公开(公告)号：US20220340991A1

公开(公告)日：2022-10-27

申请号：US17761055

申请日：2020-09-17

Applicant: NIPPON STEEL CORPORATION

Inventor： Masato YASUDA ,  Takeo ARAMAKI ,  Shinya YANO ,  Yoshihiro ARITA ,  Takashi KATAOKA ,  Kenichi MURAKAMI

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

Abstract: [Problem] To provide a grain-oriented electrical steel sheet which is further improved in terms of iron loss before magnetic domain control, while achieving a sufficient iron loss improvement effect even in the control of a heat-resistant magnetic domain where a sufficient iron loss improvement effect has not been achieved. [Solution] A grain-oriented electrical steel sheet according to one aspect of the present invention comprises abase steel sheet and a glass coating that is formed on the surface of the base steel sheet, and is characterized in that: the base steel sheet contains as chemical components, in mass %, 0.010% or less of C, from 2.00% to 4.00% of Si, from 0.05% to 1.00% of Mn, from 0.010% to 0.065% of Al, 0.004% or less of N and 0.010% or less of S, with the balance being made up of Fe and impurities; the oxygen concentration in the glass coating and the base steel sheet is 2,500 ppm or less; and if IAl_1 is the first peak intensity of Al and IAl_2 is the second peak intensity of Al in the concentration profile of Al, the relationship of mathematical formula (1) is satisfied. IAl_1

公开(公告)号：US20220243315A1

公开(公告)日：2022-08-04

申请号：US17428234

申请日：2020-02-07

Applicant: NIPPON STEEL CORPORATION

Inventor： Ichiro TANAKA ,  Takashi KATAOKA ,  Kazutoshi TAKEDA ,  Masamitsu KUBOTA ,  Hirotoshi TADA

IPC: C23C14/16 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D9/46 ,  C21D8/02 ,  C21D3/04

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

公开(公告)号：US20220090241A1

公开(公告)日：2022-03-24

申请号：US17422517

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Ichiro TANAKA ,  Takashi KATAOKA ,  Kazutoshi TAKEDA ,  Tomoya SUENAGA ,  Yuki KUNITA

IPC: C22C38/06 ,  C22C38/02 ,  C22C38/04 ,  C22C38/00 ,  C21D8/02 ,  C21D3/04 ,  C21D9/46 ,  H01F1/147

Abstract: A grain oriented electrical steel sheet includes a base steel sheet, an oxide layer, and a tension-insulation coating. When the iron oxide layer is analyzed by a fourier transform infrared spectroscopy, an absorbance A650 at 650 cm−1 and an absorbance A1250 at 1250 cm−1 satisfy 0.2≤A650/A1250≤5.0. Moreover, a magnetic flux density B8 in a rolling direction of the grain oriented electrical steel sheet is 1.90 T or more.

公开(公告)号：US20240177901A1

公开(公告)日：2024-05-30

申请号：US18283162

申请日：2022-03-28

Applicant: NIPPON STEEL CORPORATION

Inventor： Masataka IWAKI ,  Takashi KATAOKA ,  Tomohito TANAKA ,  Hideyuki HAMAMURA

IPC: H01F1/18 ,  C03C8/02 ,  C03C10/00 ,  C21D6/00 ,  C21D8/12 ,  C21D9/46 ,  C21D10/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/16 ,  C22C38/34 ,  C22C38/60 ,  C23D3/00 ,  C23D5/04 ,  C23D13/00

CPC classification number: H01F1/18 ,  C03C8/02 ,  C03C10/00 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1255 ,  C21D8/1261 ,  C21D8/1266 ,  C21D8/1283 ,  C21D8/1288 ,  C21D9/46 ,  C21D10/005 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/16 ,  C22C38/34 ,  C22C38/60 ,  C23D3/00 ,  C23D5/04 ,  C23D13/00 ,  C03C2204/00 ,  C03C2207/04 ,  C21D2201/05 ,  C22C2202/02

Abstract: This grain-oriented electrical steel sheet includes a base steel sheet, a glass coating formed on the base steel sheet, and a tension-applied insulation coating formed on the glass coating, in which, in the base steel sheet, a plurality of linear strain regions that extend continuously or intermittently in a direction intersecting with a rolling direction are present, the plurality of linear strain regions are each 210 μm or less in width in the rolling direction, the plurality of linear strain regions are parallel to each other, intervals of linear strain regions adjacent to each other in the rolling direction are 10 mm or less, and magnetostriction λ0-pb in a unit of μm/m when the grain-oriented electrical steel sheet is excited up to 1.7 T and magnetostriction λ0-pa in a unit of μm/m when the grain-oriented electrical steel sheet is heat-treated at 800° C. for 4 hours and then excited up to 1.7 T satisfy 0.02≤λ0-pb−λ0-pa≤0.20.

