公开(公告)号：US20230002849A1

公开(公告)日：2023-01-05

申请号：US17901936

申请日：2022-09-02

Applicant: NIPPON STEEL CORPORATION

Inventor： Ryutaro YAMAGATA ,  Nobusato MORISHIGE ,  Ichiro TANAKA

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

Abstract: Grain-oriented electrical steel sheet excellent in magnetic properties and adhesion of a primary coating to a base steel sheet and with few defects where the base metal is exposed in point defects and a method for manufacturing grain-oriented electrical steel sheet are provided. This is characterized by being provided with a base steel sheet and a primary coating. The primary coating satisfies (1) Number density D3 of Al concentrated regions: 0.015 to 0.150/μm2 (2) (Area S5 of regions comprised of anchoring oxide layer regions and Al concentrated regions)/(area S3 of Al concentrated regions)≥0.30, (3) Distance H5 of mean value of heights in thickness direction of regions of comprised of anchoring oxide layer regions and Al concentrated regions minus HO: 0.4 to 4.0 μm, (4) (Perimeter L5 of regions comprised of anchoring oxide layer regions and Al concentrated regions)/(observed area S0): 0.020 to 0.500 μm/μ2, and (5) (Area S1 of anchoring oxide layer regions)/(observed area S0)≥0.15.

公开(公告)号：US20230243013A1

公开(公告)日：2023-08-03

申请号：US18009919

申请日：2021-06-23

Applicant: NIPPON STEEL CORPORATION

Inventor： Nobusato MORISHIGE ,  Kazumi MIZUKAMI ,  Ryutaro YAMAGATA ,  Takashi KATAOKA ,  Haruhiko ATSUMI ,  Daisuke ITABASHI ,  Junichi TAKAOBUSHI

IPC: C21D9/46 ,  C21D8/12 ,  C22C38/60 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  H01F1/147 ,  H01F41/00

CPC classification number: C21D9/46 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1272 ,  C21D8/1283 ,  C21D8/1255 ,  C22C38/60 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/002 ,  C22C38/001 ,  C21D8/1261 ,  H01F1/14775 ,  H01F41/00 ,  C21D2201/05 ,  C22C2202/02

Abstract: A new and improved method for producing grain-oriented electrical steel sheet enabling production of grain-oriented electrical steel sheet realizing high magnetic flux density and excellent in magnetic characteristics, that is, as one aspect, a method for producing grain-oriented electrical steel sheet comprising a hot rolling process, cold rolling process, primary recrystallization annealing process, finish annealing process, and flattening annealing process, wherein shot blasting treatment and/or leveling treatment and treatment for contact with a solution are performed, the solution contains Cu etc. in a predetermined amount, the pH is −1.5 or more and less than 7, a solution temperature is 15° C. or more and 100° C. or less, and the time during which the steel sheet is dipped in the solution is 5 seconds or more and 200 seconds or less.

公开(公告)号：US20220098688A1

公开(公告)日：2022-03-31

申请号：US17421562

申请日：2020-01-08

Applicant: NIPPON STEEL CORPORATION

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

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

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：US20220002831A1

公开(公告)日：2022-01-06

申请号：US17421309

申请日：2020-01-08

Applicant: NIPPON STEEL CORPORATION

Inventor： Nobusato MORISHIGE ,  Ryutaro YAMAGATA ,  Ichiro TANAKA ,  Takashi KATAOKA ,  Haruhiko ATSUMI ,  Yoshihiro SUWA ,  Kazumi MIZUKAMI

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

Abstract: Grain-oriented electrical steel sheet excellent in coating adhesion and magnetic properties is provided. The method for manufacturing grain-oriented electrical steel sheet excellent in coating adhesion and magnetic properties includes a process of heating to 1280° C. or more and hot rolling a slab containing, by mass %, Bi and a predetermined composition of constituents and having a balance of Fe and impurities so as to obtain hot rolled steel sheet, a process, after hot rolling annealing the hot rolled steel sheet, of cold rolling it one time or cold rolling it two times or more with process annealing performed interposed so as to obtain cold rolled steel sheet, a process of rapidly heating then decarburization annealing the steel sheet, a process of coating the surface of the cold rolled steel sheet after decarburization annealing with an annealing separator containing predetermined compounds including sulfates or sulfides and having MgO as its main constituent, then performing finish annealing, a process of performing strictly controlled finish annealing, and a process of coating an insulating coating, then performing flattening annealing.

