Patents Assigned to JFE Steel Corporation
  • Publication number: 20250053706
    Abstract: A press forming analysis method includes: a first blank generation step of generating a standard waveform blank model; a first shape acquisition step of acquiring a first shape, which is a shape of press-formed part using standard waveform blank; a second blank generation step of generating a cycle deviation waveform blank model; a second shape acquisition step of acquiring a second shape, which is a shape of press-formed part using cycle deviation waveform blank; and a deviation amount acquisition step of obtaining a portion where both of the shapes deviate from each other and a deviation amount by comparing the first shape with the second shape.
    Type: Application
    Filed: November 9, 2022
    Publication date: February 13, 2025
    Applicant: JFE STEEL CORPORATION
    Inventors: Takeshi OGAWA, Satoshi SUMIKAWA, Yuji YAMASAKI, Toyohisa SHINMIYA
  • Publication number: 20250052672
    Abstract: A method for quantifying carbon in carbides that allows highly precise and simple quantification of carbon in carbides. The method for quantifying carbon in the carbides includes a combustion process in which the carbides are heated together with a composite member in the presence of oxygen to oxidize the carbon in the carbides to carbon monoxide and/or carbon dioxide, and a quantification process of quantifying the carbon monoxide and/or the carbon dioxide. The composite member includes two or more metal members that have main components that are different from each other.
    Type: Application
    Filed: December 19, 2022
    Publication date: February 13, 2025
    Applicant: JFE STEEL CORPORATION
    Inventor: Seiya SUGAWARA
  • Publication number: 20250050403
    Abstract: A method of evaluating a peripheral shape of a press formed part includes: acquiring, as a peripheral shape of an actual press formed part, a peripheral shape of a press formed part workpiece bottom dead center shape model acquired by mechanical analysis in a process of sandwiching the actual press formed part that is actually press-formed and is spring-backed up to a forming bottom dead center, obtaining a press formed part analysis model by elastoplastic mechanical analysis in a process of press forming the actual press formed part, acquiring a peripheral shape at the forming bottom dead center of the press formed part analysis model, and comparing the peripheral shapes of the actual press formed part and the press formed part analysis model and evaluating each of the peripheral shapes.
    Type: Application
    Filed: December 13, 2022
    Publication date: February 13, 2025
    Applicant: JFE STEEL CORPORATION
    Inventors: Masaki URABE, Akinobu ISHIWATARI
  • Publication number: 20250051873
    Abstract: A method for producing Cu—Sn-containing steel includes a hot heating step of attaching a flux to a surface of a Cu—Sn-containing cast steel in such an amount that the mass per unit area is 50 g/m2 or more and 5000 g/m2 or less, and heating the Cu—Sn-containing cast steel at a temperature of 1000° C. or above and 1400° C. or below, the flux including at least any of B2O3, P2O5, K2O, PbO, Na2O—FeO, Na2O—SiO2, Na2O—TiO2, and Li2O—SiO2 components and being such that the liquid phase ratio at 1000° C. is 10 mass % or more; and a hot working step of hot working the Cu—Sn-containing cast steel.
    Type: Application
    Filed: December 5, 2022
    Publication date: February 13, 2025
    Applicant: JFE Steel Corporation
    Inventors: Yuta SAKURAI, Tomoya ODAGAKI, Kenji TSUZUMI, Akitoshi MATSUI, Tetsuo MOCHIDA, Naoki KIKUCHI
  • Patent number: 12221705
    Abstract: Provided is an alloyed galvanized steel sheet with excellent resistance to cracking in resistance welding at a welded portion, even if crystal orientations of an Fe-based electroplating layer and a cold-rolled steel sheet are integrated at a high ratio at the interface between the Fe-based electroplating layer and the cold-rolled steel sheet. The alloyed galvanized steel sheet has a Si-containing cold-rolled steel sheet containing Si in an amount of 0.1 mass % to 3.0 mass %; an Fe-based electroplating layer formed on at least one surface of the Si-containing cold-rolled steel sheet with a coating weight per surface exceeding 20.0 g/m2, and an alloyed galvanized layer formed on the Fe-based electroplating layer, where crystal orientations of the Fe-based electroplating layer and the Si-containing cold-rolled steel sheet are integrated at a ratio of more than 50% at the interface between the Fe-based electroplating layer and the Si-containing cold-rolled steel sheet.
