Kawasaki Steel Corporation
  • Publication number: 20030165272
    Abstract: The data quantizing device quantizes coefficients subjected to orthogonal transform using a quantizing table. The device includes a comparing unit for deciding whether or not quantized data will be ‘0’ by comparing the orthogonal transformed coefficients with corresponding coefficients in the quantizing table, and a control unit for controlling the quantization so that only the orthogonal transformed coefficients with the quantized coefficients of not ‘0’ are quantized. The image data compressing device employs this data quantizing device, and this results in not only curtailing power consumption but also increasing the processing speed.
    Type: Application
    Filed: January 12, 2001
    Publication date: September 4, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventor: Kazunari Akaogi
  • Patent number: 6612745
    Abstract: In a sliding bearing device for continuous molten metal plating bath rolls, a shaft and a bearing composed of a sliding and contacting hard ceramic sinter are retained displaceably by a steel retainer, and by using such bearing device, therefore, a stable operation of continuous molten metal plating is achieved.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: September 2, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Tomoaki Nishizaka, Ichiro Tanokuchi
  • Publication number: 20030145920
    Abstract: The present invention presents a high tensile strength cold rolled steel sheet having excellent formability, impact resistance and strain age hardening characteristics, and the production thereof. As a specific means, a slab having a composition which contains, by mass %, 0.15% or less of C, 0.02% or less of Al, and 0.0050 to 0.0250% of N at N/Al of 0.3 or higher, and has N in a solid solution state at 0.0010% or more, is first hot rolled at the finish rolling delivery-side temperature of 800° C. or above, and is subsequently coiled at the coiling temperature of 750° C. or below to prepare a hot rolled plate. Then, after cold rolling, the hot rolled plate is continuously cooled at a temperature from the recrystallization temperature to 900° C. at a holding time of 10 to 120 seconds, and is cooled by primary cooling in which the hot rolled plate is cooled to 500° C. or below at a cooling rate of 10 to 300° C.
    Type: Application
    Filed: January 13, 2003
    Publication date: August 7, 2003
    Applicant: Kawasaki Steel Corporation
    Inventors: Chikara Kami, Akio Tosaka, Kazunori Osawa, Shinjiro Kaneko, Takuya Yamazaki, Kaneharu Okuda, Takashi Ishikawa
  • Patent number: 6602357
    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: Grant
    Filed: January 24, 2002
    Date of Patent: August 5, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Kunihiro Senda, Toshito Takamiya, Tadashi Nakanishi, Mitsumasa Kurosawa, Hiroaki Toda
  • Publication number: 20030143097
    Abstract: An sintered iron-based powder metal body with outstandingly lower re-compacting load and having a high density and a method of manufacturing an iron-based sintered component with fewer pores of a sharp shape and having high strength and high density, the method comprising mixing,
    Type: Application
    Filed: October 25, 2002
    Publication date: July 31, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Naomichi Nakamura, Satoshi Uenosono, Shigeru Unami, Masashi Fujinaga, Takashi Yoshimura, Mitsumasa Iijima, Shin Koizumi, Hiroyuki Anma, Yasuo Hatai
  • Publication number: 20030138342
    Abstract: A martensitic stainless steel sheet having superior corrosion resistance, toughness at the weld zones, and workability. The composition of the steel sheet is, on a mass basis: less than about 0.02% of carbon; about 1.0% or less of silicon; less than about 1.5% of manganese; about 0.04% or less of phosphorus; about 0.01% or less of sulfur; about 0.1% or less of aluminum; about 1.5% or more and less than about 4.0% of nickel; about 11% or more and less than about 15% of chromium; about 0.5% or more and less than about 2.0% of molybdenum; and less than about 0.02% of nitrogen, the balance being iron and unavoidable impurities, wherein 15.0%≦[Cr]+1.5×[Mo]+1.2×[Ni]≦20.0%; [C]+[N]<0.030%; [Ni]+0.5×([Mn]+[Mo])+30×[C]>3.0%; and 8.
    Type: Application
    Filed: December 23, 2002
    Publication date: July 24, 2003
    Applicant: Kawasaki Steel Corporation
    Inventors: Junichiro Hirasawa, Takumi Ujiro, Osamu Furukimi
  • Publication number: 20030129313
    Abstract: Gas wiping apparatus and method can reliably prevent edge overcoat and splash, and has face gas wiping nozzles extending widthwise of a strip material, a pair of baffle plates spaced from an edge of the strip material, an edge wiping nozzle disposed between baffle plates at its inner edge and adjacent the strip material edge, all with critical spacings relative to each other.
