公开(公告)号：US20240240293A1

公开(公告)日：2024-07-18

申请号：US18561841

申请日：2022-05-27

Applicant: JFE STEEL CORPORATION

Inventor： Takeshi IMAMURA ,  Ayaka YOSHIKAWA ,  Masanori TAKENAKA ,  Hiroi YAMAGUCHI

IPC: C22C38/02 ,  C21D1/26 ,  C21D3/04 ,  C21D6/00 ,  C21D8/00 ,  C21D8/12 ,  C22C38/04 ,  C23G1/08

CPC classification number: C22C38/02 ,  C21D1/26 ,  C21D3/04 ,  C21D6/008 ,  C21D8/005 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1255 ,  C21D8/1272 ,  C21D8/1283 ,  C22C38/04 ,  C23G1/08 ,  C21D2201/05

Abstract: To provide a method for producing a grain-oriented electrical steel sheet that can solve the problem of cracking in steel sheets during final cold rolling and that can stably produce a grain-oriented electrical steel sheet with low iron loss. A production method includes predetermined steps, wherein the conditions: T≤−4000×A+440, and T≤360 are satisfied, where A denotes an average C content in mass % in a predetermined region of the steel sheet after subjection to annealing preceding final cold rolling and before subjection to the final cold rolling, and T denotes a time in hours from just after the completion of the annealing preceding the final cold rolling to just before the start of the final cold rolling, and after the final cold rolling and before the decarburization annealing, pickling treatment is performed with a predetermined treatment solution.

公开(公告)号：US20240254601A1

公开(公告)日：2024-08-01

申请号：US18561064

申请日：2022-05-27

Applicant: JFE STEEL CORPORATION

Inventor： Takeshi IMAMURA ,  Ayaka YOSHIKAWA ,  Masanori TAKENAKA ,  Kazuaki TAMURA

IPC: C22C38/02 ,  C21D3/04 ,  C21D6/00 ,  C21D8/12 ,  C22C38/04 ,  C22C38/60 ,  C23G1/08

CPC classification number: C22C38/02 ,  C21D3/04 ,  C21D6/008 ,  C21D8/1222 ,  C21D8/1233 ,  C21D8/1261 ,  C21D8/1272 ,  C21D8/1283 ,  C22C38/04 ,  C22C38/60 ,  C23G1/08

Abstract: Disclosed is a method for producing a grain-oriented electrical steel sheet, including subjecting a steel material containing, by mass %, Si: 2.0-5.0%, Mn: 0.01-0.50%, and one or both of S and Se: 0.001-0.100% in total, to hot rolling, followed by cold rolling once, or twice or more with intermediate annealing in between, followed by decarburization annealing, followed by application and drying of an annealing separator mainly composed of MgO, followed by final annealing, followed by flattening annealing, in which the final annealing is performed in a predetermined atmosphere, the flattening annealing is accompanied by coating treatment including application of a coating solution, and prior to the application of the coating solution, pickling treatment is performed using an acid with a predetermined concentration at a temperature of 15° C. or higher for 1 second or more and 60 seconds or less.

公开(公告)号：US20250163551A1

公开(公告)日：2025-05-22

申请号：US18835348

申请日：2023-02-16

Applicant: JFE STEEL CORPORATION

Inventor： Takeshi IMAMURA ,  Ayaka YOSHIKAWA ,  Hiroi YAMAGUCHI

IPC: C22C38/02 ,  C21D6/00 ,  C21D8/12 ,  C21D9/46 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06 ,  C22C38/60

Abstract: We propose a method of producing a grain-oriented electrical steel sheet having improved magnetic flux density in material using an inhibitor. For a steel slab having a defined chemical composition, the temperature at the end of rough rolling by hot rolling and the time from the end of rough rolling to the start of finishing rolling satisfy a defined relationship, and time to reach 900° C. from 600° C. is 50 s or less.