US 12,018,357 B2
Non-oriented electrical steel sheet and method of producing same
Yukino Miyamoto, Tokyo (JP); Yoshiaki Zaizen, Tokyo (JP); and Yoshihiko Oda, Tokyo (JP)
Assigned to JFE STEEL CORPORATION, Tokyo (JP)
Appl. No. 17/754,146
Filed by JFE STEEL CORPORATION, Tokyo (JP)
PCT Filed Sep. 17, 2020, PCT No. PCT/JP2020/035362
§ 371(c)(1), (2) Date Mar. 25, 2022,
PCT Pub. No. WO2021/065555, PCT Pub. Date Apr. 8, 2021.
Claims priority of application No. 2019-183100 (JP), filed on Oct. 3, 2019.
Prior Publication US 2022/0290287 A1, Sep. 15, 2022
Int. Cl. C23C 10/08 (2006.01); C21D 6/00 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/60 (2006.01); C23C 10/60 (2006.01); H01F 1/147 (2006.01)
CPC C23C 10/08 (2013.01) [C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 9/46 (2013.01); C22C 38/002 (2013.01); C22C 38/008 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/60 (2013.01); C23C 10/60 (2013.01); H01F 1/14775 (2013.01); C22C 2202/02 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A non-oriented electrical steel sheet having an inner layer defined as a region where a Si content is less than an average Si content in a total sheet thickness t, and surface layers defined as regions where a Si content is greater than or equal to the average Si content in the total sheet thickness t, the surface layers being provided on both sides of the inner layer, the non-oriented electrical steel sheet comprising a chemical composition containing:
Si; and,
C: 0.020 mass % or less,
Mn: 0.010 mass % to 2.0 mass %, and
S: 0.0100 mass % or less, as average contents in the total sheet thickness t, with the balance being Fe and inevitable impurities, wherein
each of the surface layers has an average Si content [Si]1 of 2.5 mass % to 7.0 mass %,
the inner layer has an average Si content [Si]0 of 2.1 mass % to 5.0 mass %,
each of the surface layers has an in-plane tensile stress of 5 MPa to 48.6 MPa,
the total sheet thickness t of the non-oriented electrical steel sheet has a sheet thickness t of is 0.01 mm to 0.35 mm,
the surface layers have a total thickness t1 with a ratio tilt of the total thickness t1 to the total sheet thickness t being 0.10 to 0.70,
the non-oriented electrical steel sheet has an average N content [N] in the total sheet thickness t of 40 ppm or less, and
an iron loss W10/400 in W/kg at a maximum magnetic flux density of 1.0 T and a frequency of 400 Hz and the total sheet thickness tin mm satisfy the following formula (1):
W10/400≤8+30t  (1).