    Type: Grant
    Filed: November 5, 2021
    Date of Patent: February 11, 2025
    Assignee: JFE STEEL CORPORATION
    Inventors: Shunsuke Yamamoto, Katsutoshi Takashima, Mai Aoyama, Yusuke Okumura, Tomomi Kanazawa, Katsuya Hoshino, Hiroshi Matsuda, Ei Okumura, Yoichi Makimizu, Masaki Koba
  • Patent number: 12221668
    Abstract: Provided is a high strength steel sheet that has a predetermined chemical composition and is manufactured under optimum conditions, the high strength steel sheet having a steel microstructure including, by area, ferrite: 30% or more and 80% or less, martensite: 5% or more and 35% or less, and retained austenite: 8% or more, wherein the quotient of the area fraction of grains of the retained austenite, the grains having an aspect ratio of 2.0 or more and a minor axis length of 1 ?m or less, divided by the total area fraction of the retained austenite is 0.3 or more, wherein the quotient of the average Mn content (mass %) in the retained austenite divided by the average Mn content (mass %) in the ferrite is 1.5 or more.
    Type: Grant
    Filed: October 8, 2020
    Date of Patent: February 11, 2025
    Assignee: JFE Steel Corporation
    Inventors: Kazuki Endoh, Yoshiyasu Kawasaki, Yuki Toji
  • Patent number: 12221663
    Abstract: The invention is intended to provide a martensitic stainless steel seamless pipe for oil country tubular goods having a yield stress of 758 MPa or more, and excellent sulfide stress corrosion cracking resistance. A method for manufacturing such a martensitic stainless steel seamless pipe is also provided. The martensitic stainless steel seamless pipe for oil country tubular goods has a composition that contains, in mass %, C: 0.010% or more, Si: 0.5% or less, Mn: 0.05 to 0.50%, P: 0.030% or less, S: 0.005% or less, Ni: 4.6 to 8.0%, Cr: 10.0 to 14.0%, Mo: 1.0 to 2.7%, Al: 0.1% or less, V: 0.005 to 0.2%, N: 0.1% or less, Ti: 0.010 to 0.054%, Cu: 0.01 to 1.0%, and Co: 0.01 to 1.0%. C, Mn, Cr, Cu, Ni, Mo, W, N, and Ti satisfy the predetermined relations, and the balance is Fe and incidental impurities. The martensitic stainless steel seamless pipe has a yield stress of 758 MPa or more.
    Type: Grant
    Filed: April 25, 2019
    Date of Patent: February 11, 2025
    Assignee: JFE STEEL CORPORATION
    Inventors: Mami Endo, Yuichi Kamo, Masao Yuga
  • Patent number: 12221660
    Abstract: Provided is a method for producing a rail, with which the sweep in the height direction of a rail before straightening can be suppressed when producing standard rails specified in JIS E 1101. The method includes subjecting a bloom having a chemical composition containing, in mass %, C: 0.60% or more and 0.85% or less, Si: 0.10% or more and 1.00% or less, and Mn: 0.10% or more and 1.30% or less, with the balance being Fe and inevitable impurities, to hot rolling to obtain a rail, subjecting the rail to accelerated cooling under conditions where a cooling start temperature T1 of rail head is 750° C. or higher and 850° C. or lower, a cooling stop temperature T2 of rail head is higher than 700° C., and T1?T2 is 20° C. or more, and then allowing the rail to be naturally cooled.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: February 11, 2025
    Assignee: JFE STEEL CORPORATION
    Inventors: Minoru Honjo, Mineyasu Takemasa
  • Patent number: 12222069
    Abstract: A high-pressure hydrogen tank includes a metal circular cylinder configured to store high-pressure hydrogen therein, a cap part configured to cover each of opposite end portions of the metal circular cylinder, an outer cylinder surrounding an outer periphery of a circular-cylindrical portion of the metal circular cylinder, and a fastening part configured to fix the cap part to the outer cylinder.
    Type: Grant
    Filed: November 11, 2019
    Date of Patent: February 11, 2025
    Assignee: JFE STEEL CORPORATION
    Inventors: Toshio Takano, Hiroshi Okano, Akihide Nagao, Nobuyuki Ishikawa, Kazuki Matsubara
  • Publication number: 20250043398
    Abstract: A non-oriented electrical steel sheet includes, by mass %, C: 0.010% or less, Si: 1.0% or more and 5.0% or less, Mn: 0.05% or more and 5.0% or less, P: 0.1% or less, S: 0.01% or less, Al: 3.0% or less, N: 0.005% or less, and the balance being Fe and inevitable impurities, wherein an average crystal grain size is 60 ?m or more and 200 ?m or less, and a sum SA of area ratios of crystal grains with <100> oriented in a rolling direction or a direction perpendicular to the rolling direction and a sum SB of area ratios of crystal grains with <111> oriented in the rolling direction or the direction perpendicular to the rolling direction satisfy SA?SB?0.
