US 12,404,562 B2
Oriented electrical steel sheet and method for manufacturing same
Oh-Yeoul Kwon, Pohang-si (KR); Woo-Sin Kim, Pohang-si (KR); and Jong-Tae Park, Pohang-si (KR)
Assigned to POSCO CO., LTD, Pohang-si (KR)
Appl. No. 17/297,917
Filed by POSCO, Pohang-si (KR)
PCT Filed Nov. 26, 2019, PCT No. PCT/KR2019/016379
§ 371(c)(1), (2) Date May 27, 2021,
PCT Pub. No. WO2020/111735, PCT Pub. Date Jun. 4, 2020.
Claims priority of application No. 10-2018-0153118 (KR), filed on Nov. 30, 2018.
Prior Publication US 2022/0042126 A1, Feb. 10, 2022
Int. Cl. C21D 9/46 (2006.01); C21D 8/02 (2006.01); C21D 8/12 (2006.01); C22C 38/00 (2006.01)
CPC C21D 8/1283 (2013.01) [C21D 8/0205 (2013.01); C21D 8/0236 (2013.01); C21D 8/1244 (2013.01); C21D 9/46 (2013.01); C22C 38/00 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A grain-oriented electrical steel sheet, comprising:
grooves including a bottom portion and a side portion and positioned on a surface of the electrical steel sheets;
a metal oxide layer positioned on the grooves and
an insulating layer positioned on the metal oxide layer,
wherein the grooves include normal grooves and defective grooves,
thicknesses of the metal oxide layer positioned on the bottom portion and the side portion in the normal grooves exceed 0.5 μm, and thicknesses of the metal oxide layer positioned on the bottom portion and the side portion in the defective grooves are 0.5 μm or less,
the insulating layer positioned on the normal grooves has a thickness of 0.5 μm or more and less than 1.5 μm,
the insulating layer positioned on the defective grooves has a thickness of 1.5 to 10 μm,
the bottom portion of the grooves is a depth portion of 0.7 or more of an entire depth of the grooves, and the side portion of the grooves is a depth portion of less than 0.7 of the entire depth of the grooves,
the thicknesses of the insulating layer positioned on the defective grooves are thicker than the thicknesses of the insulating layer positioned on the normal grooves,
the defective grooves are 10 to 80% of all the grooves of the steel sheet, and
the thickness of the insulating layer on the side portion is less than 20% of the entire depth and the thickness of the insulating layer on the bottom portion is 20 to 80% of the entire depth.