公开(公告)号：US20220341009A1

公开(公告)日：2022-10-27

申请号：US17761043

申请日：2020-09-17

Applicant: NIPPON STEEL CORPORATION

Inventor： Masato YASUDA ,  Yoshihiro ARITA ,  Takashi KATAOKA ,  Kenichi MURAKAMI ,  Takeo ARAMAKI ,  Shinya YANO

IPC: C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02

Abstract: The purpose of the present invention is to provide a method for manufacturing a grain-oriented electrical steel sheet, whereby it becomes possible to manufacture a grain-oriented electrical steel sheet having further improved iron loss properties stably. (Solution) According to one aspect of the present invention, a method for manufacturing a grain-oriented electrical steel sheet is provided, the method being characterized by comprising a re-heating step, a hot rolling step, a hot-rolled sheet annealing step, a cold rolling step, a decarburization annealing step and a final annealing step, wherein the decarburization annealing step includes a heating step of heating a cold-rolled sheet from an inlet side temperature T0° C. to a soaking temperature T2° C. and a soaking step of keeping the temperature of the cold-rolled sheet at the soaking temperature T2° C., and the heating rate HR1 from the time point when the temperature of the cold-rolled sheet is an inlet side temperature T0° C. to the time point when the temperature of the cold-rolled sheet reaches a attained temperature T1° C. is 40° C./sec or more and the heating rate HR2 from the time point when the temperature of the cold-rolled sheet is the desired temperature T1° C. to the time point when the temperature of the cold-rolled sheet reaches the soaking temperature T2° C. is more than 15° C./sec to 30° C./sec in the heating in the decarburization annealing step.

公开(公告)号：US20210272728A1

公开(公告)日：2021-09-02

申请号：US17259119

申请日：2018-07-13

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi KATAOKA ,  Yoshiyuki USHIGAMI ,  Shuichi NAKAMURA ,  Hiroyasu FUJII ,  Yoichi ZAIZEN

IPC: H01F1/147 ,  C21D9/46 ,  C21D8/12 ,  C21D6/00 ,  C22C38/34 ,  C22C38/20 ,  C22C38/32 ,  C22C38/04 ,  C22C38/00 ,  C22C38/06 ,  C23C8/14

Abstract: A grain oriented electrical steel sheet includes: by mass %, 0.010% or less of C; 2.50 to 4.00% of Si; 0.0010 to 0.0100% of acid soluble Al; 0.012% or less of N; 1.00% or less of Mn; 0.02% or less of S; and a balance consisting of Fe and impurities, and has a tension-insulation coating at steel sheet surface and a SiO2 intermediate oxide film layer with an average thickness of 1.0 nm to 1.0 μm at an interface between the tension-insulation coating and the steel sheet surface. In the grain oriented electrical steel, a time differential curve fM(t) of a glow discharge optical emission spectrum of a metallic element M (Al) in the SiO2 intermediate oxide film layer satisfies a predetermined condition.

公开(公告)号：US20210054489A1

公开(公告)日：2021-02-25

申请号：US16981585

申请日：2019-03-22

Applicant: NIPPON STEEL CORPORATION

Inventor： Ichiro TANAKA ,  Takashi KATAOKA ,  Noriyoshi KUBOTA ,  Kazutoshi TAKEDA

IPC: C22C38/60 ,  C22C38/20 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C21D9/46 ,  C21D8/02

Abstract: A grain-oriented electrical steel sheet includes: a base steel sheet including, as a chemical composition, by mass %, C: 0.010% or less, Si: 2.50% to 4.00%, Mn: 0.050% to 1.000%, S+Se: 0.005% or less in total, Sol. Al: 0.005% or less, N: 0.005% or less, Bi+Te+Pb: 0% to 0.0300% in total, Sb: 0% to 0.50%, Sn: 0% to 0.50%, Cr: 0% to 0.50%, Cu: 0% to 1.0%, and a remainder of Fe and impurities; and a tension-applying insulation coating provided on a surface of the base steel sheet, in which, on the surface of the base steel sheet, an arithmetic average roughness Ra along a rolling 90° direction that is a direction perpendicular to a rolling direction is 0.60 μm or less, and when a cross section of the base steel sheet is observed along the rolling 90° direction, recessed parts having a depth of 0.1 μm or more and 2.0 μm or less are present on the surface of the base steel sheet in 1.0/100 μm or more and 6.0/100 μm or less.

