Method of producing grain-oriented electrical steel sheet and annealing separator application line

Patent metadata

Field	Value
Publication number	US-12467106-B2
Application number	US-202017593560-A
Country	US
Kind code	B2
Filing date	Mar 26, 2020
Priority date	Mar 26, 2019
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

Provided is a method of producing a grain-oriented electrical steel sheet having uniform and good coating properties and magnetic properties throughout the length and/or width of the steel sheet. The method comprises: subjecting a steel slab to hot rolling, to cold rolling once or twice or more with intermediate annealing therebetween, and to primary recrystallization annealing; applying a liquid or slurry annealing separator to a resultant steel sheet; and thereafter coiling the steel sheet and subjecting the steel sheet to final annealing, wherein, before, after, or simultaneously with the application of the annealing separator, an additive for changing a composition of the annealing separator is adhered to the steel sheet at a weight ratio of 15% or less to a total of the annealing separator and the additive so as to vary the composition of the annealing separator in a longitudinal direction and/or width direction of the steel sheet.

First claim

The invention claimed is:

1 . A method of producing a grain-oriented electrical steel sheet, the method comprising:
subjecting a steel slab having a predetermined chemical composition to hot rolling, to obtain a hot-rolled steel sheet; subjecting the hot-rolled steel sheet to cold rolling once or twice or more with intermediate annealing therebetween, to obtain a cold-rolled steel sheet; subjecting the cold-rolled steel sheet to primary recrystallization annealing; applying a liquid or slurry annealing separator by a main line being a roll coater application device to the cold-rolled steel sheet after the primary recrystallization annealing; and thereafter coiling the steel sheet and subjecting the steel sheet to final annealing, wherein, before, after, or simultaneously with the application of the annealing separator, an additive aqueous solution for changing a composition of the annealing separator is adhered by an auxiliary line being a spray device to the cold-rolled steel sheet subjected to the primary recrystallization annealing at a weight ratio of 15% or less to a total of the liquid or slurry annealing separator and the additive aqueous solution so as to vary the composition of the annealing separator in at least one selected from a longitudinal direction and a width direction of the cold-rolled steel sheet.

Assignees

• Jfe Steel Corp

Inventors

• Yamaguchi Hiroi
• Terashima Takashi
• Watanabe Makoto

Classifications

• C21D8/00

  Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment (hardening articles or materials formed by forging or rolling with no further heating beyond that required for the formation C21D1/02) · CPC title

• H01F41/02

  for manufacturing cores, coils, or magnets (H01F41/14 takes precedence; for dynamo-electric machines H02K15/00) · CPC title

• H01F1/147

  Alloys characterised by their composition {(treatment thereof for enhancing their electromagnetic properties C21D8/12)} · CPC title

• C22C2202/02

  Magnetic · CPC title

• C22C38/12

  containing tungsten, tantalum, molybdenum, vanadium, or niobium · CPC title