公开(公告)号：US20230243010A1

公开(公告)日：2023-08-03

申请号：US18008927

申请日：2021-06-23

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi KATAOKA ,  Haruhiko ATSUMI ,  Ryutaro YAMAGATA ,  Nobusato MORISHIGE ,  Kazutoshi TAKEDA

IPC: C21D8/12 ,  C22C38/02 ,  C22C38/04 ,  C22C38/60 ,  C22C38/06 ,  C22C38/00 ,  C22C38/16 ,  C21D9/46 ,  C21D3/04

CPC classification number: C21D8/1283 ,  C22C38/02 ,  C22C38/04 ,  C22C38/60 ,  C22C38/06 ,  C22C38/001 ,  C22C38/16 ,  C21D9/46 ,  C21D3/04 ,  C21D8/1222 ,  C22C38/002 ,  C21D8/1272 ,  C21D2201/05

Abstract: Provided is a production method for a grain-oriented electrical steel sheet that is thin and has excellent magnetic characteristics. An embodiment of the present invention provides a production method that is for a grain-oriented electrical steel sheet and that comprises: a hot rolling step; an optional hot-rolled sheet-annealing step; an acid-washing step; a cold rolling step; a primary recrystallization-annealing step; a finishing-annealing step; and a planarization-annealing step. In the acid-washing step, an acid-washing solution containing 0.0001-5.00 g/L of Cu is used. The thickness of a cold-rolled steel sheet is 0.15-0.23 mm. The average temperature increase rate in the temperature range of 30-400° C. in a temperature increase process in the primary recrystallization step is more than 50° C./sec but not more than 1000° C./sec.

公开(公告)号：US20220119958A1

公开(公告)日：2022-04-21

申请号：US17422401

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Hiroyasu FUJII ,  Seiki TAKEBAYASHI ,  Yoshiyuki USHIGAMI ,  Takashi KATAOKA ,  Shunsuke OKUMURA

IPC: C23C22/78 ,  C21D9/46 ,  C21D3/04 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06

Abstract: This grain-oriented electrical steel sheet includes a steel sheet, an insulation coating disposed on the steel sheet, and a spinel present at a part on the steel sheet at an interface between the steel sheet and the insulation coating by being fitted into the insulation coating, in which an amount of the spinel is 5 to 50 mg/m2 per unit area of a surface of the steel sheet.

公开(公告)号：US20220098692A1

公开(公告)日：2022-03-31

申请号：US17421845

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

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

IPC: C21D9/46 ,  C21D8/12 ,  C22C38/00 ,  C22C38/60 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C22/18 ,  C23C22/20 ,  C23C22/74 ,  C23C28/04 ,  C23G1/08

Abstract: The grain-oriented electrical steel sheet is a grain-oriented electrical steel sheet which does not have an inorganic coating containing forsterite as a main component, including a base steel sheet having a predetermined chemical component, a silicon-containing oxide layer provided on the base steel sheet, an iron-based oxide layer provided on the silicon-containing oxide layer, and a tension-insulation coating provided on the iron-based oxide layer, having a thickness of 1 to 3 μm, and containing phosphate and colloidal silica as main components. When elemental analysis is performed from a surface of the tension-insulation coating in a sheet thickness direction by glow discharge optical emission spectrometry, predetermined requirements are satisfied.

公开(公告)号：US20220090242A1

公开(公告)日：2022-03-24

申请号：US17427535

申请日：2020-02-07

Applicant: NIPPON STEEL CORPORATION

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

IPC: C22C38/20 ,  C22C38/34 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06 ,  C21D9/46 ,  C21D8/02 ,  C21D3/04 ,  C23G1/08 ,  C22C38/60

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.

公开(公告)号：US20210017619A1

公开(公告)日：2021-01-21

申请号：US16981126

申请日：2019-03-19

Applicant: NIPPON STEEL CORPORATION

Inventor： Nobusato MORISHIGE ,  Takashi KATAOKA ,  Haruhiko ATSUMI ,  Yasuhiro MAYUMI ,  Toshiya TAKECHI ,  Naoto MASUMITSU ,  Tomoya SUENAGA ,  Masamitsu KUBOTA ,  Hideyuki HAMAMURA ,  Kazuhiko FUKUTANI

IPC: C21D9/46 ,  C21D8/12 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/20 ,  C22C38/60 ,  C23G1/00 ,  H01F1/147

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.

公开(公告)号：US20200381150A1

公开(公告)日：2020-12-03

申请号：US16971617

申请日：2019-02-26

Applicant: NIPPON STEEL CORPORATION

Inventor： Hideyuki HAMAMURA ,  Satoshi ARAI ,  Takashi KATAOKA ,  Shunsuke OKUMURA

IPC: H01F1/147 ,  C22C38/02 ,  C21D9/46 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  C21D3/04 ,  B23K26/364

Abstract: A grain-oriented electrical steel sheet according to the present embodiment is a grain-oriented electrical steel sheet having a groove formed on a surface, in which, in a cross section of the grain-oriented electrical steel sheet orthogonal to the groove, a KAM value is 0.1 or more and 3.0 or less in a region on a central side in a thickness direction of the grain-oriented electrical steel sheet with respect to the groove, the region being surrounded by a square having one side in contact with a groove bottom of the groove and having a length of 50 μm in each side.

