Patent ID: 11952646
Assignee: NIPPON STEEL CORPORATION
Field: Materials, metallurgy (Chemistry)
Classification: CPC C  H  B  Y | IPC B  C

Claim 0:
1. A grain-oriented electrical steel sheet comprising:
a base steel sheet;
an intermediate layer which is disposed in contact with the base steel sheet and mainly includes silicon oxide; and
an insulation coating which is disposed in contact with the intermediate layer and mainly includes phosphate and colloidal silica,
wherein the base steel sheet contains, as a chemical compositions, by mass %:
C: 0.085% or less;
Si: 0.80 to 7.00%;
Mn: 0.05 to 1.00%;
acid-soluble Al: 0.010 to 0.065%;
N: 0.0040% or less;
S: 0.0100% or less;
B: 0.0005 to 0.0080%; and

a remainder of Fe and impurities,
BN having an average particle size of 50 to 300 nm is present on a surface layer of the intermediate layer,
when a total thickness of the base steel sheet and the intermediate layer is defined as d, a time until a sputtering depth reaches a position of d/100 from an outermost surface of the intermediate layer when an emission intensity of B is measured using glow discharge emission spectrometry (GDS) is defined as t(d/100), and a time until the sputtering depth reaches a position of d/10 from the outermost surface of the intermediate layer is defined as t(d/10),
an emission intensity IB_t(d/100) of B at t(d/100) and an emission intensity IB_t(d/10) of B at t(d/10) satisfy the following Equation (1), and
a ratio of a major axis to a minor axis of the BN particle is 1.5 or less,

IB_t(d/100)>IB_t(d/10)  Equation (1).