    Type: Application
    Filed: December 12, 2022
    Publication date: February 6, 2025
    Applicant: JFE Steel Corporation
    Inventors: Takaaki TANAKA, Tomoyuki OKUBO
  • Publication number: 20250044082
    Abstract: A press forming analysis method includes: (a) acquiring a shape of a standard press-formed part; (b) generating a waveform blank model; (c) acquiring a shape of a waveform blank press-formed part; (d) comparing the shape of the standard press-formed part and the shape of the waveform blank press-formed part, and obtaining a deviation amount of shape change; (e) generating one or more types of cycle deviation waveform blank models; (f) acquiring a shape of a cycle deviation waveform blank press-formed part; (g) comparing the shape of the standard press-formed part with one or more types of the shape of the cycle deviation waveform blank press-formed part, and obtaining a deviation amount of shape change; and (h) identifying, as a portion requiring countermeasures, a portion having a deviation amount of shape change exceeding a threshold among the deviation amounts of shape change obtained in (d) and (g).
    Type: Application
    Filed: November 8, 2022
    Publication date: February 6, 2025
    Applicant: JFE STEEL CORPORATION
    Inventors: Takeshi OGAWA, Satoshi SUMIKAWA, Toyohisa SHINMIYA, Yuji YAMASAKI
  • Publication number: 20250041924
    Abstract: A fatigue crack growth suppressing method for a bent portion of a metal sheet suppresses growth of a fatigue crack in the bent portion obtained by bending the metal sheet. The fatigue crack growth suppressing method includes generating a compressive residual stress by applying plastic strain at least within a range from a bending start point to a bending end point on an inside of a bend of the bent portion, at an interval of less than a sheet thickness of the metal sheet in a valley line direction of the bent portion, in a direction orthogonal to the valley line direction.
    Type: Application
    Filed: August 18, 2022
    Publication date: February 6, 2025
    Applicant: JFE STEEL CORPORATION
    Inventor: Naoki YAMAGUCHI
  • Patent number: 12215405
    Abstract: Provided is a hot-pressed member that combines both high strength of 1850 MPa or more in TS and excellent delayed fracture resistance. A hot-pressed member comprises: a predetermined chemical composition; a microstructure in which a prior austenite average grain size is 8 ?m or less, a volume fraction of martensite is 95% or more, and a volume fraction of granular carbide of 0.1 ?m or more in grain size is 0.10% to 4.0%; a Ni diffusion region of 2.0 ?m or more in a depth direction in a surface layer; and a tensile strength of 1850 MPa or more.
    Type: Grant
    Filed: January 17, 2020
    Date of Patent: February 4, 2025
    Assignee: JFE STEEL CORPORATION
    Inventors: Katsutoshi Takashima, Minoru Tanaka, Yoshie Obata, Michitaka Sakurai
  • Patent number: 12214399
    Abstract: Warpage or torsion in a longitudinal direction is suppressed when an elongated curved component is manufactured by press forming. A method for manufacturing a pressed component includes a first step of press forming a metal sheet in a desired component shape using a first die, and a second step of press forming a formed product using a second die after the first step. In the second step, a cross section of a bent part and a vertical wall part are controlled to be opened depending on warpage at longitudinal end portions of the component by elastic recovery due to release from the first die, thereby suppressing the warpage.
    Type: Grant
    Filed: February 14, 2020
    Date of Patent: February 4, 2025
    Assignee: JFE STEEL CORPORATION
    Inventors: Hiroto Miyake, Toyohisa Shinmiya, Yuji Yamasaki
  • Publication number: 20250033114
    Abstract: Provided is an iron-based mixed powder for powder metallurgy that has excellent compressibility and, even in a typical production process with a compacting pressure of less than 600 MPa, enables production of a sintered body having a tensile strength of 1200 MPa or more and excellent impact resistance. An iron-based mixed powder for powder metallurgy consists of: a partially diffusion-alloyed steel powder comprising an iron-based powder and Mo diffusionally adhered to a surface of the iron-based powder; and an alloying metal powder. The iron-based powder has a certain chemical composition, the partially diffusion-alloyed steel powder has a Mo content of 0.20 mass % or more and 1.5 mass % or less, and an apparent density of 2.8 g/cm3 or more and 3.6 g/cm3 or less, and the alloying metal powder contains at least one of a Cu powder and a Ni powder with a certain apparent density in a certain amount.