公开(公告)号：US20230392225A1

公开(公告)日：2023-12-07

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 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/00 ,  C21D9/46

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

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：US20220081743A1

公开(公告)日：2022-03-17

申请号：US17421338

申请日：2020-01-08

Applicant: NIPPON STEEL CORPORATION

Inventor： Ryutaro YAMAGATA ,  Nobusato MORISHIGE ,  Ichiro TANAKA

IPC: C22C38/06 ,  H01F1/16 ,  C22C38/02 ,  C22C38/04 ,  C21D8/02 ,  C21D9/46

Abstract: Grain-oriented electrical steel sheet excellent in magnetic properties and adhesion of a primary coating to a base steel sheet and with few defects where the base metal is exposed in point defects and a method for manufacturing grain-oriented electrical steel sheet are provided. This is characterized by being provided with a base steel sheet and a primary coating. The primary coating satisfies (1) Number density D3 of Al concentrated regions: 0.015 to 0.150/μm2, (2) (Area S5 of regions comprised of anchoring oxide layer regions and Al concentrated regions)/(area S3 of Al concentrated regions)≥0.30, (3) Distance H5 of mean value of heights in thickness direction of regions of comprised of anchoring oxide layer regions and Al concentrated regions minus H0: 0.4 to 4.0 μm, (4) (Perimeter L5 of regions comprised of anchoring oxide layer regions and Al concentrated regions)/(observed area S0): 0.020 to 0.500 μm/μm2, and (5) (Area S1 of anchoring oxide layer regions)/(observed area S0)≥0.15.

公开(公告)号：US20220064753A1

公开(公告)日：2022-03-03

申请号：US17421215

申请日：2020-01-08

Applicant: NIPPON STEEL CORPORATION

Inventor： Ryutaro YAMAGATA ,  Nobusato MORISHIGE ,  Ichiro TANAKA

IPC: C21D9/46 ,  C22C38/60 ,  C22C38/16 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  C21D3/04 ,  H01F1/147

Abstract: Grain-oriented electrical steel sheet excellent in magnetic properties and excellent in adhesion of a primary coating to a base steel sheet, an annealing separator utilized for manufacture of grain-oriented electrical steel sheet, and a method for manufacturing grain-oriented electrical steel sheet are proposed. The grain-oriented electrical steel sheet is provided with a base metal steel sheet containing comprising a predetermined chemical composition and a primary coating formed on a surface of the base steel sheet and comprising Mg2SiO4 as a main constituent. The primary coating satisfies the conditions of (1) the number density D3 of the A1 concentrated region: 0.020 to 0.180/μm2 , (2) (total area S5 of regions which is anchoring oxide layer regions and is also A1 concentrated regions)/(total area S3 of Al concentrated regions)≥33%, (3) distance H5 of mean value of length in thickness direction of regions which is anchoring oxide layer regions and is also A1 concentrated regions minus H0: 0.4 to 4.0 μm, (4) (total area S1 of anchoring oxide layer regions)/(observed area S0)≥15%.

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.

公开(公告)号：US20230257841A1

公开(公告)日：2023-08-17

申请号：US18012830

申请日：2021-06-23

Applicant: NIPPON STEEL CORPORATION

Inventor： Nobusato MORISHIGE ,  Kazumi MIZUKAMI ,  Daisuke ITABASHI

IPC: C21D8/12 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/08 ,  C22C38/60 ,  C22C38/04 ,  C21D9/46

CPC classification number: C21D8/1283 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/06 ,  C22C38/08 ,  C22C38/60 ,  C22C38/04 ,  C21D8/1222 ,  C21D8/1272 ,  C21D9/46

Abstract: A new and improved method for producing electrical steel sheet enabling production of electrical steel sheet excellent in magnetic characteristics and coating film adhesion, the method for producing electrical steel sheet containing a process of bringing an electrical steel sheet containing, by mass %, C: more than 0% and 0.10% or less, Si: 2.5% or more and 4.5% or less, Mn: 0.01% or more and 5.0% or less, a total of one or more of S, Se, and Te: more than 0% and 0.050% or less, acid soluble Al: more than 0% and 5.0% or less, N: more than 0% and 0.015% or less, and P: more than 0% and 1.0% or less and having a balance of Fe and impurities into contact with a solution, the solution containing one or more elements from among Cu, Hg, Ag, Pb, Cd, Co, Zn, and Ni, a total of concentrations of the elements being 0.00001% or more and 1.0000% or less.

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.