Title:
METHOD FOR MANUFACTURING NON-ORIENTED MAGNETIC STEEL SHEET
Document Type and Number:
WIPO Patent Application WO/2024/095666
Kind Code:
A1
Abstract:
A non-oriented magnetic steel sheet is manufactured by: hot-rolling a slab containing, by mass%, 0.005% or less of carbon, 3.0–5.0% of silicon, 3.0% or less of aluminum, 3.0% or less of manganese, and 0.01–0.5% of copper; annealing and cold-rolling a hot-rolled sheet thus obtained to obtain a cold-rolled sheet; and then applying finishing annealing. At this time, control is performed so that: the dew point DH of the furnace atmosphere when the steel sheet temperature in the heating zone is in the range from 500°C to 800°C is −20°C or below; the dew point DS of the furnace atmosphere when the steel sheet temperature in the heating zone is in the range from above 800°C up to the soaking temperature and in the soaking zone is −40°C or below; and the relationship between the dew point DH and the dew point DS satisfies the relationship DH > DS. Oxidation of the steel sheet surface after the finishing annealing is also suppressed. As a result, a low-iron-loss non-oriented magnetic steel sheet is stably obtained from a high-grade material that contains an abundance of silicon.
Inventors:
OKUBO TOMOYUKI (JP)
ZAIZEN YOSHIAKI (JP)
SAITO HAYATO (JP)
MARUYAMA SHIGEHIRO (JP)
ZAIZEN YOSHIAKI (JP)
SAITO HAYATO (JP)
MARUYAMA SHIGEHIRO (JP)
Application Number:
PCT/JP2023/036146
Publication Date:
May 10, 2024
Filing Date:
October 04, 2023
Export Citation:
Assignee:
JFE STEEL CORP (JP)
International Classes:
C21D8/12; C22C38/00; C22C38/16; C22C38/60; H01F1/147
Domestic Patent References:
| WO2020136993A1 | 2020-07-02 |
Foreign References:
| JP2018141206A | 2018-09-13 | |||
| JP2017128801A | 2017-07-27 | |||
| JP2018154853A | 2018-10-04 | |||
| JPH10183311A | 1998-07-14 | |||
| CN108570595A | 2018-09-25 |
Attorney, Agent or Firm:
GINZA MARONIE P.C. (JP)
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