公开(公告)号：US20240186039A1

公开(公告)日：2024-06-06

申请号：US18285481

申请日：2022-04-06

Applicant: NIPPON STEEL CORPORATION

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

IPC: H01F1/147 ,  C21D1/74 ,  C21D6/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C24/10 ,  C23C26/00 ,  C23C28/04

CPC classification number: H01F1/14783 ,  C21D1/74 ,  C21D6/005 ,  C21D6/008 ,  C21D8/1222 ,  C21D8/1255 ,  C21D8/1261 ,  C21D8/1272 ,  C21D8/1283 ,  C21D8/1288 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C24/10 ,  C23C26/00 ,  C23C28/04 ,  C21D2201/05 ,  C22C2202/02

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 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, the surface of the base steel sheet has an etch pit structure, an average thickness of the intermediate layer is 0.2 to 10.0 μm, an average thickness of the insulating coating is 2.0 to 10.0 μm, 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：US20230160034A1

公开(公告)日：2023-05-25

申请号：US18096276

申请日：2023-01-12

Applicant: NIPPON STEEL CORPORATION

Inventor： Ichiro TANAKA ,  Ryutaro YAMAGATA ,  Nobusato MORISHIGE ,  Takashi KATAOKA ,  Masaru TAKAHASHI

IPC: C21D9/46 ,  C21D3/04 ,  C21D6/00 ,  C21D8/00 ,  C21D8/12 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  H01F1/147

CPC classification number: C21D9/46 ,  C21D3/04 ,  C21D6/005 ,  C21D6/008 ,  C21D8/005 ,  C21D8/1233 ,  C21D8/1255 ,  C21D8/1272 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/008 ,  C22C38/16 ,  H01F1/147 ,  C22C2202/02

Abstract: Grain-oriented electrical steel sheet excellent in magnetic properties and excellent in adhesion of a primary coating to the steel sheet is provided. The grain-oriented electrical steel sheet is provided with a base steel sheet having a chemical composition containing C: 0.005% or less, Si: 2.5 to 4.5%, Mn: 0.050 to 1.000%, a total of S and Se: 0.005% or less, sol. Al: 0.005% or less, and N: 0.005% or less and having a balance of Fe and impurities and a primary coating having Mg2 SiO4 as a main constituent formed on a surface of the base steel sheet. A peak position of Al emission intensity obtained when conducting elemental analysis by glow discharge spectrometry from a surface of the primary coating in a thickness direction is present in a range of 2.0 to 12.0 µm from a surface of the primary coating to the thickness direction. A sum of perimeters of the Al oxides at the peak position of Al emission intensity is 0.20 to 1.00 µm/µm2, and a number density of Al oxides is 0.02 to 0.20 /µm2.

公开(公告)号：US20220344084A1

公开(公告)日：2022-10-27

申请号：US17761092

申请日：2020-09-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi KATAOKA ,  Ichiro TANAKA ,  Haruhiko ATSUMI ,  Kazutoshi TAKEDA ,  Ryutaro YAMAGATA ,  Nobusato MORISHIGE

IPC: H01F1/147 ,  C22C38/28 ,  C22C38/20 ,  C22C38/06 ,  C22C38/04 ,  C22C38/34 ,  C22C38/00 ,  C21D9/46 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  C21D3/04

Abstract: A grain oriented electrical steel sheet includes a base steel sheet, a glass film, and a tension-insulation coating. When a glow discharge emission spectroscopy is conducted from a surface of the glass film toward a depth direction, an analysis starting time Ts, a time TAlp at which Al shows a maximum emission intensity, an Al emission intensity F(TAlp) at the TAlp, a time TSip at which Si shows a maximum emission intensity, and an Al emission intensity F(TSip) at the TSip satisfy 0.05≤F(TSip)/F(TAlp)≤0.50 and 2.0≤(TAlp−Ts)/(TSip−Ts)≤5.0.

公开(公告)号：US20220090239A1

公开(公告)日：2022-03-24

申请号：US17421769

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

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

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

Abstract: A grain-oriented electrical steel sheet is a grain-oriented electrical steel sheet which does not have an inorganic coating containing forsterite as a main component and which includes: a base steel sheet containing a prescribed chemical component; a silicon-containing oxide layer provided on the base steel sheet; an iron-based oxide layer provided on the silicon-containing oxide layer; and a tension-insulation coating provided on the iron-based oxide layer, having a thickness of 1 to 3 μm, and containing phosphate and colloidal silica as main components. When the tension-insulation coating undergoes elemental analysis using a glow discharge optical emission spectrometry in a sheet thickness direction from a surface of the tension-insulation coating, a peak Si emission intensity satisfies a prescribed requirement.