Grain-oriented electrical steel sheet and method for producing grain-oriented electrical steel sheet

Patent metadata

Field	Value
Publication number	US-2025270667-A1
Application number	US-202318858046-A
Country	US
Kind code	A1
Filing date	Apr 21, 2023
Priority date	Apr 22, 2022
Publication date	Aug 28, 2025
Grant date	—

Abstract

A grain-oriented electrical steel sheet that can reduce iron loss and improve the adhesion of a secondary coating is provided. In a grain-oriented electrical steel sheet of the present embodiment, when a maximum emission intensity of Mg is defined as IMg/Mg, and an emission intensity of Sn at a sputtering time at which Mg exhibits the maximum emission intensity is defined as ISn/Mg, in glow emission spectroscopic spectra obtained by performing glow discharge optical emission spectroscopy in a thickness direction of a base steel sheet from a surface of a secondary coating, the glow emission spectroscopic spectra showing the relation of an emission intensity of Mg and an emission intensity of Sn with respect to a sputtering time, an intensity ratio Iref defined by Formula (1) is 0.0000 to 0.0006, and an iron loss W17/50 is less than 0.90 W/kg.Iref=ISn/Mg/IMg/Mg  (1)

First claim

1 - 7 . (canceled)

8 . A grain-oriented electrical steel sheet, comprising:
a base steel sheet, a primary coating formed on the base steel sheet, and a secondary coating formed on the primary coating, wherein: a chemical composition of the base steel sheet consists of, in mass %, Si: 2.50 to 4.50%, Mn: 0.01 to 1.00%, Sn: 0.05 to 0.30%, N: 0.010% or less, C: 0.010% or less, sol. Al: 0.010% or less, 0.020% or less in total of one or both of S and Se, P: 0.00 to 0.05%, Sb: 0.00 to 0.50%, Cr: 0.00 to 0.50%, Cu: 0.00 to 0.50%, Ni: 0.00 to 0.50%, and Bi: 0.0000 to 0.0100%, with the balance being Fe and impurities; and wherein: in glow emission spectroscopic spectra obtained by performing glow discharge optical emission spectroscopy from a surface of the secondary coating in a thickness direction of the base steel sheet, the glow emission spectroscopic spectra showing a relation of an emission intensity of Mg and an emission intensity of Sn with respect to a sputtering time: when a maximum emission intensity of Mg is defined as I Mg/Mg , and an emission intensity of Sn at the sputtering time at which Mg exhibits the maximum emission intensity is defined as I Sn/Mg , an intensity ratio I ref defined by Formula (1) is 0.0000 to 0.0006, and an iron loss W 17/50 measured in accordance with JIS C 2556:2015 is less than 0.90 W/kg,

I
ref

=

I

Sn
/
Mg

/

I

Mg
/
Mg

.

(
1
)

9 . The grain-oriented electrical steel sheet according to claim 8 , wherein:
the I Sn/Mg is 0.0021 or less.

10 . The grain-oriented electrical steel sheet according to claim 8 , wherein:
in the glow emission spectroscopic spectra, when the emission intensity of Sn at a time point at which a further 20.0 seconds passes from a sputtering time at which the I Sn/Mg is obtained is defined as I Sn/Mg+20 , an Sn concentration gradient ΔI Sn defined by Formula (2) is 0.0000 to 0.0004/sec,

Δ
⁢

I
Sn

=

(

I

Sn
/
Mg

+
20
-

⁢

I

Sn
/
Mg

)

/
20.

(
2
)

11 . The grain-oriented electrical steel sheet according to claim 9 , wherein:
in the glow emission spectroscopic spectra, when the emission intensity of Sn at a time point at which a further 20.0 seconds passes from a sputtering time at which the I Sn/Mg is obtained is defined as I Sn/Mg+20 , an Sn concentration gradient ΔI Sn defined by Formula (2) is 0.0000 to 0.0004/sec,

Δ
⁢

I
Sn

=

(

I

Sn
/
Mg

+
20
-

⁢

I

Sn
/
Mg

)

/
20.

(
2
)

12 . The grain-oriented electrical steel sheet according to claim 8 , wherein the chemical composition of the base steel sheet contains one or more of:
P: 0.01 to 0.05%, Sb: 0.01 to 0.50%, Cr: 0.01 to 0.50%, Cu: 0.01 to 0.50%, Ni: 0.01 to 0.50%, and Bi: 0.0001 to 0.0100%.

13 . The grain-oriented electrical steel sheet according to claim 9 , wherein the chemical composition of the base steel sheet contains one or more of:
P: 0.01 to 0.05%, Sb: 0.01 to 0.50%, Cr: 0.01 to 0.50%, Cu: 0.01 to 0.50%, Ni: 0.01 to 0.50%, and Bi: 0.0001 to 0.0100%.

14 . The grain-oriented electrical steel sheet according to claim 10 , wherein the chemical composition of the base steel sheet contains one or more of:
P: 0.01 to 0.05%, Sb: 0.01 to 0.50%, Cr: 0.01 to 0.50%, Cu: 0.01 to 0.50%, Ni: 0.01 to 0.50%, and Bi: 0.0001 to 0.0100%.

15 . The grain-oriented electrical steel sheet according to claim 11 , wherein the chemical composition of the base steel sheet contains one or more of:
P: 0.01 to 0.05%, Sb: 0.01 to 0.50%, Cr: 0.01 to 0.50%, Cu: 0.01 to 0.50%, Ni: 0.01 to 0.50%, and Bi: 0.0001 to 0.0100%.

16 . A method for producing a grain-oriented electrical steel sheet according to claim 8 , comprising
a hot rolling process of producing a hot-rolled steel sheet by performing hot rolling on a slab having a chemical composition consisting of:

Assignees

• Nippon Steel Corp

Inventors

• Atsumi Haruhiko
• Yamagata Ryutaro
• Kataoka Takashi
• KUNITA Yuki

Classifications

• H01F1/14791

  Fe-Si-Al based alloys, e.g. Sendust · CPC title

• H01F1/14783

  with insulating coating · CPC title

• C23G1/08

  Iron or steel · CPC title

• C21D8/1283

  Application of a separating or insulating coating · CPC title

• C21D8/1272

  Final recrystallisation annealing · CPC title