Patent ID: 11952641
Assignee: NIPPON STEEL CORPORATION
Field: Materials, metallurgy (Chemistry)
Classification: CPC C  H | IPC C  H

Claim 5:
6. A non oriented electrical steel sheet comprising a silicon steel sheet and an insulation coating, characterized in that
the silicon steel sheet contains, as a chemical composition, by mass %,
more than 2.00 to 4.00% of Si,
0.10 to 3.00% of Al,
0.10 to 2.00% of Mn,
0.0030% or less of C,
0.050% or less of P,
0.005% or less of S,
0.005% or less of N,
0 to 0.40% of Sn,
0 to 1.00% of Cu,
0 to 0.40% of Sb,
0 to 0.0400% of REM,
0 to 0.0400% of Ca,
0 to 0.0400% of Mg, and
a balance comprising Fe and impurities,
when viewing a cross section, whose cutting direction is parallel to a thickness direction, a central area is a thickness range of ⅝ to ⅜ of the silicon steel sheet, a Vickers hardness in the central area is 120 to 300 HV, and
when viewing the cross section, the silicon steel sheet includes an internally oxidized layer in a surface of the silicon steel sheet, wherein the internally oxidized layer contains SiO2, an average thickness of the internally oxidized layer is 0.10 to 5.0 μm, and a Vickers hardness in the internally oxidized layer is 1.15 to 1.5 times the Vickers hardness in the central area.