Patents by Inventor Hidekuni Murakami

Hidekuni Murakami has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20090301609
    Abstract: The invention provides a non-oriented electrical steel sheet excellent in yield strength for use as an iron core material for high rpm motors that does not sacrifice yield or productivity in motor core punching or steel sheet production, which non-oriented electrical steel sheet is given a chemical composition of, in mass %, C: 0.01 to 0.05%, Si: 2.0 to 4.0%, Mn: 0.05 to 0.5%, Al: 3.0% or less and Nb: 0.01 to 0.05%, and optionally Ni at a preferable content of more than 0.5% and less than 3.0%, the balance being Fe and unavoidable impurities, Mn and C contents expressed in mass % are made to satisfy Mn?0.6?10×C, recrystallized portion area fraction is made 50% or greater, yield strength in tensile testing is made 650 MPa or greater, and average-grain diameter viewed in steel sheet cross-section is made 40 ?m or less, and electrical steel sheet production is conducted using a hot-rolled sheet whose transition temperature in impact testing is 70° C. or less.
    Type: Application
    Filed: June 15, 2007
    Publication date: December 10, 2009
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yoshihiro Arita, Hidekuni Murakami, Yutaka Matsumoto, Saori Haranaka, Takeshi Kubota
  • Publication number: 20090047168
    Abstract: The present invention provides a continuously cast enameled steel sheet with remarkably excellent fishscale resistance improving the ability to form spaces in the steel sheet so as to increase the hydrogen trap ability, and a method of production of the same, comprised of steel having as ingredients, by mass %, C: 0.010% or less, Mn: 0.03 to 1.30%, Si: 0.100% or less, Al: 0.030% or less, N: 0.0055% or less, P: 0.035% or less, S: 0.08% or less, O: 0.005 to 0.085%, and B: 0.0003 to 0.0250% and including in the steel sheet not integral or integral oxides differing in mass concentration of B or Mn. The ratio of the maximum concentration and minimum concentration is made 1.2 or more. When not integral, they are present with a straight line distance between centers of the oxides differing in concentration of 0.10 ?m to 20 ?m and with an angle of the line connecting the centers of the two oxides of within ±10° from the rolling direction.
    Type: Application
    Filed: November 9, 2006
    Publication date: February 19, 2009
    Inventors: Hidekuni Murakami, Satoshi Nishimura
  • Publication number: 20080318029
    Abstract: The present invention provides enamelware and a glaze improving the bondability between the steel substrate and enamel layer and superior in resistance to dew point corrosion by sulfuric acid and hydrochloric acid, that is, a steel substrate of a composition containing, by mass %, Cu: 0.05 to 0.5%, Si: 0.1 to 2.0%, Mn: 0.05 to 2.0%, P: 0.005 to 0.10%, and S: 0.005 to 0.1%, restricting C to C: 0.20% or less, and comprising a balance of Fe and unavoidable impurities on the surface of which an enamel layer of a thickness of 50 to 700 ?m is provided. At that time, the content of Co oxides in the enamel layer is made, converted to Co, 0.01 to 10% and/or the content of Ni oxides is made, converted to Ni, 0.05 to 20% or the total content of Ni in the steel substrate and enamel layer is made 0.005 to 4.5% with respect to the total mass of the enamelware and/or the total content of Co is made 0.008 to 4.0% with respect to the total mass of the enamelware.
    Type: Application
    Filed: January 12, 2007
    Publication date: December 25, 2008
    Inventors: Satoshi Nishimura, Shunji Sakamoto, Hidekuni Murakami
  • Publication number: 20080053576
    Abstract: The present invention stably provides a high-strength hot-dip galvanized steel sheet having a high tensile strength and no non-plated portions and being excellent in workability and surface properties even when the employed equipment has only a reduction annealing furnace and a steel sheet containing relatively large amounts of Si, Mn and Al that are regarded as likely to cause non-plated portions is used as the substrate.
    Type: Application
    Filed: October 24, 2007
    Publication date: March 6, 2008
    Applicant: Nippon Steel Corporation
    Inventors: Yoshihisa Takada, Masayoshi Suehiro, Masao Kurosaki, Hidekuni Murakami, Hiroyasu Fujii, Haruhiko Eguchi, Hisaaki Sato
  • Patent number: 7294412
    Abstract: The present invention stably provides a high-strength hot-dip galvanized steel sheet having a high tensile strength and no non-plated portions and being excellent in workability and surface properties even when the employed equipment has only a reduction annealing furnace and a steel sheet containing relatively large amounts of Si, Mn and Al that are regarded as likely to cause non-plated portions is used as the substrate.