    Type: Application
    Filed: February 28, 2003
    Publication date: July 10, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Ichiro Tanokuchi, Sachihiro Iida
  • 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: 20030116745
    Abstract: A magnetite-iron based composite powder includes magnetite with a ratio of X-ray diffraction intensity to that of &agr;-Fe of about 0.001 to about 50 and has an average primary particle size of about 0.1 to about 10 &mgr;m. The composite powder can highly dehalogenate organic halogen compounds and exhibits satisfactory absorption power of high frequency electromagnetic waves after molding. An ultrafine nonferrous inorganic compound powder may adhere to the surface of the composite powder, or at least the composite powder may adhere to the surfaces of small particles of a nonferrous inorganic compound to thereby yield a composite powder composition. The composite powder can be produced by partial reduction of a material powder containing a hematite based powder or by complete reduction and subsequent partial oxidation of the material powder.
    Type: Application
    Filed: May 29, 2002
    Publication date: June 26, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Yukiko Ozaki, Satoshi Uenosono, Hiroki Nakamaru, Yukiko Nakamura, Shigeaki Takajo, Sawae Takajo, Shigeru Unami, Shingo Saito
  • Publication number: 20030116236
    Abstract: A method of manufacturing a grain-oriented steel sheet including hot-rolling a slab prepared using molten steel containing, by mass %, C of not more than about 0.08%, Si of about 2.0 to about 8.0% and Mn of about 0.005 to about 3.0%; optionally annealing the hot-rolled steel sheet; performing cold rolling once, or twice or more with intermediate annealing therebetween; performing primary recrystallization annealing in a low- or non-oxidizative atmosphere and adjusting the C content in the steel sheet after primary recrystallization annealing to be held in the range of about 0.005 to about 0.025 mass %; performing secondary recrystallization annealing; decarburization annealing; and, preferably, performing additional high-temperature continuous or batch annealing. A grain-oriented electrical steel sheet having a sufficiently high magnetic flux density and a low iron loss can be advantageously obtained even when it is manufactured without using an inhibitor.
    Type: Application
    Filed: July 23, 2002
    Publication date: June 26, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Yasuyuki Hayakawa, Hideo Yamagami, Seiji Okabe, Takeshi Imamura, Minoru Takashima, Mitsumasa Kurosawa
  • Patent number: 6581779
    Abstract: In a method of the magnetic loading of a sintering material, magnetically susceptible sinterable substances of high magnetization and fine substances of slidable dropping at low speed are segregated in great amounts in an upper portion of a sintering material layer deposited on a pallet. More of magnetically susceptible sinterable substances such as mill scale, returned ore and the like of good magnetic attachment and fine substances of low drop speed are caused to be segregated in the upper portion of that layer. A magnetic force is applied to a starting sintering material, during movement of the latter having been facilitated in its particle size segregation on a sloping chute, by means of a cylindrical magnetic drum having built therein a permanent magnet and disposed downwardly of the sloping chute.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: June 24, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Nobuyuki Oyama, Kouichi Nushiro, Katsutoshi Igawa, Seiji Taguchi, Norifumi Fujii, Kenji Takihira, Rikio Ono, Takahiro Kumeda
  • Patent number: 6579340
    Abstract: Fume dust is prevented when molten metal is poured into a vessel, and water spray of water mist is introduced into the vessel or onto the molten metal, creating a reduced level of oxygen concentration of about 12% by volume, preferably about 8% by volume, inside the vessel or at the molten metal surface.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: June 17, 2003
    Assignee: Kawasaki Steel Corporation
    Inventor: Tetsuo Akiyoshi
  • Publication number: 20030106622
    Abstract: A steel sheet composition contains appropriate amounts of C, Si, Mn, P, S, Al and N and 0.5 to 3.0% Cu. A composite structure of the steel sheet has a ferrite phase or a ferrite phase and a tempered martensite phase as a primary phase, and a secondary phase containing retained austenite in a volume ratio of not less than 1%. In place of the Cu, at least one of Mo, Cr, and W may be contained in a total amount of not more than 2.0%. This composition is useful in production of a high-ductility hot-rolled steel sheet, a high-ductility cold-rolled steel sheet and a high-ductility hot-dip galvanized steel sheet having excellent press formability and excellent stain age hardenability as represented by a &Dgr;TS of not less than 80 MPa, in which the tensile strength increases remarkably through a heat treatment at a relatively low temperature after press forming.
    Type: Application
    Filed: June 6, 2002
    Publication date: June 12, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Saiji Matsuoka, Tetsuo Shimizu, Kei Sakata, Osamu Furukimi
  • Patent number: 6572518
    Abstract: A cermet powder for thermal spray coating, which is sprayed on a roll surface of a conveyer roll inside a furnace for heat treating a high tensile strength steel strip thereby to form a coating film, comprises: an alloy powder containing 3 to 8 mass % of Al, 16 to 25 mass % of Cr, 0.1 to 1 mass % of Y, and at least one of Co and Ni as the residual, with respect to the whole amount of the cermet powder; and a ceramic powder containing at least one of 1 to 5 mass % of a boride and 5 to 10 mass % of a carbide, with respect to the whole amount of the cermet powder.
