Coating agent for forming grain-oriented electrical steel sheet coating and method for manufacturing grain-oriented electrical steel sheet

Patent metadata

Field	Value
Publication number	US-12305288-B2
Application number	US-202017434983-A
Country	US
Kind code	B2
Filing date	Mar 25, 2020
Priority date	Mar 25, 2019
Publication date	May 20, 2025
Grant date	May 20, 2025

Abstract

A coating agent for forming a grain-oriented electrical steel sheet coating able to form an aluminum borate coating high in adhesion and large in tension and a method for manufacturing the grain-oriented electrical steel sheet are provided. The coating agent for forming a grain-oriented electrical steel sheet coating of the present invention comprises an aluminum source containing aluminum oxide and/or an aluminum oxide precursor compound, a boron source containing a borate of an alkali metal, and silicon oxide and/or a silicon oxide precursor in an amount, converted to silicon oxide, of 5 mass % or more and 10 mass % or less with respect to a total solids concentration of the aluminum source and boron source, the aluminum source and the boron source contained so that, by molar ratio, Al/B: 0.5 to 2.0, a solids concentration of a total of the aluminum source and the boron source being 20 mass % or more and 38 mass % or less, and pH being 2.0 or more and 6.0 or less.

First claim

The invention claimed is:

1. A coating agent for forming a grain-oriented electrical steel sheet coating, comprising:
an aluminum source containing aluminum oxide and/or an aluminum oxide precursor compound,
a boron source containing a borate of an alkali metal, and
silicon oxide and/or a silicon oxide precursor in an amount, converted to silicon oxide, of 5 mass % or more and 10 mass % or less with respect to a total mass of the aluminum source and boron source,
the aluminum source and the boron source contained so that the B contained in the boron source and the Al contained in the aluminum source become, converted to molar ratio, Al/B: 0.5 to 2.0,
a solids concentration of a total of the aluminum source and the boron source is 20 mass % or more and 38 mass % or less, and
pH is 2.0 or more and 6.0 or less.

2. The coating agent for forming the grain-oriented electrical steel sheet coating according to claim 1 , wherein the boron source contains boric acid.

3. The coating agent for forming the grain-oriented electrical steel sheet coating according to claim 1 , wherein the alkali metal contains at least one of sodium and potassium.

4. The coating agent for forming the grain-oriented electrical steel sheet coating according to claim 1 , further containing one or more types of inorganic acids selected from the group comprising nitric acid and hydrochloric acid and/or one or more types of organic acids selected from the group comprising acetic acid, citric acid, and oxalic acid.

5. A method for manufacturing grain-oriented electrical steel sheet having a process of forming an aluminum borate coating using a coating agent for forming the grain-oriented electrical steel sheet coating according to claim 1 .

6. The coating agent for forming the grain-oriented electrical steel sheet coating according to claim 2 , wherein the alkali metal contains at least one of sodium and potassium.

7. The coating agent for forming the grain-oriented electrical steel sheet coating according to claim 2 , further containing one or more types of inorganic acids selected from the group comprising nitric acid and hydrochloric acid and/or one or more types of organic acids selected from the group comprising acetic acid, citric acid, and oxalic acid.

8. The coating agent for forming the grain-oriented electrical steel sheet coating according to claim 3 , further containing one or more types of inorganic acids selected from the group comprising nitric acid and hydrochloric acid and/or one or more types of organic acids selected from the group comprising acetic acid, citric acid, and oxalic acid.

9. A method for manufacturing grain-oriented electrical steel sheet having a process of forming an aluminum borate coating using a coating agent for forming the grain-oriented electrical steel sheet coating according to claim 2 .

10. A method for manufacturing grain-oriented electrical steel sheet having a process of forming an aluminum borate coating using a coating agent for forming the grain-oriented electrical steel sheet coating according to claim 3 .

11. A method for manufacturing grain-oriented electrical steel sheet having a process of forming an aluminum borate coating using a coating agent for forming the grain-oriented electrical steel sheet coating according to claim 4 .

Assignees

• Nippon Steel Corp

Inventors

• Takahashi Fumiaki

Classifications

• C23C22/46

  containing oxalates · CPC title

• H01F1/147

  Alloys characterised by their composition {(treatment thereof for enhancing their electromagnetic properties C21D8/12)} · CPC title

• H01F1/18

  with insulating coating · CPC title

• C23C22/68

  using aqueous solutions with pH between 6 and 8 · CPC title

• C23C22/50 Primary

  Treatment of iron or alloys based thereon · CPC title