    Type: Grant
    Filed: January 15, 2004
    Date of Patent: November 13, 2007
    Assignee: Nippon Steel Corporation
    Inventors: Yoshihisa Takada, Masayoshi Suehiro, Masao Kurosaki, Hidekuni Murakami, Hiroyasu Fujii, Haruhiko Eguchi, Hisaaki Sato
  • Publication number: 20070062611
    Abstract: The present invention has as its object to stably produce a high strength electrical steel sheet and a processed part of the same which is high in strength and has wear resistant and is superior in magnetic flux density and core loss without greatly changing the cold rollability and production processes from those of conventional electrical steel sheet and provides a high strength electrical steel sheet characterized by containing, by mass %, C: 0.06% or less, Si: 0.2 to 6.5%, Mn: 0.05 to 3.0%, P: 0.30% or less, S or Se: 0.040% or less, Al: 2.50% or less, Cu: 0.6 to 8.0%, N: 0.0400% or less, and a balance of Fe and unavoidable impurities and containing in the steel a metal phase composed of Cu of a size of 0.1 ?m or less. The method of production of the same comprises holding in a temperature range of 300° C. to 720° C. for 5 seconds or more for heat treatment.
    Type: Application
    Filed: October 6, 2004
    Publication date: March 22, 2007
    Applicant: NIPPON STEEL CORPORATION
    Inventor: Hidekuni Murakami
  • Publication number: 20060124907
    Abstract: The present invention stably provides a high-strength hot-dip galvanized steel sheet having a high tensile strength and no non-plated portions and being excellent in workability and surface properties even when the employed equipment has only a reduction annealing furnace and a steel sheet containing relatively large amounts of Si, Mn and Al that are regarded as likely to cause non-plated portions is used as the substrate.
    Type: Application
    Filed: January 15, 2004
    Publication date: June 15, 2006
    Inventors: Yoshihisa Takada, Masayoshi Suehiro, Masao Kurosaki, Hidekuni Murakami, Hiroyasu Fujii, Haruhiko Eguchi, Hisaaki Sato
  • Publication number: 20050236078
    Abstract: To provide a non-aging steel sheet for vitreous enameling, the steel sheet being excellent in resistance to bubbles and black spots, without the employment of decarbonization and denitrification annealing that raises the cost of production and also without the addition of expensive elements such as Nb, Ti, etc. that raise the cost of alloys. The steel sheet comprises, in mass, to C: 0.0050% or less, Si: 0.50% or less, Mn: 0.005 to 1.0%, P: 10×(B?11/14×N) to 0.10%, S: 0.080% or less, Al: 0.050% or less, N: 0.0005 to 0.020%, B: 0.60×N to 0.020%, and O: 0.002 to 0.0800%, and the shape of B nitrides is controlled mainly by adjusting hot-rolling conditions.
    Type: Application
    Filed: March 6, 2003
    Publication date: October 27, 2005
    Inventors: Hidekuni Murakami, Satoshi Nishimura
  • Publication number: 20040244885
    Abstract: The present invention relates to a steel sheet for Vitreous enameling excellent in enameling properties (bubbling and black spot resistance, enamel adhesiveness and fish scale resistance) and workability, and a method for producing the same, and is characterized in that the steel sheet contains, in mass of, C: 0.010% or less, Mn: 0.03 to 1.3%, Si: 0.03% or less, Al: 0.02% or less, N: 0.0055% or less, P: below 0.035%, and S: over 0.025% to 0.08%; and the density change of the steel sheet from before an annealing to after an annealing at 850° C. for 20 hours, in a hydrogen atmosphere is 0.02% or more.
    Type: Application
    Filed: April 28, 2004
    Publication date: December 9, 2004
    Inventors: Hidekuni Murakami, Satoshi Nishimura, Shiro Sanagi
  • Patent number: 6808678
    Abstract: Disclosed is the provision of a non-aging, highly anti-seed and anti-black-speck steel plate for enameling without relying upon decarbonization-denitrification annealing involving increased production cost, and without the addition of expensive elements, such as niobium and titanium involving increased alloying cost. This steel plate is produced by adopting a steel composition comprising, by weight, carbon: not more than 0.0018%, silicon: not more than 0.020%, manganese: 0.10 to 0.30%, phosphorus: 0.010 to 0.030%, sulfur: not more than 0.030%, aluminum: not more than 0.005%, nitrogen: 0.0008 to 0.0050%, boron: not more than 0.0050% and not less than 0.6 time the nitrogen content, and oxygen: 0.010 to 0.05%, and regulating the chemical composition of the steel and regulating mainly hot rolling conditions to regulate the form of nitrides.
