Title:
METHOD FOR PRODUCING GRAIN-ORIENTED ELECTRICAL STEEL SHEET
Document Type and Number:
WIPO Patent Application WO/2020/149332
Kind Code:
A1
Abstract:
This method for producing a grain-oriented electrical steel sheet produces a grain-oriented electrical steel sheet which has an intermediate layer having silicon oxide as a principal component thereof on a base steel sheet surface where a foresteritic film is substantially absent, and also has an insulating film on the surface of the intermediate layer, the method having: a decarburization/annealing step for obtaining a decarburized/annealed steel sheet which has an oxygen content of 320ppm or less and a carbon content of 25ppm or less by subjecting a cold-rolled steel sheet containing Si to decarburization and annealing; a final annealing step for heating the decarburized/annealed steel sheet in a state where the surface thereof is coated with an annealing separation material and inducing the secondary recrystallization of the steel sheet; a removal step for obtaining a finished annealed steel sheet by removing the annealing separation material on the steel sheet following the final annealing step; an intermediate layer formation step for forming the intermediate layer by subjecting the finished annealed steel sheet to thermal oxidation annealing; and an insulating film formation step for forming the insulating film on the finished annealed steel sheet on which the intermediate layer has been formed.
Inventors:
IMAI TAKESHI (JP)
OKUMURA SHUNSUKE (JP)
OKUMURA SHUNSUKE (JP)
Application Number:
PCT/JP2020/001166
Publication Date:
July 23, 2020
Filing Date:
January 16, 2020
Export Citation:
Assignee:
NIPPON STEEL CORP (JP)
International Classes:
C21D8/12; C21D9/46; C22C38/00; C22C38/60; C23C22/00; H01F1/147
Foreign References:
| JPS60131976A | 1985-07-13 | |||
| JPH06185725A | 1994-07-08 | |||
| JPH0633142A | 1994-02-08 | |||
| JPS63260419A | 1988-10-27 | |||
| JP2018090862A | 2018-06-14 | |||
| JPH04337036A | 1992-11-25 | |||
| CN102021282A | 2011-04-20 | |||
| JP2019005399A | 2019-01-17 | |||
| JPH07118750A | 1995-05-09 | |||
| JPH07278668A | 1995-10-24 |
Other References:
N. MORITO ET AL., SCRIPTA METALLURGICA, vol. 10, 1976, pages 619 - 622
See also references of EP 3913085A4
See also references of EP 3913085A4
Attorney, Agent or Firm:
TANAI Sumio et al. (JP)
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