公开(公告)号：US20250118468A1

公开(公告)日：2025-04-10

申请号：US18832028

申请日：2023-03-31

Applicant: NIPPON STEEL CORPORATION

Inventor： Haruhiko ATSUMI ,  Ryutaro YAMAGATA ,  Takashi KATAOKA ,  Takaaki HIRAYAMA

IPC: H01F1/147 ,  C21D6/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/16 ,  C22C38/34 ,  C22C38/40 ,  C22C38/60

Abstract: This grain-oriented electrical steel sheet is characterized in that the base steel sheet has a chemical composition containing, in mass %, Si:2.5-4.5%, Mn:0.01-1.00%, N:≤0.01%, C:≤0.01%, sol.A1:0.01%, S:≤0.01%, Se:≤0.01%, P:0.00-0.05%, Sb:0.00-0.50%, Sn:0.00-0.30%, Cr:0.00-0.50%, Cu:0.00-0.50%, Ni:0.00-0.50%, and Bi:0.0000-0.0100%, with the remainder including Fe and impurities, the magnetic flux density B8 in the rolling direction of the sheet is ≥1.93 T, a deformed region extending over the entire width of the sheet is periodically formed at an interval L of 3-30 mm, in a direction intersecting the rolling direction, this region has a width W of 0.2-30.6 mm, a protrusion having a maximum height Dprotrusion of 1-5 m is formed on one surface of this region, and a recessed part having a maximum depth Drecess of 1-4 μm is formed on the opposite surface.

公开(公告)号：US20240158895A1

公开(公告)日：2024-05-16

申请号：US18284263

申请日：2022-04-06

Applicant: NIPPON STEEL CORPORATION

Inventor： Kazutoshi TAKEDA ,  Takashi KATAOKA ,  Shinsuke TAKATANI ,  Yuuki KOGAKURA ,  Yuki KUNITA

IPC: C22C38/02 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/04 ,  C23C22/07

CPC classification number: C22C38/02 ,  C21D6/008 ,  C21D8/0273 ,  C21D9/46 ,  C22C38/004 ,  C22C38/04 ,  C23C22/07

Abstract: This grain-oriented electrical steel sheet includes: a base steel sheet; and an insulating coating formed on a surface of the base steel sheet, in which the base steel sheet includes an iron-based oxide layer containing an iron-based oxide on an insulating coating side, the insulating coating includes an intermediate layer formed on a base steel sheet side and containing a crystalline metal phosphate, and a tension coating layer formed on a surface side of the insulating coating, an average thickness of the iron-based oxide layer is 0.10 to 1.50 μm, an average thickness of the intermediate layer is 0.3 to 10.0 μm, an average thickness of the insulating coating is 2.0 to 10.0 μm, the crystalline metal phosphate of the intermediate layer is one or two or more of zinc phosphate, manganese phosphate, iron phosphate, and zinc calcium phosphate, the tension coating layer contains a metal phosphate and silica, and an amount of the silica in the tension coating layer is 20 to 60 mass %.

公开(公告)号：US20240150874A1

公开(公告)日：2024-05-09

申请号：US18281903

申请日：2022-03-28

Applicant: NIPPON STEEL CORPORATION

Inventor： Tomohito TANAKA ,  Masataka IWAKI ,  Nobusato MORISHIGE ,  Takashi KATAOKA ,  Hideyuki HAMAMURA

IPC: C22C38/02 ,  B23K26/06 ,  B23K26/352 ,  B23K101/18 ,  B23K103/04 ,  C21D8/12 ,  C22C38/00 ,  C22C38/04

CPC classification number: C22C38/02 ,  B23K26/0626 ,  B23K26/352 ,  C21D8/1283 ,  C21D8/1288 ,  C22C38/004 ,  C22C38/04 ,  B23K2101/18 ,  B23K2103/04 ,  C21D2201/05

Abstract: This grain-oriented electrical steel sheet includes a base steel sheet, a glass coating formed on the base steel sheet, and a tension-applied insulation coating formed on the glass coating, in the base steel sheet, a plurality of linear strains that extend continuously or intermittently in a direction intersecting with a rolling direction are present, and intervals in the rolling direction of the plurality of linear strains adjacent to each other are 10 mm or less, in a region where the strains are present, a closure domain is present, a length d of the closure domain in a sheet thickness direction from a surface of the base steel sheet is 30 to 60 μm, a length w in the rolling direction is 200 μm or less, and a ratio mid of a depth m from the surface of the base steel sheet where a compressive strain in the rolling direction present in the closure domain exhibits a maximum value to the length d is in a range of more than 0.30 and less than 0.90.