公开(公告)号：US20240410029A1

公开(公告)日：2024-12-12

申请号：US18699366

申请日：2022-10-13

Applicant: JFE STEEL CORPORATION

Inventor： Hideto KAMBARA ,  Ken SAKAI ,  Shinichi KITAMURA ,  Toru NAKASHIMA

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

Abstract: An annealing facility in which a steel sheet after cold rolling is sequentially threaded through an annealing furnace having at least a first region, a second region, and a third region to continuously undergo finish annealing. Each of the regions of the annealing furnace is independently controllable in terms of the gas composition and the dew point of the atmosphere. The second region is composed of a heating zone, a soaking zone, and a cooling zone all having atmospheric temperatures of 900° C. or higher, with an atmospheric gas controlled to have a nitrogen content of 30 vol % or less and a dew point of −40° C. or lower. Further, an electrical steel sheet, preferably a non-oriented electrical steel sheet with low iron loss is produced by performing finish annealing using this annealing facility.

公开(公告)号：US20250146096A1

公开(公告)日：2025-05-08

申请号：US18838042

申请日：2023-03-02

Applicant: JFE STEEL CORPORATION

Inventor： Rieko IZUMI ,  Toshito TAKAMIYA ,  Akio FUJITA ,  Toru NAKASHIMA ,  Norihisa OKADA

IPC: C21D9/46 ,  C21D8/12

Abstract: Provided is a way to inhibit propagation of edge cracks. A method of producing a grain-oriented electrical steel sheet including, before final annealing, local strain with an indentation amount from the steel sheet surface of 5 μm to 30 μm is applied to a linear region that, when coiled and the coil is charged into a final annealing furnace, is separated from the axial end of the coil that comes into contact with a coil receiving base of the final annealing furnace by 5 mm or more and 20 mm or less in the axial direction of the coil and that extends continuously or discontinuously in a direction on that intersects the axial direction, in order to produce crystal grains having a misorientation angle of 15° or more from Goss orientation grains along 50% or more of the total length of the linear region.