Patents by Inventor Masahiro Nakata

Masahiro Nakata 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).

  • Patent number: 11364707
    Abstract: To solve the problem about the difference in temperature increasing rate between an overlapped part and a one-sheet part so as to further improve the corrosion resistance of plating after hot stamping.
    Type: Grant
    Filed: April 5, 2019
    Date of Patent: June 21, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Soshi Fujita, Yuki Suzuki, Masahiro Fuda, Jun Maki, Hideaki Irikawa, Masahiro Nakata
  • Patent number: 11332803
    Abstract: A high-strength hot-dip galvanized steel sheet contains predetermined amounts of C, Si, Mn, P, S, N, O, sol. Al, Ti, and B, 0.1 to 1.5 mass % of Cr+2×Mo, and a balance in a form of Fe and inevitable impurities. A steel structure includes, in area %, ferrite: 1 to 50%, martensite: 20 to 70%, residual austenite: 0 to 5%, pearlite: 0 to 5%, MA and cementite having 0.2 ?m or more grain size: 0 to 5% in total, and a balance in a form of bainite. A number density of MA or cementite having 0.2 ?m or more grain size and isolated in ferrite or bainite grains is 100 pcs/1000 ?m2 or less, and an average hardness of martensite is in a range from 330 to 500 Hv.
    Type: Grant
    Filed: March 22, 2018
    Date of Patent: May 17, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takafumi Yokoyama, Yuji Yamaguchi, Masahiro Nakata, Kunio Hayashi, Satoshi Uchida, Takuma Kawanaka
  • Patent number: 11236412
    Abstract: A steel sheet has a specific chemical composition and has a structure represented by, by area ratio, ferrite: 30 to 95%, and bainite: 5 to 70%. When a region that is surrounded by a grain boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 ?m or more is defined as a crystal grain, the proportion of crystal grains each having an intragranular misorientation of 5 to 14° to all crystal grains is 20 to 100% by area ratio. An average aspect ratio of ellipses equivalent to the crystal grains is 5 or less. An average distribution density of the total of Ti-based carbides and Nb-based carbides each having a grain size of 20 nm or more on ferrite grain boundaries is 10 carbides/?m or less.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: February 1, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kohichi Sano, Makoto Uno, Ryoichi Nishiyama, Yuji Yamaguchi, Natsuko Sugiura, Masahiro Nakata
  • Patent number: 11230755
    Abstract: A steel sheet has a specific chemical composition and has a structure represented by, by area ratio, ferrite: 0 to 30%, and bainite: 70 to 100%. When a region that is surrounded by a grain boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 ?m or more is defined as a crystal grain, the proportion of crystal grains each having an intragranular misorientation of 5 to 14° to all crystal grains is 20 to 100% by area ratio. A grain boundary number density of solid-solution C or a grain boundary number density of the total of solid-solution C and solid-solution B is 1 piece/nm2 or more and 4.5 pieces/nm2 or less. An average grain size of cementite precipitated at grain boundaries is 2 ?m or less.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: January 25, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kohichi Sano, Makoto Uno, Ryoichi Nishiyama, Yuji Yamaguchi, Natsuko Sugiura, Masahiro Nakata
  • Patent number: 11142618
    Abstract: A biaxially stretched polypropylene film including a polypropylene resin and satisfying the following: (a) the crystallite size Sa, which is determined using the Scherrer equation from the full width at half maximum of the ?-crystal (040) plane reflection peak as measured by wide-angle x-ray diffraction after treatment for 200 hours at 105° C., is not more than 12.9 nm; and (b) the planar orientation coefficient ?Pa, which is calculated from the birefringence values ?Nyz and ?Nxz with respect to the thickness direction as determined by optical birefringence measurement after treatment for 200 hours at 105° C., is at least 0.013 (?Pa=(?Nyz+?Nxz)/2).
    Type: Grant
    Filed: September 22, 2017
    Date of Patent: October 12, 2021
    Assignee: Oji Holdings Corporation
    Inventors: Takeshi Tominaga, Michiko Sueyoshi, Yoshimune Okuyama, Masahiro Nakata, Tadakazu Ishiwata
  • Patent number: 11084126
    Abstract: A laser welding method includes: forming a melted section in which plural metallic workpieces within a weld region are melted by projecting a first laser beam onto said weld region with parts of the workpieces being set as the weld region when the workpieces are welded; and projecting a second laser beam while the melted section is being solidified or after a solidified section in which the melted section is solidified is formed such that the second laser beam circles around center of the melted section or the solidified section from an irradiation start position deviated from said center toward said center or such that the second laser beam is focused to the center of the melted section or the solidified section from an irradiation start region that includes the center and a periphery thereof.
