公开(公告)号：US20210040579A1

公开(公告)日：2021-02-11

申请号：US16976898

申请日：2019-02-06

Applicant: JFE STEEL CORPORATION

Inventor： Ken SAKAI ,  Shinichi KITAMURA ,  Kohei KURIHARA ,  Yusuke OTA

IPC: C21D9/56 ,  C21D1/26

Abstract: A method of annealing a steel sheet in an annealing furnace, including: supporting and conveying a steel sheet with hearth rolls; and supporting and conveying the steel sheet with a full-ceramic hearth roll as a hearth roll located in an area where a furnace temperature is equal to or higher than 950° C., wherein a main constituent of the full-ceramic hearth roll is silicon nitride with use of an Al—Y-based sintering aid.

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.