Patents Assigned to Nippon Steel
  • Publication number: 20240141469
    Abstract: High strength plated steel sheet having high hydrogen embrittlement resistance, that is, alloyed hot dip galvannealed steel sheet including steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50% and a alloyed hot dip galvannealed layer deposited on at least one surface of the steel sheet to 10 to 100 g/m2 and containing Fe: 5.0 to 15.0% and Al: 0.01 to 1.0%, having an internal oxidation layer including grain boundary oxides in a surface layer of the steel sheet, when examining a cross-section of a surface layer of the steel sheet, a Ratio A of the length of the grain boundary oxides projected an interface of the steel sheet and the alloyed hot dip galvannealed layer to the length of interface is 50% or more and 100% or less, and a surface depleted layer with a steel composition not including the grain boundary oxides which satisfies, by mass %, Si?0.6% and Al?0.05% is included at a depth of ½ of the average depth of the internal oxidation layer.
    Type: Application
    Filed: March 14, 2022
    Publication date: May 2, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Keitaro MATSUDA, Takuya MITSUNOBU, Masaaki URANAKA, Jun MAKI, Hiroshi TAKEBAYASHI
  • Publication number: 20240144504
    Abstract: A crankshaft shape inspection method includes: acquisition step that acquires three-dimensional point cloud data of a surface of a crankshaft S; generation step that generates, while using the three-dimensional point cloud data, first point cloud data based on point cloud data generated by performing isolated point removal processing that removes data points whose distance to the nearest neighbor data point is equal to or more than first threshold value Th1 and generates second point cloud data based on point cloud data generated by performing isolated point removal processing that removes data points whose distance to the nearest neighbor data point is equal to or more than second threshold value Th2 (>the first threshold value Th1); and a calculation step that calculates a side dimension of a counterweight SC using the first point cloud data and calculates a longitudinal position of the counterweight SC using the second point cloud data.
    Type: Application
    Filed: April 22, 2021
    Publication date: May 2, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yoshito ISEI, Kousuke SAKAI, Shinya IKEDA, Yuki USUTANI
  • Publication number: 20240141467
    Abstract: This steel sheet has a predetermined chemical composition, and has, at a t/4-position which is a position at a distance of t/4 from the surface in a sheet thickness direction cross section when the sheet thickness is defined as t, a metal structure including 20% or more of ferrite and a total of 40% or more of bainite and martensite in volume fraction, the remaining portion being at least one selected from retained austenite and perlite. In a square-shaped area in which the length of one side is t/4 and which is centered at the t/4-position in the sheet thickness direction cross section, when the Mn concentration is measured at multiple measurement points located apart at a 1 ?m-interval, the proportion of measurement points in which the Mn concentration is at least 1.1 times of the average value of the Mn concentration at all the measurement points is less than 10.0%. The steel sheet has a tensile strength of 980 MPa or more.
    Type: Application
    Filed: February 18, 2022
    Publication date: May 2, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventor: Yuya SUZUKI
  • Publication number: 20240141463
    Abstract: This non-oriented electrical steel sheet has a predetermined chemical composition, one or more particles that are a precipitate of a sulfide or an oxysulfide of one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd or both the sulfide and the oxysulfide and have a diameter of more than 0.5 ?m are present in a visual field of 10000 ?m2, and, when EBSD observation is performed on a surface parallel to a steel sheet surface, in a case where a total area is indicated by Stot, an area of {100} orientated grains is indicated by S100, an area of orientated grains in which a Taylor factor M becomes more than 2.8 is indicated by Styl, a total area of orientated grains in which the Taylor factor M becomes 2.8 or less is indicated by Stra, an average KAM value of the {100} orientated grains is indicated by K100, and an average KAM value of the orientated grains in which the Taylor factor M becomes more than 2.8 is indicated by Ktyl, 0.20?Styl/Stot?0.85, 0.05?S100/Stot?0.
    Type: Application
    Filed: March 18, 2022
    Publication date: May 2, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Tesshu MURAKAWA, Minako FUKUCHI
  • Publication number: 20240141471
    Abstract: A method of forming an Al—Zn—Si—Mg alloy coating on a steel strip includes dipping steel strip into a bath of molten Al—Zn—Si—Mg alloy and forming a coating of the alloy on exposed surfaces of the steel strip. The method also includes controlling conditions in the molten coating bath and downstream of the coating bath so that there is a uniform Al/Zn ratio across the surface of the coating formed on the steel strip. An Al—Zn—Mg—Si coated steel strip includes a uniform Al/Zn ratio on the surface or the outermost 1-2 ?m of the Al—Zn—Si—Mg alloy coating.