    Type: Grant
    Filed: October 18, 2018
    Date of Patent: August 10, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kohei Hisada, Atsushi Kawakita, Masahiro Nakata
  • Publication number: 20210230712
    Abstract: A zinc-plated steel sheet of an aspect of the present invention includes a steel sheet having a predetermined chemical composition and a zinc-plated layer. In the steel sheet, steel microstructures in a range of ? thickness to ? thickness, having the center at ¼ thickness from a steel sheet surface, include, by vol %, ferrite: 0% to 10%, bainite: 0% to 20%, tempered martensite: 70% or more, fresh martensite: 0% to 10%, retained austenite: 0% to 10%, and pearlite: 0% to 5%. In the zinc-plated steel sheet, the amount of hydrogen emitted when the steel sheet is heated to 200° C. from a room temperature after removal of the zinc-plated layer is 0.40 ppm or less per mass of the steel sheet, the tensile strength is 1470 MPa or more, and no cracking occurs in a U-shape bending test where a stress equivalent to 1000 MPa is applied for 24 hours.
    Type: Application
    Filed: April 26, 2019
    Publication date: July 29, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takafumi YOKOYAMA, Kunio HAYASHI, Masahiro NAKATA, Yuji YAMAGUCHI, Satoshi UCHIDA
  • Publication number: 20210197525
    Abstract: To solve the problem about the difference in temperature increasing rate between an overlapped part and a one-sheet part so as to further improve the corrosion resistance of plating after hot stamping.
    Type: Application
    Filed: April 5, 2019
    Publication date: July 1, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Soshi FUJITA, Yuki SUZUKI, Masahiro FUDA, Jun MAKI, Hideaki IRIKAWA, Masahiro NAKATA
  • Publication number: 20210155999
    Abstract: A zinc-plated steel sheet of an aspect of the present invention includes a steel sheet having a predetermined chemical composition and a zinc-plated layer. In the steel sheet, steel microstructures in a range of ? thickness to ? thickness, having the center at ¼ thickness from a steel sheet surface, include, by vol %, ferrite: 0% to 10%, bainite: 0% to 30%, tempered martensite: 50% or more, fresh martensite: 0% to 10%, retained austenite: more than 10% and 30% or less, and pearlite: 0% to 5%. In the zinc-plated steel sheet, the amount of hydrogen emitted when the steel sheet is heated to 200° C. from room temperature after removal of the zinc-plated layer is 0.40 ppm or less per mass of the steel sheet, the tensile strength is 1470 MPa or more, and no cracking occurs in a U-shape bending test where a stress equivalent to 1000 MPa is applied for 24 hours.
    Type: Application
    Filed: April 26, 2019
    Publication date: May 27, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takafumi YOKOYAMA, Kunio HAYASHI, Masahiro NAKATA, Yuji YAMAGUCHI, Satoshi UCHIDA
  • Publication number: 20210134531
    Abstract: In a metallized film 1, n electrode portions 20, which are metal deposition portions, are formed in parallel on one surface of a dielectric film 2 having a film width corresponding to n capacitor elements, n being an even number of 2 or more. Each electrode portion 20 is provided with a plurality of inclined margins 31 and 32, which are non-metal deposition portions extending at an angle with respect to a film width direction, at a regular interval in a film length direction. Across a center line Lc virtually extending in the film length direction at the center in the film width direction, the inclined margins 31 of the electrode portion 20 located on one side in the film width direction, and the inclined margins 32 of the electrode portion 20 located on the other side in the film width direction are inclined in opposite directions so as to be line-symmetric with respect to the center line Lc.
    Type: Application
    Filed: August 14, 2018
    Publication date: May 6, 2021
    Applicant: OJI HOLDINGS CORPORATION
    Inventors: Kazuyuki HIATE, Akihiro KAKEHI, Katsuyuki MORITAKA, Yoshikazu FUJISHIRO, Masahiro NAKATA
  • Publication number: 20210123122
    Abstract: This steel sheet has a predetermined chemical composition, in which a steel structure of an inside of the steel sheet contains, by volume fraction, soft ferrite: 0% to 30%, retained austenite: 3% to 40%, fresh martensite: 0% to 30%, a sum of pearlite and cementite: 0% to 10%, and a remainder includes hard ferrite, in the inside of the steel sheet, a number proportion of the retained austenite having an aspect ratio of 2.0 or more in the total retained austenite is 50% or more, a soft layer having a thickness of 1 to 100 ?m from a surface in a sheet thickness direction is present, in ferrite contained in the soft layer, a volume fraction of grains having an aspect ratio of less than 3.0 is 50% or more, the volume fraction of retained austenite in the soft layer is less than 50% of the volume fraction of the retained austenite of the inside of the steel sheet, and a peak of an emission intensity at a wavelength indicating Si appears in a range of more than 0.2 ?m and 5.0 ?m or less from the surface.
