公开(公告)号：US20190233926A1

公开(公告)日：2019-08-01

申请号：US16312222

申请日：2017-08-04

Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION

Inventor： Kohichi SANO ,  Makoto UNO ,  Ryoichi NISHIYAMA ,  Yuji YAMAGUCHI ,  Natsuko SUGIURA ,  Masahiro NAKATA

IPC: C22C38/38 ,  C22C38/02 ,  C22C38/06 ,  C22C38/00 ,  C22C38/26 ,  C22C38/28 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/08 ,  C22C38/04 ,  C23C2/06 ,  C23C2/40

CPC classification number: C22C38/38 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D9/46 ,  C21D2201/05 ,  C21D2211/002 ,  C21D2211/005 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/26 ,  C22C38/28 ,  C22C38/58 ,  C23C2/06 ,  C23C2/40

Abstract: A steel sheet has a specific chemical composition and has a structure represented by, by area ratio, ferrite: 5 to 95%, and bainite: 5 to 95%. When a region that is surrounded by a grain boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 μm or more is defined as a crystal grain, the proportion of crystal grains each having an intragranular misorientation of 5 to 14° to all crystal grains is 20 to 100% by area ratio. Hard crystal grains A in which precipitates or clusters with a maximum diameter of 8 nm or less are dispersed in the crystal grains with a number density of 1×1016 to 1×1019 pieces/cm3 and soft crystal grains B in which precipitates or clusters with a maximum diameter of 8 nm or less are dispersed in the crystal grains with a number density of 1×1015 pieces/cm3 or less are contained, and the volume % of the hard crystal grains A/(the volume % of the hard crystal grains A +the volume % of the soft crystal grains B) is 0.1 to 0.9.

公开(公告)号：US10020101B2

公开(公告)日：2018-07-10

申请号：US14367654

申请日：2012-12-21

Applicant: JFE STEEL CORPORATION

Inventor： Shigehiro Takajo ,  Seiji Okabe

IPC: H01F1/16 ,  C21D8/12 ,  C22C38/00 ,  C21D1/38 ,  C21D1/34

CPC classification number: H01F1/16 ,  C21D1/34 ,  C21D1/38 ,  C21D8/12 ,  C21D8/1244 ,  C21D8/1294 ,  C21D2201/05 ,  C22C38/00

Abstract: Disclosed is a grain-oriented electrical steel sheet exhibiting low hysteresis loss and low coercive force, in which an increase in hysteresis loss due to laser irradiation or electron beam irradiation, which has been a conventional concern, is effectively inhibited. The grain-oriented electrical steel sheet has closure domain regions (X) formed to divide the magnetic domains in a rolling direction, from one end to the other in the width direction of the steel sheet, provided that Expression (1) is satisfied: −(500t−80)×s+230≤w≤−(500t−80)×s+330   Expression (1), where t represents a sheet thickness (mm); w represents a smaller one of the widths (μm) of the regions measured on the front and rear surfaces of the steel sheet, respectively, by using a Bitter method; and s represents an average number of the regions present within one crystal grain.

公开(公告)号：US09997283B2

公开(公告)日：2018-06-12

申请号：US14963625

申请日：2015-12-09

Applicant: POSCO

Inventor： Kyu-Seok Han ,  Jae-Soo Lim ,  Byung-Deug Hong ,  Chan-Hee Han

IPC: C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/60 ,  C21D8/12 ,  H01F1/147 ,  H01F1/16 ,  H01F1/01 ,  C22C38/00 ,  C30B29/52

CPC classification number: H01F1/01 ,  C21D8/12 ,  C21D8/1244 ,  C21D8/1272 ,  C21D2201/05 ,  C21D2211/004 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/60 ,  C30B29/52

Abstract: Provided is a grain-oriented electric steel sheet having superior magnetic property and to a grain-oriented electric steel sheet including 2.0 to 4.5 weight % of Si, 0.001 to 0.10 weight % of C, 0.010 weight % or lower of Al, 0.08 weight % or lower of Mn, 0.005 weight % or lower of N, 0.002 to 0.050 weight % of S, the remainder being Fe and other unavoidable impurities. The steel sheet having been subjected to secondary recrystallization using at least any one of grain boundary-segregated elementary S and an FeS precipitate as a grain growth inhibitor.

