公开(公告)号：US12123084B2

公开(公告)日：2024-10-22

申请号：US17421771

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Shinsuke Takatani ,  Yoshiyuki Ushigami

IPC: C22C38/54 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50

CPC classification number: C22C38/54 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0257 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C21D2201/05

Abstract: A method for producing a grain oriented electrical steel sheet includes a decarburization annealing process where an oxidation degree PH2O/PH2 is controlled and pickling is conducted after decreasing temperature, an annealing separator applying process where a mass ratio of MgO and Al2O3 in an annealing separator is controlled, a final annealing process where an oxidation degree is controlled when atmosphere includes hydrogen or a dew point is controlled when atmosphere consists of inert gas, an annealing separator removing process where water-washing is conducted using solution with inhibitor, and an insulation coating forming process where a mass ratio of phosphoric acid and metal compound in insulation coating forming solution is controlled.

公开(公告)号：US11946113B2

公开(公告)日：2024-04-02

申请号：US17421802

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Shinsuke Takatani ,  Yoshiyuki Ushigami

IPC: C21D9/46 ,  C21D8/02 ,  C21D8/12 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/60 ,  C23G1/08

CPC classification number: C21D9/46 ,  C21D8/0257 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1272 ,  C21D8/1283 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/60 ,  C23G1/08 ,  C21D2201/05

Abstract: A method for producing a grain oriented electrical steel sheet includes a decarburization annealing process where an oxidation degree PH2O/PH2 is controlled, an annealing separator applying process where a mass ratio of MgO and Al2O3 in an annealing separator is controlled, a final annealing process where hydrogen in mixed gas atmosphere is controlled to 50 volume % or more, an annealing separator removing process where water-washing is conducted using solution with inhibitor, a smoothing process where chemical-polished is conducted to control average roughness Ra, and an insulation coating forming process where insulation coating forming solution in which crystalline phosphide is included is applied.

公开(公告)号：US11923116B2

公开(公告)日：2024-03-05

申请号：US17298672

申请日：2019-11-21

Applicant: JFE STEEL CORPORATION

Inventor： Takeshi Omura ,  Yoshihisa Ichihara ,  Kunihiro Senda ,  Takahiro Koshihara

IPC: H01F1/147 ,  C21D1/34 ,  C21D6/00 ,  C21D9/46 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06 ,  C22C38/22 ,  C22C38/34 ,  C22C38/60

CPC classification number: H01F1/147 ,  C21D1/34 ,  C21D6/008 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/04 ,  C22C38/06 ,  C22C38/22 ,  C22C38/34 ,  C22C38/60 ,  C21D2201/05 ,  C22C2202/02

Abstract: Disclosed is a grain-oriented electrical steel sheet with extremely low iron loss by means of a magnetic domain refining technique. In a grain-oriented electrical steel sheet having a plurality of magnetic domains refined via a local strain introduction portion, when a direct-current external magnetic field is applied to the steel sheet in a rolling direction, for a magnetic flux leaked from the local strain introduction portion at a position 1.0 mm away from a surface of the steel sheet at a side of the local strain introduction portion, a value obtained by dividing an intensity level of a total leakage magnetic flux by an intensity level of a magnetic flux leaked due to causes other than strain is more than 1.2.

公开(公告)号：US11884988B2

公开(公告)日：2024-01-30

申请号：US17256891

申请日：2018-07-13

Applicant: NIPPON STEEL CORPORATION

Inventor： Shuichi Nakamura ,  Seiki Takebayashi ,  Yoshiyuki Ushigami ,  Shinsuke Takatani ,  Hiroyasu Fujii

IPC: C21D9/46 ,  C23C8/02 ,  C21D8/12 ,  C23C8/18 ,  C22C38/02 ,  C22C38/00

CPC classification number: C21D9/46 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1288 ,  C22C38/004 ,  C22C38/02 ,  C23C8/02 ,  C23C8/18 ,  C21D2201/05

