Grain-oriented electrical steel sheet, iron core of transformer, transformer, and method for reducing noise of transformer

Patent metadata

Field	Value
Publication number	US-2019333662-A1
Application number	US-201716474646-A
Country	US
Kind code	A1
Filing date	Nov 17, 2017
Priority date	Dec 28, 2016
Publication date	Oct 31, 2019
Grant date	—

Abstract

A grain-oriented electrical steel sheet having an insulating film disposed on a surface thereon. The insulating film having a chemical composition comprising Si, P, O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, Mn, and Co. The insulating film has a crystallinity in a range of 20% or more, and a minimum tension provided to the steel sheet by the insulating film at a temperature in a range of 100° C. to 200° C. is 10 MPa or more.

First claim

1 . A grain-oriented electrical steel sheet having an insulating film disposed on a surface thereon, the insulating film having a chemical composition comprising Si, P, O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, Mn, and Co,
wherein the insulating film has a crystallinity of 20% or more, and a minimum tension provided to the steel sheet by the insulating film at a temperature in a range of 100° C. to 200° C. is 10 MPa or more.

2 . The grain-oriented electrical steel sheet according to claim 1 , wherein the insulating film has a static friction coefficient in a range of 0.21 or more and 0.50 or less.

3 . The grain-oriented electrical steel sheet according to claim 1 , wherein the chemical composition excludes Cr.

4 . The grain-oriented electrical steel sheet according to claim 1 , wherein the insulating film has an average film thickness in a range of 4.5 μm or less.

5 . An iron core of a transformer, the iron core including the grain-oriented electrical steel sheet according to claim 1 .

6 . A transformer including the iron core according to claim 5 .

7 . A method for reducing noise of a transformer, the method comprising providing an iron core of the transformer, the iron core including the grain-oriented electrical steel sheet according to claim 1 .

8 . The grain-oriented electrical steel sheet according to claim 2 , wherein the chemical composition excludes Cr.

9 . The grain-oriented electrical steel sheet according to claim 3 , wherein the insulating film has an average film thickness in a range of 4.5 μm or less.

10 . An iron core of a transformer, the iron core including the grain-oriented electrical steel sheet according to claim 2 .

11 . An iron core of a transformer, the iron core including the grain-oriented electrical steel sheet according to claim 3 .

12 . An iron core of a transformer, the iron core including the grain-oriented electrical steel sheet according to claim 4 .

13 . An iron core of a transformer, the iron core including the grain-oriented electrical steel sheet according to claim 9 .

14 . A transformer including the iron core according to claim 10 .

15 . A transformer including the iron core according to claim 11 .

16 . A transformer including the iron core according to claim 12 .

17 . A transformer including the iron core according to claim 13 .

18 . A method for reducing noise of a transformer, the method comprising providing an iron core of the transformer, the iron core including the grain-oriented electrical steel sheet according to claim 2 .

19 . A method for reducing noise of a transformer, the method comprising providing an iron core of the transformer, the iron core including the grain-oriented electrical steel sheet according to claim 3 .

20 . A method for reducing noise of a transformer, the method comprising providing an iron core of the transformer, the iron core including the grain-oriented electrical steel sheet according to claim 4 .

Assignees

• Jfe Steel Corp

Inventors

• Terashima Takashi
• Watanabe Makoto
• Takamiya Toshito
• Okubo Tomoyuki

Classifications

• H01F1/18

  with insulating coating · CPC title

• H01F1/153

  Amorphous metallic alloys, e.g. glassy metals {(making ferrous amorphous alloys C22C33/003)} · CPC title

• C22C38/00

  Ferrous alloys, e.g. steel alloys (cast-iron alloys C22C37/00) · CPC title

• C23C22/00

  Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals · CPC title

• C23C22/74 Primary

  for obtaining burned-in conversion coatings · CPC title