公开(公告)号：US20180119242A1

公开(公告)日：2018-05-03

申请号：US15529141

申请日：2015-12-10

Applicant: JFE STEEL CORPORATION

Inventor： Hirokazu KOBAYASHI

IPC: C21D8/12 ,  C25F3/06 ,  C25F3/14 ,  H01F1/16 ,  G03F7/40 ,  B23K26/364

CPC classification number: C21D8/1294 ,  B23K26/082 ,  B23K26/0846 ,  B23K26/18 ,  B23K26/364 ,  B23K26/40 ,  B23K2101/16 ,  B23K2103/04 ,  C21D8/12 ,  C21D8/1255 ,  C21D10/00 ,  C21D2201/05 ,  C25F3/06 ,  C25F3/14 ,  G03F7/40 ,  H01F1/16

Abstract: A resist coating for etching use which enables high speed and high accuracy patterning is provided by applying, to a cold rolled steel strip, a positive resist ink which solubilizes upon exposure to light; then drying the positive resist ink to form a resist coating; then scanning a laser beam converged in a point shape in the width direction of the cold rolled steel strip to form a photosensitive portion; and then removing the photosensitive portion of the resist film with a developing solution. Subsequently, by dissolving and removing by etching a portion of the steel strip below the removed portion of the resist coating, a fine and uniform linear groove can be formed in a surface of the steel strip.

公开(公告)号：US09905361B2

公开(公告)日：2018-02-27

申请号：US14430463

申请日：2012-12-11

Applicant: BAOSHAN IRON & STEEL CO., LTD.

Inventor： Kanyi Shen ,  Guobao Li ,  Shuangjie Chu ,  Yezhong Sun ,  Huabing Zhang ,  Yongjie Yang ,  Zhuochao Hu ,  Bin Zhao ,  Qi Xu ,  Jie Huang ,  Peili Zhang

IPC: H01F41/02 ,  C21D8/12 ,  C22C38/04 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  H01F1/18 ,  C21D3/04 ,  C21D6/00 ,  C23C8/26 ,  H01F1/147 ,  H01F41/32

CPC classification number: H01F41/02 ,  C21D3/04 ,  C21D6/008 ,  C21D8/12 ,  C21D8/1205 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1261 ,  C21D8/1272 ,  C21D8/1277 ,  C21D8/1283 ,  C21D2201/05 ,  C22C38/001 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C8/26 ,  H01F1/14783 ,  H01F1/14791 ,  H01F1/18 ,  H01F41/32

Abstract: A manufacturing method of oriented silicon steel with magnetic induction B8 of not less than 1.88 T, comprising the following steps: 1) smelting and continuous casting to obtain a slab, wherein the content of N is controlled at 0.002-0.014 wt % in the smelting stage; 2) hot-rolling; 3) cold-rolling; 4) decarbonizing and annealing; 5) nitriding treatment, wherein infiltrated nitrogen content [N]D is controlled to satisfy the formula: 328−0.14a−0.85b−2.33c≦[N]D≦362−0.16a−0.94b−2.57c, wherein a is the content of Als in the smelting step, with the unit of ppm; b is the content of N element, with the unit of ppm; and c is primary grains size, with the unit of μm; 6) coating a steel's surfaces with a magnesium oxide layer and annealing; and 7) applying an insulating coating.

