公开(公告)号：US20220154304A1

公开(公告)日：2022-05-19

申请号：US17437703

申请日：2019-03-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Masaru TAKAHASHI ,  Takeru ICHIE ,  Tesshu MURAKAWA ,  Shinichi MATSUI ,  Fuminobu MURAKAMI

IPC: C21D9/46 ,  C22C38/16 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23G1/08 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  H01F1/147

Abstract: A non oriented electrical steel sheet consists of a silicon steel sheet and an insulation coating. The silicon steel sheet includes an internally oxidized layer containing SiO2 in a surface thereof, an average thickness of the internally oxidized layer is 0.10 to 5.0 μm, and a vickers hardness in the internally oxidized layer is 1.15 to 1.5 times as compared with a vickers hardness in a thickness central area.

公开(公告)号：US20200040423A1

公开(公告)日：2020-02-06

申请号：US16606107

申请日：2018-07-19

Applicant: NIPPON STEEL CORPORATION

Inventor： Yoshiaki NATORI ,  Kazutoshi TAKEDA ,  Hiroyoshi YASHIKI ,  Miho TOMITA ,  Hiroshi FUJIMURA ,  Takeaki WAKISAKA ,  Tesshu MURAKAWA ,  Takuya MATSUMOTO ,  Hiroki HORI ,  Yuuya GOHMOTO ,  O UYAMA

IPC: C21D9/46 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  H01F1/147

Abstract: A non-oriented electrical steel sheet includes, as a chemical composition, by mass %: C: 0.0015% to 0.0040%; Si: 3.5% to 4.5%; Al: 0.65% or less; Mn: 0.2% to 2.0%; Sn: 0% to 0.20%; Sb: 0% to 0.20%; P: 0.005% to 0.150%; S: 0.0001% to 0.0030%; Ti: 0.0030% or less; Nb: 0.0050% or less; Zr: 0.0030% or less; Mo: 0.030% or less; V: 0.0030% or less; N: 0.0010% to 0.0030%; O: 0.0010% to 0.0500%; Cu: less than 0.10%; Ni: less than 0.50%; and a remainder including Fe and impurities, in which a product sheet thickness is 0.10 mm to 0.30 mm, an average grain size is 10 μm to 40 μm, an iron loss W10/800 is 50 W/Kg or less, a tensile strength is 580 MPa to 700 MPa, and a yield ratio is 0.82 or more.

公开(公告)号：US20240158896A1

公开(公告)日：2024-05-16

申请号：US18279757

申请日：2022-03-18

Applicant: NIPPON STEEL CORPORATION

Inventor： Tesshu MURAKAWA ,  Satoshi KANO

IPC: C22C38/34 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/06 ,  C22C38/60

CPC classification number: C22C38/34 ,  C21D6/008 ,  C21D8/0273 ,  C21D9/46 ,  C22C38/004 ,  C22C38/008 ,  C22C38/06 ,  C22C38/60

Abstract: This non-oriented electrical steel sheet has a predetermined chemical composition, when EBSD observation is performed on a surface parallel to a steel sheet surface, in a case where a total area is indicated by Stot, an area of {100} orientated grains is indicated by S100, an area of orientated grains in which a Taylor factor M becomes more than 2.8 is indicated by Styl, a total area of orientated grains in which the Taylor factor M becomes 2.8 or less is indicated by Stra, an average KAM value of the {100} orientated grains is indicated by K100, and an average KAM value of the orientated grains in which the Taylor factor M becomes more than 2.8 is indicated by Ktyl, 0.20≤Styl/Stot≤0.85, 0.05≤S100/Stot≤0.80, S100/Stot≥0.5, and K100/Ktyl≤0.990 are satisfied.

公开(公告)号：US20240043970A1

公开(公告)日：2024-02-08

申请号：US18272727

申请日：2022-03-31

Applicant: NIPPON STEEL CORPORATION

Inventor： Minako FUKUCHI ,  Yoshiaki NATORI ,  Tesshu MURAKAWA

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

CPC classification number: C22C38/02 ,  C22C38/06 ,  C22C38/004

Abstract: A non-oriented electrical steel sheet of the present invention has a chemical composition capable of causing α-γ transformation, in which, in a case where an area ratio of grains having a crystal orientation of an {hkl} orientation (within a tolerance of 10°) when measured by EBSD is denoted as Ahkl-uvw, A411−011 is 15.0% or more, and the non-oriented electrical steel sheet has an average grain size of 10.0 μm to 40.0 μm.