    Type: Application
    Filed: March 30, 2018
    Publication date: April 29, 2021
    Applicant: Nippon Steel Corporation
    Inventors: Takafumi YOKOYAMA, Kohichi SANO, Riki OKAMOTO, Hiroyuki KAWATA, Eisaku SAKURADA, Yuji YAMAGUCHI, Kazuki SHIOKAWA, Yuichi NAKAHIRA, Kohei UEDA, Masahiro NAKATA, Satoshi UCHIDA
  • Publication number: 20210095356
    Abstract: A steel sheet according to an aspect of the present invention has a predetermined chemical composition, in which a steel structure of an inside of the steel sheet contains, by volume fraction, soft ferrite: 0% to 30%, retained austenite: 3% to 40%, fresh martensite: 0% to 30%, a sum of pearlite and cementite: 0% to 10%, and a remainder including hard ferrite, in the inside of the steel sheet, a number proportion of the retained austenite having an aspect ratio of 2.0 or more in the total retained austenite is 50% or more, a soft layer having a thickness of 1 ?m to 100 ?m from the surface is present in a sheet thickness direction, among ferrite contained in the soft layer, a volume fraction of grains having an aspect ratio of less than 3.0 is 50% or more, a volume fraction of retained austenite in the soft layer is 50% or more of the volume fraction of the retained austenite of the inside of the steel sheet, and a peak of an emission intensity at a wavelength indicating Si appears in a range of more than 0.
    Type: Application
    Filed: March 30, 2018
    Publication date: April 1, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takafumi YOKOYAMA, Kohichi SANO, Riki OKAMOTO, Hiroyuki KAWATA, Eisaku SAKURADA, Yuji YAMAGUCHI, Kazuki SHIOKAWA, Yuichi NAKAHIRA, Kohei UEDA, Masahiro NAKATA, Satoshi UCHIDA
  • Patent number: 10910164
    Abstract: The present invention relates to a biaxially stretched polypropylene film for capacitor. The biaxially stretched polypropylene film for capacitor of the present invention can suppress an increase in tan ? and a decrease in the electrostatic capacitance even when the capacitor is used at a high voltage and an elevated temperature for a long duration.
    Type: Grant
    Filed: March 31, 2016
    Date of Patent: February 2, 2021
    Assignee: OJI HOLDINGS CORPORATION
    Inventors: Yoshimune Okuyama, Yoshikazu Fujishiro, Masahiro Nakata, Tadakazu Ishiwata, Akihiro Kakehi
  • Patent number: 10889879
    Abstract: A steel sheet having a specific chemical composition and structure represented by, by area ratio, ferrite: 5 to 95%, and bainite: 5 to 95%. The proportion of crystal grains having an intragranular misorientation of 5 to 14° to all crystal grains is 20 to 100% by area ratio. Hard crystal grains A in which precipitates or clusters with a maximum diameter of 8 nm or less are dispersed in the crystal grains with a number density of 1×1016 to 1×1019 pieces/cm3. Soft crystal grains B in which precipitates or clusters with a maximum diameter of 8 nm or less are dispersed in the crystal grains with a number density of 1×1015 pieces/cm3 or less are contained. The volume % of the hard crystal grains A/(the volume % of the hard crystal grains A+the volume % of the soft crystal grains B) is 0.1 to 0.9.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: January 12, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kohichi Sano, Makoto Uno, Ryoichi Nishiyama, Yuji Yamaguchi, Natsuko Sugiura, Masahiro Nakata
  • Publication number: 20200377706
    Abstract: A polypropylene film which is capable of suppressing blocking in a rolled polypropylene film. The polypropylene film has a first surface and a second surface, contains a polypropylene resin as a main component, and is configured such that: the Svk value (SvkA) of the first surface is 0.005 ?m or more and 0.030 ?m or less; the Spk value (SpkA) of the first surface is more than 0.035 ?m and 0.080 ?m or less; the Svk value (SvkB) of the second surface is 0.005 ?m or more and 0.030 ?m or less; and the Spk value (SpkB) of the second surface is 0.015 ?m or more and 0.035 ?m or less.