    Type: Application
    Filed: November 3, 2023
    Publication date: May 2, 2024
    Applicants: Bluescope Steel Limited, Nippon Steel Corporation, Nippon Steel Coated Sheet Corporation
    Inventors: Wayne Andrew RENSHAW, Cat TU, Joe WILLIAMS, Jason HODGES, Shiro FUJII, Nobuyuki SHIMODA, Shuichi KONDO, Takashi HIRASAWA
  • Patent number: 11970752
    Abstract: Provided are: a steel sheet having a high strength and excellent hydrogen embrittlement resistance; and a method of producing the same. The steel sheet has prescribed chemical composition and structure, in which a standard deviation ? of Mn concentration satisfies ??0.15 Mnave (wherein, Mnave represents an average Mn concentration) and a region with a Mn concentration of higher than (Mnave+1.3?) has a circle-equivalent diameter of less than 10.0 ?m. The method of producing the steel sheet includes: the hot rolling step that includes finish rolling a slab having a prescribed chemical composition under prescribed conditions; the step of coiling the thus obtained hot-rolled steel sheet at a coiling temperature of 450 to 700° C.; and the step of cold rolling the hot-rolled steel sheet and subsequently annealing this steel sheet at 800 to 900° C.
    Type: Grant
    Filed: March 12, 2020
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kengo Takeda, Hiroyuki Kawata, Takafumi Yokoyama, Katsuya Nakano
  • Patent number: 11969779
    Abstract: A mandrel 10 for producing a thin-walled bent tube having a bending portion with high strength and a small radius of curvature by rotary draw bending without either cracks in an outside of bend or wrinkles and buckling in an inside of bend occurring includes a shank 14, a connection mechanism 15 and a mandrel ball 16. In a cross-section orthogonal to an axial direction of the mandrel ball 16 at a central position in the axial direction of the mandrel ball 16, the mandrel ball 16 has a first position 19 and a second position 20 at which a first straight line m that passes through a mandrel ball center 17 meets an outer periphery 21 of the mandrel ball. Further, a ratio (L1/L2) between a dimension L1 from the mandrel ball center 17 to the first position 19 and a dimension L2 from the mandrel ball center 17 to the second position 20 is in a range of 0.915 to 0.976.
    Type: Grant
    Filed: February 2, 2022
    Date of Patent: April 30, 2024
    Assignee: Nippon Steel Corporation
    Inventors: Shohei Tamura, Hidehiro Arita
  • Patent number: 11970751
    Abstract: The grain-oriented electrical steel sheet according to the present embodiment is a grain-oriented electrical steel sheet having a base steel sheet (1), an intermediate layer (4) disposed to be in contact with the base steel sheet (1), and an insulation coating (3) disposed to be in contact with the intermediate layer (4). The grain-oriented electrical steel sheet according to the present embodiment includes a surface of the base steel sheet (1) having a strain region (D) which extends in a direction intersecting a rolling direction of the base steel sheet (1), and a crystalline phosphorus oxide M2P4O13 present in the insulation coating (3) on the strain region (D) in a cross-sectional view of a surface parallel to the rolling direction and a sheet thickness direction of the base steel sheet (1). (M means at least one or both of Fe and Cr.
    Type: Grant
    Filed: January 16, 2020
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yoshiyuki Ushigami, Shinji Yamamoto, Hideyuki Hamamura, Takashi Kataoka, Shunsuke Okumura
  • Patent number: 11973369
    Abstract: A laminated core includes a plurality of electrical steel sheets stacked on each other, wherein, among the plurality of electrical steel sheets, both of the electrical steel sheets located on a first side in a stacking direction and the electrical steel sheets located on a second side in the stacking direction are fastened to each other but are not adhered to each other, and the electrical steel sheets located in a center in the stacking direction are adhered to each other but are not fastened to each other.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hiroshi Fujimura, Takeaki Wakisaka, Ryu Hirayama
  • Patent number: 11969969
    Abstract: What is provided is a new and improved metal-carbon fiber reinforced resin material composite in which the galvanic corrosion of dissimilar materials of a metal member is suppressed and electrodeposition coatability is excellent and a method for manufacturing the metal-carbon fiber reinforced resin material composite. A metal-carbon fiber reinforced resin material composite according to the present invention has a metal member, a resin coating layer disposed on at least a part of a surface of the metal member, and a carbon fiber reinforced resin material containing a matrix resin and a carbon fiber material present in the matrix resin, the resin coating layer contains any one or more kinds selected from the group consisting of metal particles, intermetallic compound particles, conductive oxide particles, and conductive non-oxide ceramic particles as conductive particles and further contains a binder resin, and the conductive particles have a powder resistivity at 23° C. to 27° C. of 7.