公开(公告)号：US20220356549A1

公开(公告)日：2022-11-10

申请号：US17774370

申请日：2020-11-13

Applicant: NIPPON STEEL CORPORATION

Inventor： Tesshu MURAKAWA ,  Miho TOMITA ,  Hiroshi FUJIMURA ,  Satoshi KANO

IPC: C22C38/16 ,  C22C38/02 ,  C22C38/06 ,  C22C38/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/04 ,  C22C38/08 ,  C22C38/10

Abstract: What is provided is a non-oriented electrical steel sheet having a chemical composition in which, by mass %, C: 0.010% or less, Si: 1.50% to 4.00%, sol. Al: 0.0001% to 1.0%, S: 0.010% or less, N: 0.010% or less, one or a plurality of elements selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu and Au: 2.50% to 5.00% in total are contained and a remainder includes Fe and impurities, in which a sheet thickness is 0.50 mm or less, and, in an arbitrary cross section, when an area ratio of {100} crystal grains is indicated by Sac, an area ratio of {110} crystal grains is indicated by Sag, and an area ratio of the {100} crystal grains in a region of up to 20% from a side where a KAM value is high is indicated by Sbc, Sac>Sbc>Sag and 0.05>Sag are satisfied.

公开(公告)号：US20220349037A1

公开(公告)日：2022-11-03

申请号：US17638461

申请日：2020-11-13

Applicant: NIPPON STEEL CORPORATION

Inventor： Tesshu MURAKAWA ,  Miho TOMITA ,  Satoshi KANO

IPC: C22C38/60 ,  C22C38/00 ,  C22C38/16 ,  C22C38/06 ,  C22C38/02 ,  C22C38/04 ,  C22C38/10 ,  C21D8/02

Abstract: A method for manufacturing a non-oriented electrical steel sheet includes a step of obtaining a hot-rolled steel sheet by performing hot rolling on a steel material having a predetermined chemical composition, a step of performing first cold rolling on the hot-rolled steel sheet, and a step of performing first annealing after the first cold rolling. A final pass of finish rolling is performed in a temperature range equal to or higher than an Ar1 temperature, and cooling of which an average cooling rate is in a range of 50 to 500° C./sec is started in 0.1 sec from completion of rolling of the final pass of the finish rolling and is performed up to a temperature range higher than 250° C. and equal to or lower than 700° C.

公开(公告)号：US20220186330A1

公开(公告)日：2022-06-16

申请号：US17425901

申请日：2020-02-14

Applicant: NIPPON STEEL CORPORATION

Inventor： Tesshu MURAKAWA ,  Hiroshi FUJIMURA ,  Takeaki WAKISAKA ,  Takeshi KUBOTA

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

Abstract: The present disclosure has as its object the provision of non-oriented electrical steel sheet excellent in magnetic properties which is free from any drop in magnetic flux density even after stress relief annealing and a method for manufacturing the same.
Non-oriented electrical steel sheet having a chemical composition containing C: 0.0030 mass % or less, Si: 2.0 mass % or more and 4.0 mass % or less, Al: 0.010 mass % or more and 3.0 mass % or less, Mn: 0.10 mass % or more and 2.4% mass or less, P: 0.0050 mass % or more and 0.20 mass % or less, S: 0.0030 mass % or less, and one or more elements selected from the group comprising Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: total 0.00050 mass % or more and having a balance of Fe and unavoidable impurities, where, when designating a mass % of Si as [Si], a mass % of Al as [Al], and a mass % of Mn as [Mn], a parameter Q shown by the following formula (1) is 2.0 or more, a random intensity ratio of the {100} orientation is 2.4 or more, and an average grain size is 30 μm or less: Q=[Si]+2[Al]−[Mn]  (1)

