Patents by Inventor Fuminobu MURAKAMI

Fuminobu 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).

  • 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
  • Patent number: 11952641
    Abstract: A non oriented electrical steel sheet consists of a silicon steel sheet and an insulation coating. The silicon steel sheet includes an internally oxidized layer containing SiO2 in a surface thereof, an average thickness of the internally oxidized layer is 0.10 to 5.0 ?m, and a Vickers hardness in the internally oxidized layer is 1.15 to 1.5 times as compared with a Vickers hardness in a thickness central area.
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: April 9, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Masaru Takahashi, Takeru Ichie, Tesshu Murakawa, Shinichi Matsui, Fuminobu Murakami
  • Publication number: 20240093322
    Abstract: A hot rolled steel sheet is for a non oriented electrical steel sheet, wherein vickers hardness at the widthwise edge is 180 Hv or more, a value obtained by subtracting a vickers hardness at the widthwise center from the vickers hardness at the widthwise edge is 10 to 100 Hv, ductile brittle transition temperature at the widthwise edge is 0° C. or less, a value obtained by subtracting the ductile brittle transition temperature at the widthwise edge from a ductile brittle transition temperature at the widthwise center is 10 to 100° C., and a value obtained by subtracting a sheet thickness at the widthwise edge from a sheet thickness at the widthwise center is 50 ?m or less.
    Type: Application
    Filed: February 19, 2021
    Publication date: March 21, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yoshihiro ARITA, Takeru ICHIE, Fuminobu MURAKAMI
  • Publication number: 20230392225
    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: Application
    Filed: March 31, 2022
    Publication date: December 7, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Nobusato MORISHIGE, Takeru ICHIE, Masato YASUDA, Masahide URAGO, Fuminobu MURAKAMI, Daichi HAMADA, Atsushi SHIBAYAMA, Kazumi MIZUKAMI, Daisuke ITABASHI
  • Publication number: 20230063410
    Abstract: A hot-rolled steel sheet for a non-oriented electrical steel sheet according to one aspect of the present invention contains, by mass %, C: 0.0050% or less, Si: 0.5% or more and 3.5% or less, Mn: 0.1% or more and 1.5% or less, Al: 0.1% or more and 1.5% or less, Cu: 0.01% or more and 0.10% or less, Sn: 0.01% or more and 0.20% or less, and a remainder including Fe and impurities, in which the hot-rolled steel sheet has a Cu concentration peak value of 0.12% or more in a range from a surface thereof to a depth of 10 ?m.
    Type: Application
    Filed: February 19, 2021
    Publication date: March 2, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yoshihiro ARITA, Takeru ICHIE, Fuminobu MURAKAMI
  • Patent number: 11421297
    Abstract: A non-oriented electrical steel sheet includes a silicon steel sheet and an insulation coating. When t is a thickness of the silicon steel sheet and when PDR is defined as (PDR=(maximum?minimum)/minimum×100) which indicates a ratio concerned with maximum and minimum of number densities of AlN precipitates in three areas which are 1/10t area, ?t area, and ½t area from a surface of the silicon steel sheet along a thickness direction, the PDR is 50% or less.
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: August 23, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takeru Ichie, Masaru Takahashi, Fuminobu Murakami, Shinichi Matsui, Masahiro Yamamoto
  • Publication number: 20220154304
    Abstract: A non oriented electrical steel sheet consists of a silicon steel sheet and an insulation coating. The silicon steel sheet includes an internally oxidized layer containing SiO2 in a surface thereof, an average thickness of the internally oxidized layer is 0.10 to 5.0 ?m, and a vickers hardness in the internally oxidized layer is 1.15 to 1.5 times as compared with a vickers hardness in a thickness central area.
    Type: Application
    Filed: March 20, 2019
    Publication date: May 19, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Masaru TAKAHASHI, Takeru ICHIE, Tesshu MURAKAWA, Shinichi MATSUI, Fuminobu MURAKAMI
  • Publication number: 20220145418
    Abstract: A non oriented electrical steel sheet consists of a silicon steel sheet and an insulation coating. The silicon steel sheet contains Si, Al, and Mn as chemical composition, and an alignment degree to {5 5 7}<7 14 5> orientation in a central area along a thickness direction of the silicon steel sheet is 12 to 35.
    Type: Application
    Filed: March 20, 2019
    Publication date: May 12, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takeru ICHIE, Masaru TAKAHASHI, Fuminobu MURAKAMI, Shinichi MATSUI, Masahiro YAMAMOTO
  • Publication number: 20200399731
    Abstract: A non-oriented electrical steel sheet includes a silicon steel sheet and an insulation coating. When t is a thickness of the silicon steel sheet and when PDR is defined as (PDR=(maximum?minimum)/minimum×100) which indicates a ratio concerned with maximum and minimum of number densities of AlN precipitates in three areas which are 1/10t area, ?t area, and ½t area from a surface of the silicon steel sheet along a thickness direction, the PDR is 50% or less.
    Type: Application
    Filed: March 20, 2019
    Publication date: December 24, 2020
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takeru ICHIE, Masaru TAKAHASHI, Fuminobu MURAKAMI, Shinichi MATSUI, Masahiro YAMAMOTO