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：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：US20210047704A1

公开(公告)日：2021-02-18

申请号：US16980461

申请日：2019-03-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Nobusato MORISHIGE ,  Takashi KATAOKA ,  Haruhiko ATSUMI ,  Yasuhiro MAYUMI ,  Atsushi SUZUKI ,  Tomoya SUENAGA ,  Teruyuki TAMAKI

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

Abstract: A method for manufacturing a grain-oriented electrical steel sheet including a step of hot-rolling a slab containing a predetermined component composition with a remainder including Fe and an impurity to obtain a hot-rolled steel sheet, a step of, after carrying out hot-rolled steel sheet annealing on the hot-rolled steel sheet, carrying out cold rolling to obtain a cold-rolled steel sheet, a step of carrying out primary recrystallization annealing including a rapid temperature increase at an average temperature increase velocity V of 400° C./s or more and imparting of a steel sheet tensile force S on the cold-rolled steel sheet, and a step of applying an annealing separating agent to a surface of the cold-rolled steel sheet after the primary recrystallization annealing and then carrying out flattening annealing.

公开(公告)号：US20200181725A1

公开(公告)日：2020-06-11

申请号：US16793670

申请日：2020-02-18

Applicant: NIPPON STEEL CORPORATION

Inventor： Hiroyoshi YASHIKI ,  Kenichi MURAKAMI ,  Nobusato MORISHIGE ,  Hirotoshi TADA ,  Yoshiaki NATORI

IPC: C21D8/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D9/46 ,  B22D11/00 ,  H01F1/16 ,  C22C38/60 ,  B32B15/04 ,  B32B15/18

Abstract: A grain-oriented electrical steel sheet includes a steel layer and an insulation coating arranged in directly contact with the steel layer thereon. The steel layer includes, as a chemical composition, by mass %, 2.9 to 4.0% of Si, 2.0 to 4.0% of Mn, 0 to 0.20% of Sn, and 0 to 0.20% of Sb. In the steel layer, a silicon content and a manganese content expressed in mass % satisfy 1.2%≤Si−0.5×Mn≤2.0%, and a tin content and an antimony content expressed in mass % satisfy 0.005%≤Sn+Sb≤0.20%.