Abstract: In a base sheet for a grain-oriented electrical steel sheet of the present invention, an amount of surface oxygen x per one surface of the base sheet and a value y of a peak (ΔR/R0 @1250 cm−1) of SiO2 on the surface of the base sheet obtained by infrared reflection spectroscopy satisfy y≥1500x2.5 and y≥0.24. A method of manufacturing the base sheet for a grain-oriented electrical steel sheet of the present invention includes: adjusting the amount of surface oxygen per one surface of a final-annealed grain-oriented silicon steel sheet to more than 0.01 g/m2 and 0.05 g/m2 or less, or more than 0.05 g/m2 and 0.10 g/m2 or less; and performing thermal oxidation annealing in an atmosphere in which an oxidation potential represented by a ratio PH2O/PH2 of water vapor pressure to hydrogen pressure is 0.0081 or less in a case where the amount of surface oxygen is more than 0.01 g/m2 and 0.05 g/m2 or less, or in an atmosphere in which the oxidation potential is 0.005 or less in a case where the amount of surface oxygen is more than 0.05 g/m2 and 0.10 g/m2 or less, at a soaking temperature of 1000° C. or lower to form an externally oxidized layer on a surface of the grain-oriented silicon steel sheet.

公开(公告)号：US11866812B2

公开(公告)日：2024-01-09

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

CPC classification number: C22C38/20 ,  C21D3/04 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/04 ,  C22C38/06 ,  C22C38/34 ,  C22C38/60 ,  C23G1/081 ,  C21D2201/05

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：US20230395300A1

公开(公告)日：2023-12-07

申请号：US18033131

申请日：2021-10-26

Applicant: NIPPON STEEL CORPORATION

Inventor： Yusuke KAWAMURA ,  Takahito MIZUMURA

IPC: H01F27/245 ,  H01F1/147 ,  C22C38/02 ,  C22C38/12 ,  C22C38/16 ,  C22C38/04 ,  C22C38/06 ,  C22C38/00 ,  C21D9/46 ,  C21D8/12 ,  C21D6/00 ,  C21D3/04 ,  C21D1/74

CPC classification number: H01F27/245 ,  H01F1/14775 ,  C22C38/02 ,  C22C38/12 ,  C22C38/16 ,  C22C38/04 ,  C22C38/06 ,  C22C38/004 ,  C22C38/002 ,  C22C38/001 ,  C21D9/46 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1255 ,  C21D8/1261 ,  C21D6/005 ,  C21D6/008 ,  C21D3/04 ,  C21D1/74 ,  C22C2202/02 ,  C21D2201/05

Abstract: This wound core is a wound core including a wound core main body obtained by laminating a plurality of polygonal annular grain-oriented electrical steel sheets in a side view, and the grain-oriented electrical steel sheet has planar portions and bent portions that are alternately continuous in a longitudinal direction, and in at least one bent portion, the crystal grain size Dpx of the grain-oriented electrical steel sheet is 2 W or less.

公开(公告)号：US20230392223A1

公开(公告)日：2023-12-07

申请号：US18031246

申请日：2021-07-26

Applicant: JFE STEEL CORPORATION

Inventor： Makoto WATANABE ,  Takashi TERASHIMA ,  Karin KOKUFU

IPC: C21D6/00 ,  C22C38/02 ,  C22C38/04 ,  C21D9/46

CPC classification number: C21D6/008 ,  C22C38/02 ,  C22C38/04 ,  C21D9/46 ,  C21D2201/05

Abstract: A grain oriented electrical steel sheet has excellent insulation property and includes: a steel sheet; and a coating disposed on each of both surfaces of the steel sheet, wherein an interlaminar current value after a rubbing test is not more than 0.10 A, the rubbing test being conducted by stacking two sheets of the grain oriented electrical steel sheet and rubbing the two sheets against each other to make 90 reciprocations under conditions of a surface pressure of 200 Pa, a rubbing speed of 0.10 m/s, and a reciprocating stroke of 50 mm.

