公开(公告)号：US20220090267A1

公开(公告)日：2022-03-24

申请号：US17421762

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Shinji YAMAMOTO ,  Yoshiyuki USHIGAMI ,  Shinsuke TAKATANI ,  Shuichi NAKAMURA

IPC: C23C22/07 ,  C21D9/46 ,  C21D8/02 ,  C21D3/04

Abstract: A grain-oriented electrical steel sheet includes a base steel sheet which contains Si and Mn, an intermediate layer which is disposed on a surface of the base steel sheet and contains a silicon oxide as a main component, and an insulation coating which is disposed on a surface of the intermediate layer. A final-annealed film is not substantially present on a surface of the base steel sheet. In a surface layer region of grain-oriented electrical steel sheet, a Mn-depletion layer having a valley portion of a Mn content in which a Mn content is lower than an average Mn content of the base steel sheet in a region deeper than the surface layer region is provided, and a Mn-rich layer having a peak portion of a Mn content in which a Mn content is higher than that in the valley portion of the Mn content is provided in a region closer to a surface of the insulation coating than the Mn-depletion layer.

公开(公告)号：US20210355557A1

公开(公告)日：2021-11-18

申请号：US17263824

申请日：2019-07-31

Applicant: NIPPON STEEL CORPORATION

Inventor： Shuichi NAKAMURA ,  Yusuke KAWAMURA ,  Shota MORIMOTO

IPC: C21D9/46 ,  C21D8/12 ,  C22C38/02 ,  C22C38/12

Abstract: A grain oriented electrical steel sheet includes the texture aligned with Goss orientation. In the grain oriented electrical steel sheet, when (α1 β1 γ1) and (α2 β2 γ2) represent deviation angles of crystal orientations measured at two measurement points which are adjacent on the sheet surface and which have an interval of 1 mm, the boundary condition BA is defined as [(α2−α1)2+(β2−β1)2+(γ2−γ1)2]1/2≥0.5°, and the boundary condition BB is defined as [(α2−α2)2+(β2−β1)2+(γ2−γ1)2]1/2≥2.0°, the boundary which satisfies the boundary condition BA and which does not satisfy the boundary condition BB is included.

公开(公告)号：US20220372589A1

公开(公告)日：2022-11-24

申请号：US17263840

申请日：2019-07-31

Applicant: NIPPON STEEL CORPORATION

Inventor： Shuichi NAKAMURA ,  Yusuke KAWAMURA

IPC: C21D8/12 ,  C21D9/46 ,  C22C38/02 ,  C22C38/00 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50

Abstract: A grain oriented electrical steel sheet includes the texture aligned with Goss orientation. In the grain oriented electrical steel sheet, when (α1 β1 γ1) and (α2 β2 γ2) represent deviation angles of crystal orientations measured at two measurement points which are adjacent on the sheet surface and which have an interval of 1 mm, the boundary condition BA is defined as |γ2−γ1|≥0.5°, and the boundary condition BB is defined as [(α2−α1)2+(β2−β1)2+(γ2−γ1)2]1/2≥2.0°, the boundary which satisfies the boundary condition BA and which does not satisfy the boundary condition BB is included.

公开(公告)号：US20220119905A1

公开(公告)日：2022-04-21

申请号：US17421938

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Shinsuke TAKATANI ,  Yoshiyuki USHIGAMI ,  Shuichi NAKAMURA ,  Shohji NAGANO ,  Shunsuke OKUMURA

IPC: C21D9/46 ,  C21D8/12 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/60 ,  C23G1/02 ,  C23C28/04

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 an oxidation degree is controlled when atmosphere includes hydrogen or a dew point is controlled when atmosphere consists of inert gas, and an insulation coating forming process where a baking temperature and a heat treatment temperature are controlled.

公开(公告)号：US20210388459A1

公开(公告)日：2021-12-16

申请号：US17422618

申请日：2020-01-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Yoshiyuki USHIGAMI ,  Shuichi NAKAMURA ,  Hiroyasu FUJII

IPC: C21D9/46 ,  C22C38/34 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/24 ,  C22C38/22 ,  C22C38/20 ,  C22C38/06 ,  C22C38/04 ,  C22C38/00 ,  C21D8/12 ,  C21D8/00 ,  C21D6/00 ,  C21D3/04 ,  C23C8/26 ,  C23C8/02 ,  C23C8/80 ,  H01F1/147

Abstract: A method for manufacturing a grain-oriented electrical steel sheet includes: a silicon steel material production process of producing a silicon steel material; a hot rolling process of obtaining a hot rolled sheet by subjecting the silicon steel material to hot rolling; a cold rolling process of obtaining a steel sheet having a final sheet thickness by subjecting the hot rolled sheet to a single cold rolling process or to multiple cold rolling processes having intermediate annealing performed between cold rolling processes; a decarburization annealing process of subjecting the steel sheet to decarburization annealing using a decarburization annealing furnace including a heating area and a soaking area; and a final annealing process of applying an annealing separator having alumina as a main component to the steel sheet and subjecting the steel sheet to final annealing, wherein, in the decarburization annealing process, when X represents the Cr content of the silicon steel material in terms of mass %, an oxidation degree P1 of an atmosphere gas in the heating area satisfies the following Expression 1 and an oxidation degree P2 of an atmosphere gas in the soaking area satisfies the following Expression 2: 0.18X−0.008≤P1≤0.25X+0.15≤0.20  (Expression 1); and 0.01≤P2≤0.15  (Expression 2).