公开(公告)号：US11952641B2

公开(公告)日：2024-04-09

申请号：US17437703

申请日：2019-03-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Masaru Takahashi ,  Takeru Ichie ,  Tesshu Murakawa ,  Shinichi Matsui ,  Fuminobu Murakami

IPC: C22C38/00 ,  C21D6/00 ,  C21D8/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  C23G1/08 ,  H01F1/147

CPC classification number: C21D9/46 ,  C21D6/005 ,  C21D6/008 ,  C21D8/005 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1283 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  C23G1/08 ,  H01F1/147 ,  C22C2202/02

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 μm, 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.

公开(公告)号：US12110569B2

公开(公告)日：2024-10-08

申请号：US17437726

申请日：2019-03-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Takeru Ichie ,  Masaru Takahashi ,  Fuminobu Murakami ,  Shinichi Matsui ,  Masahiro Yamamoto

IPC: C21D9/46 ,  C21D6/00 ,  C21D8/00 ,  C21D8/12 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  H01F1/147 ,  H01F41/02

CPC classification number: C21D9/46 ,  C21D6/005 ,  C21D6/008 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1272 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  H01F1/14775 ,  H01F41/02 ,  C22C2202/02

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} orientation in a central area along a thickness direction of the silicon steel sheet is 12 to 35.

公开(公告)号：US11421297B2

公开(公告)日：2022-08-23

申请号：US16975334

申请日：2019-03-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Takeru Ichie ,  Masaru Takahashi ,  Fuminobu Murakami ,  Shinichi Matsui ,  Masahiro Yamamoto

IPC: C21D6/00 ,  C21D8/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  H01F1/147

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, ⅕t area, and ½t area from a surface of the silicon steel sheet along a thickness direction, the PDR is 50% or less.

公开(公告)号：US12168809B2

公开(公告)日：2024-12-17

申请号：US17797384

申请日：2021-02-19

Applicant: NIPPON STEEL CORPORATION

Inventor： Yoshihiro Arita ,  Takeru Ichie ,  Fuminobu Murakami

IPC: C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  C23G1/08

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 μm.

公开(公告)号：US11970750B2

公开(公告)日：2024-04-30

申请号：US18269435

申请日：2022-03-31

Applicant: NIPPON STEEL CORPORATION

Inventor： Nobusato Morishige ,  Takeru Ichie ,  Masato Yasuda ,  Masahide Urago ,  Fuminobu Murakami ,  Daichi Hamada ,  Atsushi Shibayama ,  Kazumi Mizukami ,  Daisuke Itabashi

IPC: C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06

CPC classification number: C21D8/1222 ,  C21D8/1233 ,  C21D8/1272 ,  C21D8/1277 ,  C21D9/46 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06

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 μm from the surface of the base material in the sheet thickness direction is 0.30 pieces/μm2 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 μm satisfies Formula (1):

(N2-5)/(N0-2)≤0.5  Formula (1).

公开(公告)号：US11124854B2

公开(公告)日：2021-09-21

申请号：US16487020

申请日：2018-03-07

Applicant: NIPPON STEEL CORPORATION

Inventor： Hiroshi Fujimura ,  Takeru Ichie ,  Yoshiaki Natori ,  Hiroyoshi Yashiki

IPC: C21D9/46 ,  C22C38/34 ,  C22C38/16 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/00 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  H01F1/147

Abstract: This non-oriented electrical steel sheet including, as a chemical composition, by mass %: C: 0.0100% or less; Si: more than 3.0% and 5.0% or less; Mn: 0.1 to 3.0%; P: 0.20% or less: S: 0.0018% or less: N: 0.0040% or less; Al: 0 to 0.9%; one or more selected from the group consisting of Sn and Sb: 0 to 0.100%; Cr 0 to 5.0%; Ni: 0 to 5.0%; Cu: 0 to 5.0%; Ca: 0 to 0.01%; rare earth elements (REM): 0 to 0.010%; and a remainder including Fe and impurities, in which an area ratio of a crystal structure A composed of crystal grains having a grain size of 100 μm or greater in a cross section parallel to a rolled surface of the non-oriented electrical steel sheet is 1 to 30%, an average grain size of a crystal structure B that is a crystal structure other than the crystal structure A is 25 μm or less, and a Vickers hardness HvA of the crystal structure A and a Vickers hardness HvB of the crystal structure B satisfy HvA/HvB≤1.000.