公开(公告)号：US20180043474A1

公开(公告)日：2018-02-15

申请号：US15549784

申请日：2016-04-19

Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION

Inventor： Hideyuki HAMAMURA ,  Tatsuhiko SAKAI ,  Fumiaki TAKAHASHI ,  Hisashi MOGI ,  Shunsuke OKUMURA ,  Hirofumi IMAI

IPC: B23K26/364 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  B23K26/00 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  C21D3/04 ,  B05D3/02 ,  B05D7/14 ,  C22C38/42 ,  C21D9/46

CPC classification number: B23K26/364 ,  B05D3/0254 ,  B05D7/14 ,  B23K26/359 ,  C21D3/04 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D7/00 ,  C21D8/005 ,  C21D8/12 ,  C21D8/1255 ,  C21D8/1261 ,  C21D8/1294 ,  C21D9/46 ,  C21D2201/05 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C2202/02 ,  C25F1/00 ,  H01F1/16

Abstract: Provided is a grain-oriented electrical steel sheet including a steel sheet having a steel sheet surface in which a groove, which extends in a direction intersecting a rolling direction and of which a groove depth direction matches a sheet thickness direction, is formed. When an average value of a groove depth in a sheet thickness direction at a central portion of the groove in a longitudinal groove direction is set as an average groove depth D, a straight line, which connects a first point at which a groove depth in the sheet thickness direction becomes 0.05×D and a second point at which the groove depth becomes 0.50×D, at an inclined portion of the groove is set as a groove end straight line, an angle made by the steel sheet surface and the groove end straight line is set as a first angle θ, and an average value of a groove-width-direction length, which is a length of a line segment connecting two points at which a groove depth in the sheet thickness direction in a contour of the groove on the groove-width-direction cross-section becomes 0.05×D, is set as an average groove width W, an aspect ratio A obtained by dividing the average groove depth D by the average groove width W, and the first angle θ satisfy the following Expression (1). θ

公开(公告)号：US20180037965A1

公开(公告)日：2018-02-08

申请号：US15552297

申请日：2016-02-12

Applicant: JFE STEEL CORPORATION

Inventor： Shigehiro TAKAJO ,  Takeshi OMURA ,  Seiji OKABE

IPC: C21D8/12 ,  H01F1/16 ,  H01F27/245

CPC classification number: C21D8/1294 ,  C21D8/12 ,  C21D8/1288 ,  C21D9/46 ,  C21D2201/05 ,  H01F1/16 ,  H01F27/245

Abstract: Disclosed are a grain-oriented electrical steel sheet having strain regions extending in a direction transverse to a rolling direction at periodic interval s (mm) in the rolling direction. Each strain region has a closure domain region whose width in the rolling direction varies periodically on a steel sheet surface. Each closure domain region satisfies: Wmax/Wmin=1.2 or more and less than 2.5, where Wmax and Wmin respectively denote a maximum width and a minimum width on the steel sheet surface as measured in the rolling direction; Wave being 80 μm or more, where Wave denotes an average width on the steel sheet surface as measured in the rolling direction; D being 32 μm or more, where D denotes a maximum depth as measured in the sheet thickness direction; and (Wave*D)/s being 0.0007 mm or more and 0.0016 mm or less.

公开(公告)号：US20180022927A1

公开(公告)日：2018-01-25

申请号：US15545760

申请日：2016-02-02

Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION

Inventor： Kazutoshi TAKEDA ,  Kenji KOSUGE ,  Tatsuya TAKASE ,  Koji MUNEDA

IPC: C09D1/00 ,  C22C38/04 ,  B05D1/06 ,  B05D7/14 ,  B05D3/02 ,  C22C38/06 ,  C22C38/02

CPC classification number: C09D1/00 ,  B05D1/06 ,  B05D3/0254 ,  B05D7/14 ,  C08L27/00 ,  C08L33/00 ,  C09D5/00 ,  C09D7/40 ,  C21D8/1283 ,  C21D2201/05 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C2202/02 ,  C23C22/34 ,  C23C22/36 ,  C23C2222/20 ,  H01F1/18

Abstract: An electrical steel sheet has an insulating coating on a steel sheet surface. The insulating coating includes one or more selected from an inorganic salt, an oxide, and an organic resin. The insulating coating includes the inorganic salt and/or the oxide in an amount of 50% or more by mass in total based on the total mass of the insulating coating. The insulating coating has a fluorine concentration ranging from 2 ppm to 130 ppm. The insulating coating is free of a chromium compound. The insulating coating of this electrical steel sheet has excellent coating compatibility.