    Type: Application
    Filed: October 27, 2022
    Publication date: January 30, 2025
    Applicant: JFE STEEL CORPORATION
    Inventors: Kohsuke ASHIZUKA, Shigeru UNAMI
  • Publication number: 20250034739
    Abstract: Provided is a surface-treated steel sheet that can be produced without using hexavalent chromium and is excellent in adhesion to BPA-free paint and BPA-free painting corrosion resistance. A surface-treated steel sheet comprises: a steel sheet; a metallic Cr layer disposed on a surface of the steel sheet on at least one side; and a Cr oxide layer disposed on the metallic Cr layer, wherein a contact angle of ethylene glycol is 50° or less, and a total atomic ratio of K, Na, Mg, and Ca adsorbed on a surface of the surface-treated steel sheet on the at least one side to Cr is 5.0% or less.
    Type: Application
    Filed: February 20, 2023
    Publication date: January 30, 2025
    Applicant: JFE STEEL CORPORATION
    Inventors: Takashi UENO, Yusuke NAKAGAWA
  • Publication number: 20250034685
    Abstract: Provided is a non-oriented electrical steel sheet having such a low Al concentration so that it is excellent in terms of the recycling efficiency of scrap iron and having a high magnetic flux density and low iron loss. The non-oriented electrical steel sheet according to the present invention has a chemical composition containing C; 0.0050 mass % or less, Si; 1.5 mass % to 5.0 mass %, Mn; 0.2 mass % to 3.0 mass %, sol·Al; 0.0030 mass % or less, P; 0.2 mass % or less, S; 0.0050 mass % or less, N; 0.0040 mass % or less, T·Ca; 0.0010 mass % to 0.0080 mass %, T·O; 0.0100 mass % or less, REM; 0.0001 mass % to 0.0050 mass %, and a balance of Fe and inevitable impurities, in which a value of a mass-related fractional expression ((T·Ca+REM)/(T·O+S)), which is a relational expression for the masses of the four constituents described above, that is, T·Ca, REM, T·O, and S, is 0.4 or more.
    Type: Application
    Filed: October 11, 2024
    Publication date: January 30, 2025
    Applicant: JFE Steel Corporation
    Inventors: Akifumi Harada, Akitoshi Matsui, Yoshihiko Oda, Tomoyuki Okubo, Masanori Uesaka
  • Publication number: 20250037921
    Abstract: A laminated core is disclosed and includes a stack of pieces of an electrical steel sheet that have a predetermined shape resulting from processing. The electrical steel sheet includes an insulating coating on a surface. A frequency of formation of cracks propagating through the insulating coating in a region extending 100 ?m toward a middle of the electrical steel sheet from a processed edge of the electrical steel sheet is less than or equal to 3.0 times the frequency of formation of cracks propagating through the insulating coating in a region extending toward the middle of the electrical steel sheet from a position more than 100 ?m from the processed edge to a position 500 ?m from the processed edge, where the frequency is expressed as a number per mm.
    Type: Application
    Filed: September 22, 2022
    Publication date: January 30, 2025
    Applicant: JFE Steel Corporation
    Inventors: Takeshi OMURA, Yoshihisa ICHIHARA, Souichiro YOSHIZAKI
  • Publication number: 20250034691
    Abstract: A gas wiping nozzle and a method for manufacturing a hot-dip metal-coated steel strip using the gas wiping nozzle. The gas wiping nozzle adjusts the coating weight of a molten metal on the surface of a steel strip pulled up from a molten metal bath. At least the surface of the gas wiping nozzle is made of a ceramic, and the arithmetic mean roughness Ra and the peak count PPI of the gas wiping nozzle satisfy Formula (1): PPI > c ? 1 × Ra + c ? 2 ( 1 ) PPI: peak count (the number of peaks per inch) Ra: arithmetic mean roughness [?m] c1 and c2: determined constants for each ceramic used in the surface of the gas wiping nozzle.
    Type: Application
    Filed: October 11, 2022
    Publication date: January 30, 2025
    Applicant: JFE STEEL CORPORATION
    Inventors: Yu ITO, Hideyuki TAKAHASHI, Kenji YAMASHIRO, Takumi KOYAMA, Yoshihiko KAKU
  • Publication number: 20250034673
    Abstract: An apparatus for manufacturing a steel strip, includes: a first water tank part that stores cooling water for immersing and cooling a steel strip; a water cooling nozzle unit that is provided in the first water tank part and injects cooling water to a surface of the steel strip; a second water tank part connected to the first water tank part through a joining port; an opening and closing door that opens and closes the joining port; and a conveyance control part that conveys the water cooling nozzle unit such that the water cooling nozzle unit passes through the joining port and is positioned at either a cooling water injection position inside the first water tank part or a non-water cooling standby position inside the second water tank part.
    Type: Application
    Filed: July 28, 2022
    Publication date: January 30, 2025
    Applicant: JFE Steel Corporation
    Inventors: Hirokazu KOBAYASHI, Gentaro TAKEDA, Munesuke SUZUKI, Kazuki OKAMOTO, Hidenori SHIMADA