公开(公告)号：US20250140456A1

公开(公告)日：2025-05-01

申请号：US19009597

申请日：2025-01-03

Applicant: NIPPON STEEL CORPORATION

Inventor： Ichiro TANAKA ,  Takeaki WAKISAKA ,  Tesshu MURAKAWA ,  Yoshiaki NATORI ,  Hiroshi FUJIMURA

IPC: H01F1/147 ,  B32B15/01 ,  C21D6/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/16 ,  C22C38/20 ,  C22C38/32 ,  C22C38/34 ,  C22C38/60

Abstract: There is provided a non-oriented electrical steel sheet having a predetermined chemical composition, in which an area fraction of a crystal structure A composed of crystal grains having a grain size of 100 μm or more is 1% to 30% in a cross section parallel to a rolled plane of the non-oriented electrical steel sheet, an average grain size of a crystal structure B which is a crystal structure other than the crystal structure A is 40 μm or less, and a Vickers hardness HvA of the crystal structure A and a Vickers hardness HvB of the crystal structure B satisfy Equation 1 ((HvA2+HvB2)/2−(HvA+HvB)2/4≤7.0).

公开(公告)号：US20240153683A1

公开(公告)日：2024-05-09

申请号：US18281193

申请日：2022-03-18

Applicant: NIPPON STEEL CORPORATION

Inventor： Tesshu MURAKAWA

IPC: H01F1/147 ,  C21D6/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/30 ,  C22C38/32 ,  C22C38/34 ,  C22C38/40 ,  C22C38/60

CPC classification number: H01F1/14791 ,  C21D6/002 ,  C21D6/004 ,  C21D6/005 ,  C21D6/007 ,  C21D6/008 ,  C21D8/1233 ,  C21D8/1266 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/004 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/30 ,  C22C38/32 ,  C22C38/34 ,  C22C38/40 ,  C22C38/60 ,  C22C2202/02

Abstract: This non-oriented electrical steel sheet has a predetermined chemical composition, when EBSD observation is performed on a surface parallel to a steel sheet surface, in a case where a total area is indicated by Stot, an area of {411} orientated grains is indicated by S411, an area of orientated grains in which a Taylor factor M becomes more than 2.8 is indicated by Styl, a total area of orientated grains in which the Taylor factor M becomes 2.8 or less is indicated by Stra, an average KAM value of the {411} orientated grains is indicated by K411, and an average KAM value of the orientated grains in which the Taylor factor M becomes more than 2.8 is indicated by Ktyl, 0.20≤Styl/Stot≤0.85, 0.05≤S411/Stot≤0.80, S411/Stra≥0.50, and K411/Ktyl≤0.990 are satisfied.

公开(公告)号：US20240141463A1

公开(公告)日：2024-05-02

申请号：US18279342

申请日：2022-03-18

Applicant: NIPPON STEEL CORPORATION

Inventor： Tesshu MURAKAWA ,  Minako FUKUCHI

IPC: C22C38/02 ,  C22C38/00 ,  C22C38/06 ,  C22C38/32

CPC classification number: C22C38/02 ,  C22C38/002 ,  C22C38/004 ,  C22C38/06 ,  C22C38/32

Abstract: This non-oriented electrical steel sheet has a predetermined chemical composition, one or more particles that are a precipitate of a sulfide or an oxysulfide of one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd or both the sulfide and the oxysulfide and have a diameter of more than 0.5 μm are present in a visual field of 10000 μm2, and, when EBSD observation is performed on a surface parallel to a steel sheet surface, in a case where a total area is indicated by Stot, an area of {100} orientated grains is indicated by S100, an area of orientated grains in which a Taylor factor M becomes more than 2.8 is indicated by Styl, a total area of orientated grains in which the Taylor factor M becomes 2.8 or less is indicated by Stra, an average KAM value of the {100} orientated grains is indicated by K100, and an average KAM value of the orientated grains in which the Taylor factor M becomes more than 2.8 is indicated by Ktyl, 0.20≤Styl/Stot≤0.85, 0.05≤S100/Stot≤0.80, S100/Stra≥0.50, and K100/Ktyl≤0.990 are satisfied.