    Type: Application
    Filed: December 26, 2018
    Publication date: December 3, 2020
    Inventors: Tatsuji ISHIDA, Yoshimune OKUYAMA, Masahiro NAKATA, Tadakazu ISHIWATA
  • Patent number: 10799930
    Abstract: This press forming method is a press forming method of manufacturing a press-formed article from a workpiece sheet using a press forming apparatus including a punch, a die, a punch pad, and a die pad, in which, when the workpiece sheet is clamped between the die and the punch, a surface of the workpiece sheet on a die side in a section between a point in contact with a die bottom end shoulder portion and a point in contact with the die pad is in non-contact with the die and the die pad, and an end surface of a punch side blank holding surface adjacent to a punch shoulder portion is flush with the punch shoulder portion or located on a more inner side of the punch than the punch shoulder portion.
    Type: Grant
    Filed: March 2, 2016
    Date of Patent: October 13, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Toshiya Suzuki, Yoshiaki Nakazawa, Masahiro Nakata
  • Patent number: 10787142
    Abstract: This supporting structure for an underrun protector includes a stay body that connects a beam and a frame to each other; a stay reinforcing body that reinforces the stay body from an outside in a vehicle width direction; and a gusset provided between the stay reinforcing body and the beam. A stay body web face of the stay body is provided with an opening part. A pair of wall face parts provided to extend outward in the vehicle width direction from both ends of the opening part in a vehicle forward-rearward direction is provided so as to face each other. Each of the wall face parts is provided at a height corresponding to an installation position of the gusset and abuts against an inner surface of the stay reinforcing body in the vehicle width direction.
    Type: Grant
    Filed: August 24, 2017
    Date of Patent: September 29, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yutaka Mikazuki, Eiji Isogai, Masahiro Nakata, Kenji Yamamoto
  • Patent number: 10759929
    Abstract: A main object is to provide a biaxially stretched polypropylene film for capacitors that has high voltage resistance at high temperatures and excellent dielectric breakdown properties and that can be formed into an ultrathin film. Furthermore, a capacitor obtained by using the biaxially stretched polypropylene film for capacitors described above is provided. The biaxially stretched polypropylene film for capacitors, includes a polypropylene resin, and the film has a spacing value of (040) face of ?-crystal measured by X-ray diffraction of 0.525 to 0.530 nm.
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: September 1, 2020
    Assignee: OJI HOLDINGS CORPORATION
    Inventors: Toshiaki Taniike, Minoru Terano, Ikki Katada, Tadakazu Ishiwata, Masahiro Nakata
  • Publication number: 20200165497
    Abstract: Provided is a double-sided adhesive tape or sheet which is light-weight and has excellent strength and insulating properties even when the thickness of the tape or sheet is small. This double-sided adhesive tape or sheet comprises a laminate including a support and two adhesive agent layers formed on opposite surfaces of the support, wherein the support contains a polypropylene resin, the adhesive agent layers contain an acrylic polymer, the laminate has a total thickness (Ds) of 4-15 ?m, the value of the ratio Dp/Ds of the thickness (Dp) of the support to the total thickness (Ds) of the laminate is 0.15-0.6, and the laminate has a density of 0.90-1.10 g/cm3.
    Type: Application
    Filed: July 13, 2018
    Publication date: May 28, 2020
    Inventors: Kazuo IKEDA, Masahiro NAKATA, Minoru INOUE, Takamichi YAMAGUCHI, Tohru MURAI, Kenji YANAGISAWA
  • Publication number: 20200115771
    Abstract: A high-strength hot-dip galvanized steel sheet contains predetermined amounts of C, Si, Mn, P, S, N, O, sol. Al, Ti, and B, 0.1 to 1.5 mass % of Cr+2×Mo, and a balance in a form of Fe and inevitable impurities. A steel structure includes, in area %, ferrite: 1 to 50%, martensite: 20 to 70%, residual austenite: 0 to 5%, pearlite: 0 to 5%, MA and cementite having 0.2 ?m or more grain size: 0 to 5% in total, and a balance in a form of bainite. A number density of MA or cementite having 0.2 ?m or more grain size and isolated in ferrite or bainite grains is 100 pcs/1000 ?m2 or less, and an average hardness of martensite is in a range from 330 to 500 Hv.
    Type: Application
    Filed: March 22, 2018
    Publication date: April 16, 2020
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takafumi YOKOYAMA, Yuji YAMAGUCHI, Masahiro NAKATA, Kunio HAYASHI, Satoshi UCHIDA, Takuma KAWANAKA