    Type: Grant
    Filed: April 2, 2019
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kohei Ueda, Yasuaki Kawamura, Masumi Koori, Masaharu Ibaragi
  • Patent number: 11970758
    Abstract: This hot-rolled steel sheet has a predetermined chemical composition. The metallographic structure at a sheet thickness ¼ depth from a surface and at a center position in a sheet width direction in a sheet width cross section parallel to a rolling direction contains, by area %, 77.0% to 97.0% of bainite and tempered martensite in total, 0% to 5.0% of ferrite, 0% to 5.0% of pearlite, 3.0% or more of residual austenite, and 0% to 10.0% of martensite. The average grain size of the metallographic structure excluding the residual austenite is 7.0 ?m or less. The C concentration in the residual austenite is 0.5 mass % or more. The number density of iron-based carbides having a diameter of 20 nm or more is 1.0×106 carbides/mm2 or more.
    Type: Grant
    Filed: October 21, 2019
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hiroshi Shuto, Akifumi Sakakibara, Shinsuke Kai, Koutarou Hayashi, Hiroshi Kaido
  • Patent number: 11970759
    Abstract: The seamless steel pipe according to the present disclosure includes a chemical composition consisting of, in mass %, C: 0.030% or less, Si: 1.00% or less, Mn: 1.00% or less, P: 0.030% or less, S: 0.0050% or less, Al: 0.001 to 0.100%, N: 0.0500% or less, O: 0.050% or less, Ni: 5.00 to 6.50%, Cr: more than 10.00 to 13.40%, Cu: more than 1.50 to 3.50%, Mo: 1.00 to 4.00%, V: 0.01 to 1.00%, Ti: 0.050 to 0.300%, and Co: 0.010 to 0.300%, with the balance being Fe and impurities, and satisfying Formula (1), wherein a depassivation pH of an inner surface is 3.00 or less. Cr+2.0 Mo+0.5 Ni+2.0 Cu+0.5 Co?20.
    Type: Grant
    Filed: October 1, 2019
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kyohei Kanki, Masayuki Sagara, Yusaku Tomio, Daisuke Matsuo
  • Patent number: 11970750
    Abstract: There is provided a non-oriented electrical steel sheet in which, in a cross section of a base material in a sheet thickness direction, the number density N2-5 of precipitates with an equivalent circle diameter of 50 to 500 nm present in a range of 2.0 to 5.0 ?m from the surface of the base material in the sheet thickness direction is 0.30 pieces/?m2 or less, and the relationship between the number density N2-5 and the number density N0-2 of precipitates with an equivalent circle diameter of 50 to 500 nm present in a range from the surface of the base material to 2.0 ?m satisfies Formula (1): (N2-5)/(N0-2)?0.5??Formula (1).
    Type: Grant
    Filed: March 31, 2022
    Date of Patent: April 30, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Nobusato Morishige, Takeru Ichie, Masato Yasuda, Masahide Urago, Fuminobu Murakami, Daichi Hamada, Atsushi Shibayama, Kazumi Mizukami, Daisuke Itabashi
  • Publication number: 20240133007
    Abstract: A hot-stamp formed body has a predetermined chemical composition and has a microstructure including, by area ratio, martensite: 90% to 100% and a remainder in the microstructure: 0% to 10%. The percentage of martensite having a GAIQ value of 40000 or less in all of the martensite is less than 5.0%, an average grain size of prior austenite grains is 6.0 ?m or less, and a standard deviation of grain sizes of the prior austenite grains is 2.6 ?m or less.
    Type: Application
    Filed: September 19, 2022
    Publication date: April 25, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Shingo FUJINAKA, Hitomi NISHIBATA
  • Publication number: 20240131626
    Abstract: There is provided a blank in which two or more starting materials that overlap each other are joined with each other by laser welding, including the blank has a single layer region, in which only one of the starting materials is present, and a multi-layer region, in which two or more of the starting materials overlap each other, laser welding is continuously applied to the multi-layer region and the single layer region, and one end of a laser weld zone is located at an end portion of the single layer region of the blank, and the one end forms a concave-shaped welding end portion having a concave shape when the blank is viewed from an end face.
    Type: Application
    Filed: March 29, 2021
    Publication date: April 25, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Masahiko ABE, Yasuhiro ITO
  • Publication number: 20240133006
    Abstract: A martensitic stainless steel sheet for a brake disc rotor, characterized by containing predetermined components and having, in a mother phase, precipitates with a particle size of 2 ?m or less and a density of 0.01 to 20 pieces/?m2. The precipitates finely present in hot rolling and hot-rolled sheet annealing improves productivity in hardening, improves temper softening resistance of the steel sheet in use as a component, inhibits cracking in hot stamping, and inhibits reduction in high-temperature strength. Accordingly, the martensitic stainless steel sheet excellent in temper softening resistance, hardenability, formability, and high-temperature strength that is applicable to the disc rotor is provided.
