Patents by Inventor Masamitsu KUBOTA

Masamitsu KUBOTA 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: 11866812
    Abstract: A grain oriented electrical steel sheet includes a base steel sheet, an oxide layer, and a tension-insulation coating. When a glow discharge spectroscopy is conducted in a region from a surface of the tension-insulation coating to an inside of the base steel sheet, a sputtering time Fe0.5 at which a Fe emission intensity becomes 0.5 times as compared with a saturation value thereof and a sputtering time Fe0.05 at which a Fe emission intensity becomes 0.05 times as compared with the saturation value satisfy (Fe0.5?Fe0.05)/Fe0.5?0.35. A maximal point of a Cr emission intensity is included between the Fe0.05 and the Fesat. Moreover, a magnetic flux density B8 in a rolling direction of the grain oriented electrical steel sheet is 1.90 T or more.
    Type: Grant
    Filed: February 7, 2020
    Date of Patent: January 9, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Ichiro Tanaka, Takashi Kataoka, Kazutoshi Takeda, Masamitsu Kubota, Hirotoshi Tada
  • Patent number: 11661636
    Abstract: A method for manufacturing a grain-oriented electrical steel sheet according to an aspect of the present invention includes a step of obtaining a hot-rolled steel sheet by carrying out hot rolling on a slab containing a predetermined component composition with a remainder including Fe and impurities, a step of obtaining a hot-rolled annealed sheet by carrying out hot-rolled sheet annealing as necessary, a step of carrying out pickling to obtain a pickled sheet, a step of carrying out cold rolling to obtain a cold-rolled steel sheet, a step of carrying out primary recrystallization annealing, a step of applying an annealing separating agent including MgO to a surface and then carrying out final annealing to obtain a final-annealed sheet, and a step of applying an insulating coating and then carrying out flattening annealing.
    Type: Grant
    Filed: March 19, 2019
    Date of Patent: May 30, 2023
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Nobusato Morishige, Takashi Kataoka, Haruhiko Atsumi, Yasuhiro Mayumi, Toshiya Takechi, Naoto Masumitsu, Tomoya Suenaga, Masamitsu Kubota, Hideyuki Hamamura, Kazuhiko Fukutani
  • Publication number: 20220243315
    Abstract: A grain oriented electrical steel sheet includes a base steel sheet, an oxide layer, and a tension-insulation coating. When a glow discharge spectroscopy is conducted in a region from a surface of the tension-insulation coating to an inside of the base steel sheet, a sputtering time Fe0.5 at which a Fe emission intensity becomes 0.5 times as compared with a saturation value thereof and a sputtering time Fe0.05 at which a Fe emission intensity becomes 0.05 times as compared with the saturation value satisfy 0.01<(Fe0.5?Fe0.05)/Fe0.5<0.35. Moreover, a magnetic flux density B8 in a rolling direction of the grain oriented electrical steel sheet is 1.90 T or more.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 4, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Ichiro TANAKA, Takashi KATAOKA, Kazutoshi TAKEDA, Masamitsu KUBOTA, Hirotoshi TADA
  • Publication number: 20220090242
    Abstract: A grain oriented electrical steel sheet includes a base steel sheet, an oxide layer, and a tension-insulation coating. When a glow discharge spectroscopy is conducted in a region from a surface of the tension-insulation coating to an inside of the base steel sheet, a sputtering time Fe0.5 at which a Fe emission intensity becomes 0.5 times as compared with a saturation value thereof and a sputtering time Fe0.05 at which a Fe emission intensity becomes 0.05 times as compared with the saturation value satisfy (Fe0.5?Fe0.05)/Fe0.5?0.35. A maximal point of a Cr emission intensity is included between the Fe0.05 and the Fesat. Moreover, a magnetic flux density B8 in a rolling direction of the grain oriented electrical steel sheet is 1.90 T or more.
    Type: Application
    Filed: February 7, 2020
    Publication date: March 24, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Ichiro TANAKA, Takashi KATAOKA, Kazutoshi TAKEDA, Masamitsu KUBOTA, Hirotoshi TADA
  • Publication number: 20210017619
    Abstract: A method for manufacturing a grain-oriented electrical steel sheet according to an aspect of the present invention includes a step of obtaining a hot-rolled steel sheet by carrying out hot rolling on a slab containing a predetermined component composition with a remainder including Fe and impurities, a step of obtaining a hot-rolled annealed sheet by carrying out hot-rolled sheet annealing as necessary, a step of carrying out pickling to obtain a pickled sheet, a step of carrying out cold rolling to obtain a cold-rolled steel sheet, a step of carrying out primary recrystallization annealing, a step of applying an annealing separating agent including MgO to a surface and then carrying out final annealing to obtain a final-annealed sheet, and a step of applying an insulating coating and then carrying out flattening annealing.
    Type: Application
    Filed: March 19, 2019
    Publication date: January 21, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Nobusato MORISHIGE, Takashi KATAOKA, Haruhiko ATSUMI, Yasuhiro MAYUMI, Toshiya TAKECHI, Naoto MASUMITSU, Tomoya SUENAGA, Masamitsu KUBOTA, Hideyuki HAMAMURA, Kazuhiko FUKUTANI