Method of producing grain-oriented electrical steel sheet

Patent metadata

Field	Value
Publication number	US-2019112685-A1
Application number	US-201615774370-A
Country	US
Kind code	A1
Filing date	Nov 30, 2016
Priority date	Dec 4, 2015
Publication date	Apr 18, 2019
Grant date	—

Abstract

A grain-oriented electrical steel sheet has magnetic properties improved over conventional grain-oriented electrical steel sheets. A method of producing a grain-oriented electrical steel sheet comprises: heating a steel slab at 1300° C. or less, the steel slab having a chemical composition containing C, Si, Mn, acid-soluble Al, S and/or Se, Sn and/or Sb, N, and a balance being Fe and inevitable impurities; subjecting the steel slab 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 performed therebetween, to obtain a cold rolled steel sheet with a final sheet thickness; subjecting the cold rolled steel sheet to primary recrystallization annealing; applying an annealing separator to a surface of the cold rolled steel sheet after the primary recrystallization annealing; and then subjecting the cold rolled steel sheet to secondary recrystallization annealing.

First claim

1 .- 8 . (canceled)

9 . A method of producing a grain-oriented electrical steel sheet, the method comprising:
heating a steel slab at 1300° C. or less, the steel slab having a chemical composition containing, in mass %,
C in an amount of 0.002% or more and 0.080% or less,
Si in an amount of 2.00% or more and 8.00% or less,
Mn in an amount of 0.02% or more and 0.50% or less,
acid-soluble Al in an amount of 0.003% or more and less than 0.010%,
S and/or Se in an amount of 0.005% or more and 0.010% or less in total,
Sn and/or Sb in an amount of 0.005% or more and 1.000% or less in total,
N in an amount of less than 0.006%, and
a balance being Fe and inevitable impurities;
subjecting the steel slab 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 performed therebetween, to obtain a cold rolled steel sheet with a final sheet thickness; subjecting the cold rolled steel sheet to primary recrystallization annealing; applying an annealing separator to a surface of the cold rolled steel sheet after subjection to the primary recrystallization annealing; and then subjecting the cold rolled steel sheet to secondary recrystallization annealing.

10 . The method of producing a grain-oriented electrical steel sheet according to claim 9 ,
wherein in the chemical composition, the total amount of Sn and/or Sb is in a range of 0.020% or more and 0.300% or less in mass %.

11 . The method of producing a grain-oriented electrical steel sheet according to claim 9 ,
wherein the chemical composition further contains, in mass %, one or more selected from
Ni in an amount of 0.005% or more and 1.5% or less,
Cu in an amount of 0.005% or more and 1.5% or less,
Cr in an amount of 0.005% or more and 0.1% or less,
P in an amount of 0.005% or more and 0.5% or less,
Mo in an amount of 0.005% or more and 0.5% or less,
Ti in an amount of 0.0005% or more and 0.1% or less,
Nb in an amount of 0.0005% or more and 0.1% or less,
V in an amount of 0.0005% or more and 0.1% or less,
B in an amount of 0.0002% or more and 0.0025% or less,
Bi in an amount of 0.005% or more and 0.1% or less,
Te in an amount of 0.0005% or more and 0.01% or less, and
Ta in an amount of 0.0005% or more and 0.01% or less.

12 . The method of producing a grain-oriented electrical steel sheet according to claim 10 ,
wherein the chemical composition further contains, in mass %, one or more selected from
Ni in an amount of 0.005% or more and 1.5% or less,
Cu in an amount of 0.005% or more and 1.5% or less,
Cr in an amount of 0.005% or more and 0.1% or less,
P in an amount of 0.005% or more and 0.5% or less,
Mo in an amount of 0.005% or more and 0.5% or less,
Ti in an amount of 0.0005% or more and 0.1% or less,
Nb in an amount of 0.0005% or more and 0.1% or less,
V in an amount of 0.0005% or more and 0.1% or less,
B in an amount of 0.0002% or more and 0.0025% or less,
Bi in an amount of 0.005% or more and 0.1% or less,
Te in an amount of 0.0005% or more and 0.01% or less, and
Ta in an amount of 0.0005% or more and 0.01% or less.

13 . The method of producing a grain-oriented electrical steel sheet according to claim 9 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to nitriding treatment.

14 . The method of producing a grain-oriented electrical steel sheet according to claim 10 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to nitriding treatment.

15 . The method of producing a grain-oriented electrical steel sheet according to claim 11 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to nitriding treatment.

16 . The method of producing a grain-oriented electrical steel sheet according to claim 12 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to nitriding treatment.

17 . The method of producing a grain-oriented electrical steel sheet according to claim 9 ,
wherein one or more selected from sulfide, sulfate, selenide, and selenate are added to the annealing separator.

18 . The method of producing a grain-oriented electrical steel sheet according to claim 10 ,
wherein one or more selected from sulfide, sulfate, selenide, and selenate are added to the annealing separator.

19 . The method of producing a grain-oriented electrical steel sheet according to claim 11 ,
wherein one or more selected from sulfide, sulfate, selenide, and selenate are added to the annealing separator.

20 . The method of producing a grain-oriented electrical steel sheet according to claim 12 ,
wherein one or more selected from sulfide, sulfate, selenide, and selenate are added to the annealing separator.

21 . The method of producing a grain-oriented electrical steel sheet according to claim 9 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to magnetic domain refining treatment.

22 . The method of producing a grain-oriented electrical steel sheet according to claim 10 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to magnetic domain refining treatment.

23 . The method of producing a grain-oriented electrical steel sheet according to claim 11 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to magnetic domain refining treatment.

24 . The method of producing a grain-oriented electrical steel sheet according to claim 12 , further comprising
after the cold rolling, subjecting the cold rolled steel sheet to magnetic domain refining treatment.

25 . The method of producing a grain-oriented electrical steel sheet according to claim 23 ,
wherein in the magnetic domain refining treatment, the cold rolled steel sheet after subjection to the secondary recrystallization annealing is irradiated with an electron beam.

26 . The method of producing a grain-oriented electrical steel sheet according to claim 24 ,
wherein in the magnetic domain refining treatment, the cold rolled steel sheet after subjection to the secondary recrystallization annealing is irradiated with an electron beam.

27 . The method of producing a grain-oriented electrical steel sheet according to claim 23 ,
wherein in the magnetic domain refining treatment, the cold rolled steel sheet after subjection to the secondary recrystallization annealing is irradiated with a laser.

28 . The method of producing a grain-oriented electrical steel sheet according to claim 24 ,
wherein in the magnetic domain refining treatment, the cold rolled steel sheet after subjection to the secondary recrystallization annealing is irradiated with a laser.

Assignees

• Jfe Steel Corp

Inventors

• Takenaka Masanori
• Hayakawa Yasuyuki
• Imamura Takeshi
• EHASHI Yuiko

Classifications

• H01F1/16

  in the form of sheets (H01F1/147 takes precedence) · CPC title

• C22C38/60

  containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur · CPC title

• C21D8/12

  during manufacturing of articles with special electromagnetic properties · CPC title

• C21D6/008

  containing Si · CPC title

• C21D8/1272 Primary

  Final recrystallisation annealing · CPC title