    Type: Application
    Filed: February 8, 2022
    Publication date: April 25, 2024
    Applicant: NIPPON STEEL Stainless Steel Corporation
    Inventors: Toshiki YOSHIZAWA, Jun-ichi HAMADA
  • Patent number: 11964699
    Abstract: In a metal-fiber reinforced plastic (FRP) composite, the FRP and the metal member are bonded together, so internal stress (thermal stress) is generated due to the misfit of coefficients of thermal expansion of the metal member and the FRP. Not only does the binder layer peel off and the mechanical properties of the FRP cannot be obtained, but also defects in appearance (surface strain) occur. Therefore, the technical problem is to secure the mechanical properties as a composite while easing the internal stress and keeping surface strain from being generated. The metal-fiber reinforced plastic (FRP) composite according to the present invention solves the technical problem by sandwiching an FRP between two metal members and not having at least one of the metal members joined (bonded) with the FRP. Further, it is possible to arrange an intermediate member between the other metal member and the FRP and sandwich the FRP between the two metal members through the intermediate member.
    Type: Grant
    Filed: October 2, 2020
    Date of Patent: April 23, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Masaharu Ibaragi, Noriyuki Negi
  • Patent number: 11965224
    Abstract: This steel sheet for a can is a steel sheet for a can containing, by mass %, C: 0.010% to 0.050%, Si: 0.020% or less, Mn: 0.10% to 0.60%, P: 0.020% or less, S: 0.020% or less, Al: 0.050% or less, N: 0.0100% or less, Nb: 0% to 0.03%, Ti: 0% to 0.03%, B: 0% to 0.0020%, and a remainder including Fe and unavoidable impurities, in which, when the number of carbides having an equivalent circle diameter of 2 ?m or more and 5 ?m or less is indicated by a, and the number of carbides having an equivalent circle diameter of 0.1 ?m or more and less than 2 ?m is indicated by b, a/b satisfies a range of the following formula (1), a fracture strain is 1.6 or more, and a sheet thickness is 0.10 to 0.30 mm a/b<0.12??. . . (1).
    Type: Grant
    Filed: February 17, 2020
    Date of Patent: April 23, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Toshiki Nonaka, Toru Yonebayashi
  • Patent number: 11965232
    Abstract: The seamless steel pipe according to the present disclosure includes a chemical composition consisting of, in mass %, C: 0.030% or less, Si: 1.00% or less, Mn: 1.00% or less, P: 0.030% or less, S: 0.0050% or less, Al: 0.001 to 0.100%, N: 0.0500% or less, O: 0.050% or less, Ni: 3.00 to 6.50%, Cr: more than 10.00 to 13.40%, Mo: 0.50 to 4.00%, V: 0.01 to 1.00%, Ti: 0.010 to 0.300%, and Co: 0.010 to 0.300%, with the balance being Fe and impurities, and satisfying Formula (1), and a microstructure containing, in volume ratio, 80.0% or more of martensite, wherein a depassivation pH of an inner surface is 3.50 or less. Cr+2.0Mo+0.5Ni+0.5Co?16.
    Type: Grant
    Filed: October 1, 2019
    Date of Patent: April 23, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kyohei Kanki, Masayuki Sagara, Yusaku Tomio
  • Patent number: 11965231
    Abstract: The steel material includes a chemical composition containing, in mass %, C: 0.15 to 0.45%, Si: 0.50% or less, Mn: 0.20 to 0.60%, P: 0.015% or less, S: 0.005% or less, Cr: 0.80 to 1.50%, Mo: 0.17 to 0.30%, V: 0.24 to 0.40%, Al: 0.005 to 0.100%, N: 0.0300% or less, O: 0.0015% or less, and the balance being Fe and impurities, and satisfying Formula (1) to Formula (4) described in Embodiment, wherein, in its microstructure, a total area fraction of ferrite and pearlite is 10.0% or more, and a proportion of a content of V (mass %) in electrolytic extraction residue to the content of V (mass %) in the chemical composition is 10.0% or less.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: April 23, 2024
    Assignees: NIPPON STEEL CORPORATION, JTEKT CORPORATION
    Inventors: Yutaka Neishi, Tomohiro Yamashita, Daisuke Hirakami, Takahisa Suzuki, Tatsuya Koyama, Takashi Sada, Kohei Kanetani