    Type: Grant
    Filed: February 21, 2002
    Date of Patent: October 26, 2004
    Assignee: Nippon Steel Corporation
    Inventors: Hidekuni Murakami, Satoshi Nishimura, Kazuhisa Kusumi, Shiroh Sanagi
  • Patent number: 6562152
    Abstract: A TRIP-type high strength steel plate having good workability is provided which, while reducing the amount of alloying elements added which increase the production cost, ensures a contemplated retained austenite structure, has good adhesion to zinc plating, and can also be applied to highly corrosion resistant surface treated steel plates. The high strength steel plate having improved workability and plating adhesion is such that a high concentration, i.e., 0.03 to 2.0% by weight, of nitrogen is incorporated, the contents of silicon and aluminum, which form nitride, are preferably regulated respectively to not more than 0.5% by weight and not more than 0.3% by weight, and, in addition, calcium, sodium, magnesium, etc. are optionally added to control the formation of iron nitride, whereby the volume fraction of the retained austenite phase in the metal structure is regulated to 3 to 20% by weight.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: May 13, 2003
    Assignee: Nippon Steel Corporation
    Inventors: Hidekuni Murakami, Yoshihisa Takada, Masayoshi Suehiro
  • 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
  • Publication number: 20020144755
    Abstract: Disclosed is the provision of a non-aging, highly anti-seed and anti-black-speck steel plate for enameling without relying upon decarbonization-denitrification annealing involving increased production cost, and without the addition of expensive elements, such as niobium and titanium involving increased alloying cost. This steel plate is produced by adopting a steel composition comprising, by weight, carbon: not more than 0.0018%, silicon: not more than 0.020%, manganese: 0.10 to 0.30%, phosphorus: 0.010 to 0.030%, sulfur: not more than 0.030%, aluminum: not more than 0.005%, nitrogen: 0.0008 to 0.0050%, boron: not more than 0.0050% and not less than 0.6 time the nitrogen content, and oxygen: 0.010 to 0.05%, and regulating the chemical composition of the steel and regulating mainly hot rolling conditions to regulate the form of nitrides.
    Type: Application
    Filed: February 21, 2002
    Publication date: October 10, 2002
    Inventors: Hidekuni Murakami, Satoshi Nishimura, Kazuhisa Kusumi, Shiroh Sanagi
  • Patent number: 6427860
    Abstract: A can lid made of a metal sheet having a resin coating on at least one surface thereof and superior in can openability, having an outer peripheral flat portion and an inner peripheral flat portion straddling a score line further having an outer bead and inner bead at the sides of the outer peripheral flat portion and the inner peripheral flat portion opposite to the score line, and having a cross-section where the score line becomes gradually thinner from the thicknesses of the outer peripheral flat portion and the inner peripheral flat portion and a process for forming the same.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: August 6, 2002
    Assignee: Nippon Steel Corporation
    Inventors: Hiroshi Nishida, Hidekuni Murakami, Masayoshi Suehiro, Shoji Nosaka
  • Publication number: 20020017342
    Abstract: A TRIP-type high strength steel plate having good workability is provided which, while reducing the amount of alloying elements added which increase the production cost, ensures a contemplated retained austenite structure, has good adhesion to zinc plating, and can also be applied to highly corrosion resistant surface treated steel plates. The high strength steel plate having improved workability and plating adhesion is such that a high concentration, i.e., 0.03 to 2.0% by weight, of nitrogen is incorporated, the contents of silicon and aluminum, which form nitride, are preferably regulated respectively to not more than 0.5% by weight and not more than 0.3% by weight, and, in addition, calcium, sodium, magnesium, etc. are optionally added to control the formation of iron nitride, whereby the volume fraction of the retained austenite phase in the metal structure is regulated to 3 to 20% by weight.
    Type: Application
    Filed: June 27, 2001
    Publication date: February 14, 2002
    Inventors: Hidekuni Murakami, Yoshihisa Takada, Masayoshi Suehiro
  • Publication number: 20010037841
    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: Application
    Filed: April 6, 2001
    Publication date: November 8, 2001
    Inventors: Ken-ichi Murakami, Takashi Morohoshi, Tomoji Kumano, Ryutaro Kawamata, Takeshi Kubota, Masafumi Zeze, Hidekuni Murakami, Shinichi Kanao
  • Patent number: 5486241
    Abstract: The present invention provides a non-aging at room temperature ferritic single-phase cold-rolled steel sheet or hot-dip galvanized steel sheet for deep drawing and having excellent fabrication embrittlement resistance and paint-bake hardenability, by heating a slab comprising, in terms of % by weight, 0.0001 to 0.0015% of C, not more than 1.2% of Si, 0.03 to 3.0% of Mn, 0.01 to 0.15% of P, 0.0010 to 0.020% of S, 0.005 to 0.1% of Al, 0.0001 to 0.0080% of N and 0.0001 to 0.0030% of B and optionally 0.1 to 3% of Cr with the balance consisting of Fe and unavoidable impurities, hot-rolling the heated slab at a finishing temperature of not lower than (Ar.sub.3 --100).degree. C., cooling the hot-rolled coil within 1 sec after the hot rolling at a rate of not less than 50.degree. C./sec from the finishing temperature to a temperature in the range of from 600.degree. to 750.degree. C.
    Type: Grant
    Filed: June 29, 1994
    Date of Patent: January 23, 1996
    Assignee: Nippon Steel Corporation
    Inventors: Kohsaku Ushioda, Naoki Yoshinaga, Yoshikazu Matsumura, Osamu Akisue, Kunio Nishimura, Hidekuni Murakami