公开(公告)号：US20170327922A1

公开(公告)日：2017-11-16

申请号：US15535582

申请日：2015-12-21

Applicant: POSCO

Inventor： Hak-Cheol LEE ,  Sung-Ho JANG

IPC: C21D9/46 ,  C21D6/00 ,  C22C38/12 ,  C22C38/08 ,  C22C38/04 ,  C21D8/02 ,  C22C38/00 ,  C22C38/14 ,  C22C38/16 ,  C22C38/02

CPC classification number: C21D9/46 ,  C21D6/001 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/021 ,  C21D8/0226 ,  C21D8/0247 ,  C21D8/0263 ,  C21D2201/05 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/009 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16

Abstract: Provided are high-strength steel having superior brittle crack arrestability and a production method therefor. The high-strength steel comprises 0.05-0.1 wt % of C, 0.9-1.5 wt % of Mn, 0.8-1.5 wt % of Ni, 0.005-0.1 wt % of Nb, 0.005-0.1 wt % of Ti, 0.1-0.6 wt % of Cu, 0.1-0.4 wt % of Si, at most 100 ppm of P, and at most 40 ppm of S with the remainder being Fe and other inevitable impurities, and has microstructures including one structure selected from the group consisting of a single-phase structure of ferrite, a single-phase structure of bainite, a complex-phase structure of ferrite and bainite, a complex-phase structure of ferrite and pearlite, and a complex-phase structure of ferrite, bainite, and pearlite. The high-strength steel has high yield strength and superior brittle crack arrestability.

公开(公告)号：US20170263357A1

公开(公告)日：2017-09-14

申请号：US15606074

申请日：2017-05-26

Applicant: JFE Steel Corporation

Inventor： Kunihiro Senda ,  Hirotaka Inoue ,  Seiji Okabe

IPC: H01F1/147 ,  C25F3/14 ,  C22C38/00 ,  C22C38/60 ,  H01F1/16 ,  C22C38/02 ,  C25F3/06 ,  C22C38/06 ,  C22C38/16 ,  C21D8/12 ,  C21D1/26 ,  C25F1/06 ,  B21B3/02 ,  C22C38/04

CPC classification number: H01F1/14775 ,  B21B3/02 ,  B21B2001/221 ,  C21D1/26 ,  C21D8/12 ,  C21D8/1233 ,  C21D8/1244 ,  C21D8/1283 ,  C21D2201/05 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/004 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/16 ,  C22C38/60 ,  C25F1/06 ,  C25F3/06 ,  C25F3/14 ,  H01F1/16 ,  Y10T428/24545

Abstract: A method of manufacturing a grain oriented electrical steel sheet includes subjecting a steel slab to a rolling process including cold rolling to obtain a steel sheet with a final sheet thickness, the steel slab containing by mass % C: 0.01% to 0.20%, Si: 2.0% to 5.0%, Mn: 0.03% to 0.20%, sol. Al: 0.010% to 0.05%, N: 0.0010% to 0.020%, at least one element selected from S and Se in a total of 0.005% to 0.040%, and the balance including Fe and incidental impurities; forming, by a chemical process, a linear groove extending in a direction forming an angle of 45° or less with a direction orthogonal to a rolling direction of the steel sheet; subjecting the steel sheet to decarburization annealing; applying an annealing separator thereon mainly composed of MgO; and subjecting the steel sheet to final annealing to manufacture a grain oriented electrical steel sheet.