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: June 3, 2003
    Assignees: Kawasaki Steel Corporation, Praxair S. T. Technology, Inc.
    Inventors: Satoru Midorikawa, Shoichi Katoh
  • Publication number: 20030094217
    Abstract: A ferritic stainless steel sheet contains abut 0.01 percent by mass or less of carbon; about 1.0 percent by mass or less of silicon; about 1.5 percent by mass or less of manganese; about 11 to about 23 percent by mass of chromium; about 0.06 percent by mass or less of phosphorous; about 0.03 percent by mass or less of sulfur; about 1.0 percent by mass or less of aluminum; about 0.04 percent by mass or less of nitrogen; about 0.0005 to about 0.01 percent by mass of boron; about 0.3 percent by mass or less of vanadium; about 0.8 percent by mass or less of niobium and/or about 1.0 percent by mass or less of titanium wherein 18≦Nb/(C+N)+2(Ti/(C+N))≦60; and the balance being iron and unavoidable impurities. The average crystal grain diameter is about 40 &mgr;m or less and the average surface roughness is about 0.3 &mgr;m or less.
    Type: Application
    Filed: October 29, 2002
    Publication date: May 22, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Yoshihiro Yazawa, Osamu Furukimi, Yasushi Kato, Yoshihiro Ozaki
  • 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: 6558815
    Abstract: The hot dip Zn galvanized steel sheet has excellent balance between tensile strength and ductility and excellent coating adhesion, an average composition of a base steel thereof includes: 0.05-0.25 mass % of C; not more than 2.0 mass % of Si; 1.0-2.5 mass % of Mn; and 0.005-0.10 mass % of Al, wherein the C content at the base steel surface layer portion right under a coating layer is not more than 0.02 mass %, the base steel structure contains not less than 50% of martensite phase, the martensite phase including both tempered martensite phase and fine size martensite phase, and the remaining portion of the base steel structure being formed by ferrite phase and residual austenite phase. A method of producing the hot dip Zn galvanizing steel sheet is described.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: May 6, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Yoshitsugu Suzuki, Chiaki Kato
  • Patent number: 6557623
    Abstract: Molten steel is poured using an immersion nozzle and a direct current magnetic field zone is applied to a cast slab over the entire width in the thickness direction thereof at a predetermined distance below the molten metal level in a continuously-casting mold. The immersion nozzle is provided with ejection holes located in at least upper and lower stages, at least one lower ejection hole is disposed such that these satisfy the following formula (1). The supply rate of molten steel from the upper ejection holes is set smaller than the rate consumed by solidification in an upper pool, and a particular solute element is added to the molten steel in the upper pool. 0<h<(½)·w·tan &thgr;  (1) where, &thgr;: downward angle of lower ejection hole(s) (°); w: length of mold in width direction (m); and h: distance from center of lower ejection hole to center of height of magnetic pole (m).
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: May 6, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Hiromitu Shibata, Yasuo Kishimoto, Shuji Takeuchi, Koji Yamaguchi
  • Patent number: 6555249
    Abstract: The coated steel sheet includes a zinc phosphate coating containing Mg on a surface of a galvanized steel sheet, and an orthophosphoric acid ester-containing coating on a surface of the zinc phosphate coating. The coated steel sheet has no coating fall-off even during a chemical conversion treatment step of an automobile producing line and has excellent perforative corrosion resistance either with no-painting or after electrodeposition painting, chemical conversion treatability and press formability.
    Type: Grant
    Filed: May 17, 2001
    Date of Patent: April 29, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Kyoko Hamahara, Hisatada Nakakoji, Kazuo Mochizuki
  • Publication number: 20030077448
    Abstract: An iron-based powder including a heat-resistant insulate coating and a powder core are suggested. A paint containing silicone resin and pigment is added to a raw material powder primarily containing a ferromagnetic metal, especially, iron, agitation and mixing are performed and, thereafter, a drying treatment is performed so as to form a coating containing silicone resin and pigment on the surface of the iron-based powder. The ratio of the silicone resin content to the pigment content in the coating is preferably 0.01 or more, but less than 4.0 on a mass basis. The pigment is preferably at least one selected from the group consisting of metal oxides, metal nitrides, metal carbides, minerals, and glass. The paint may be sprayed to the iron-based powder in a fluidized state. A coating containing at least one of Si compounds, Ti compounds, Zr compounds, P compounds, and Cr compounds may be formed as a lower layer of the aforementioned coating.
    Type: Application
    Filed: March 21, 2002
    Publication date: April 24, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Masateru Ueta, Naomichi Nakamura, Satoshi Uenosono