公开(公告)号：US20230366101A1

公开(公告)日：2023-11-16

申请号：US18246183

申请日：2021-07-02

Applicant: JFE STEEL CORPORATION

Inventor： Shigehiro TAKAJO ,  Takeshi OMURA ,  Nobuko NAKAGAWA

IPC: C23F4/02 ,  C21D8/12

CPC classification number: C23F4/02 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1261 ,  C21D8/1272 ,  C21D2201/05

Abstract: A grain-oriented electrical steel sheet with extremely excellent magnetic properties by removing an etching resist coating well to form narrow grooves on a metal strip surface even with low-output laser, while reducing thermal effects on the metal strip caused by laser irradiation, and a method for forming grooves on a metal strip surface, having forming an etching resist coating with 0 to 70 lightness L* on at least one side of the metal strip, irradiating laser with less than 1.5 kW output on the etching resist coating while scanning the laser in a direction that intersects a rolling direction of the metal strip to remove a portion of the etching resist coating irradiated by the laser, and etching a portion of the metal strip below the removed portion of the etching resist coating to form grooves, the lightness L* being a L* value in a CIELAB color space (CIE1976L*a*b* color space).

公开(公告)号：US20230357875A1

公开(公告)日：2023-11-09

申请号：US18246334

申请日：2021-07-02

Applicant: JFE STEEL CORPORATION

Inventor： Shigehiro TAKAJO ,  Takeshi OMURA

IPC: C21D8/12 ,  C21D9/46 ,  C21D6/00 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00

CPC classification number: C21D8/1277 ,  C21D9/46 ,  C21D8/1261 ,  C21D8/1222 ,  C21D8/1233 ,  C21D6/008 ,  C21D6/005 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/002 ,  C22C38/001 ,  C21D2201/05 ,  C22C2202/02 ,  H01F1/14775

Abstract: A method for forming grooves on a surface of a metal strip, having applying a coating agent for etching resist coating formation to a roller; then, irradiating a laser on the roller while scanning the laser in an axial direction of the roller or in a direction inclined to the axial direction to remove a portion of the coating agent for etching resist coating formation irradiated by the laser; then, bringing the roller into contact with at least one side of the metal strip to transfer the coating agent for etching resist coating formation to the at least one side of the metal strip, with an unapplied area corresponding to the removed portion of the coating agent for etching resist coating formation.

公开(公告)号：US20230250506A1

公开(公告)日：2023-08-10

申请号：US18003339

申请日：2021-06-29

Applicant: JFE STEEL CORPORATION

Inventor： Yusuke SHIMOYAMA ,  Yukihiro SHINGAKI ,  Takashi TERASHIMA

IPC: C21D9/46 ,  C21D3/04 ,  C21D8/12 ,  C21D1/42 ,  C21D6/00 ,  C22C38/60 ,  C22C38/32 ,  C22C38/22 ,  C22C38/20 ,  C22C38/34 ,  C22C38/16 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00

CPC classification number: C21D9/46 ,  C21D3/04 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1261 ,  C21D8/1266 ,  C21D8/1272 ,  C21D1/42 ,  C21D8/1283 ,  C21D6/005 ,  C21D6/008 ,  C21D6/001 ,  C21D6/002 ,  C22C38/60 ,  C22C38/32 ,  C22C38/22 ,  C22C38/20 ,  C22C38/34 ,  C22C38/16 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/008 ,  C22C38/002 ,  C22C38/001 ,  C21D2201/05 ,  C22C2202/02

Abstract: Provided is a method of manufacturing a grain-oriented electrical steel sheet with which a grain-oriented electrical steel sheet with excellent magnetic properties and little variation in iron loss in the longitudinal direction of a coil can be stably manufactured. The method includes subjecting a steel slab to hot-rolling and optionally to annealing, then performing cold rolling once or twice or more to obtain a cold-rolled sheet with a final sheet thickness, and then subjecting the cold-rolled sheet to decarburization annealing and then secondary recrystallization annealing, where immediately before final cold rolling, a steel sheet is heated at a heating rate of 100° C./s or more to a heating temperature of 100° C. or higher and 350° C. or lower, and a time from when the steel sheet reaches the heating temperature to when it is bitten in a first pass of final cold rolling is set to within 5 seconds.