Grain-oriented electrical steel sheet and magnetic domain refining method therefor

Patent metadata

Field	Value
Publication number	US-2023405708-A1
Application number	US-202318237238-A
Country	US
Kind code	A1
Filing date	Aug 23, 2023
Priority date	Dec 26, 2017
Publication date	Dec 21, 2023
Grant date	—

Abstract

A grain-oriented electrical steel sheet according to an embodiment of the present invention includes: a groove on a line formed on one surface of an electrical steel sheet in a direction crossing a rolling direction; and a thermal shock portion on a line formed on one surface of the electrical steel sheet in the direction crossing the rolling direction, wherein a distance between the groove and the thermal shock portion is 1 mm or less.

First claim

1 . A grain-oriented electrical steel sheet, comprising:
a groove on a line formed on one surface of an electrical steel sheet in a direction crossing a rolling direction; and a thermal shock portion on a line formed on the other surface of the electrical steel sheet in the direction crossing the rolling direction, wherein a distance between an imaginary line in which the groove is symmetrically projected onto the other surface with respect to a center of thickness of the steel sheet and the thermal shock portion is 1 mm or less.

2 . The grain-oriented electrical steel sheet of claim 1 , wherein
a depth of the groove is 1 to 10% of a thickness of the steel sheet.

3 . The grain-oriented electrical steel sheet of claim 1 , wherein
a plurality of grooves are formed, and a distance between the grooves is 1.5 to 10 mm.

4 . The grain-oriented electrical steel sheet of claim 3 , wherein
a plurality of the thermal shock portions are formed, and a distance between the thermal shock portions is 1 to 5 times the distance between the grooves.

5 . A magnetic domain refining method of a grain-oriented electrical steel sheet, comprising:
preparing a grain-oriented electrical steel sheet; forming a groove by irradiating a laser on one surface of the grain-oriented electrical steel sheet in a direction crossing a rolling direction; and forming a thermal shock portion by irradiating a laser on one surface of the grain-oriented electrical steel sheet in the direction crossing the rolling direction, wherein a distance between the groove and the thermal shock portion is 1 mm or less.

6 . A magnetic domain refining method of a grain-oriented electrical steel sheet, comprising:
preparing a grain-oriented electrical steel sheet; forming a groove by irradiating a laser on one surface of the grain-oriented electrical steel sheet in a direction crossing a rolling direction; and forming a thermal shock portion by irradiating a laser on the other surface of the grain-oriented electrical steel sheet in the direction crossing the rolling direction, wherein a distance between an imaginary line in which the groove is symmetrically projected onto the other surface with respect to a center of thickness of the steel sheet and the thermal shock portion is 1 mm or less.

7 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 5 , wherein
in the forming of the groove, energy density of the laser is 0.5 to 2 J/mm 2 , and in the forming of the thermal shock portion, energy density of the laser is 0.05 to 0.2 J/mm 2 .

8 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 6 , wherein
in the forming of the groove, energy density of the laser is 0.5 to 2 J/mm 2 , and in the forming of the thermal shock portion, energy density of the laser is 0.05 to 0.2 J/mm 2 .

9 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 5 , wherein
in the forming of the groove, a beam length of the laser is 300 to 5000 μm in a rolling vertical direction of the steel sheet, and a beam width of the laser is 10 to 200 μm in a rolling direction of the steel sheet.

10 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 6 , wherein
in the forming of the groove, a beam length of the laser is 300 to 5000 μm in a rolling vertical direction of the steel sheet, and a beam width of the laser is 10 to 200 μm in a rolling direction of the steel sheet.

11 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 9 , wherein
in the forming of the thermal shock portion, a beam length of the laser is 1500 to 10,000 μm in a rolling vertical direction of the steel sheet, and a beam width of the laser is 100 to 1000 μm in a rolling direction of the steel sheet.

12 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 10 , wherein
in the forming of the thermal shock portion, a beam length of the laser is 1500 to 10,000 μm in a rolling vertical direction of the steel sheet, and a beam width of the laser is 100 to 1000 μm in a rolling direction of the steel sheet.

13 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 5 , further comprising
forming an insulating coating layer on a surface of the steel sheet.

14 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 6 , further comprising
forming an insulating coating layer on a surface of the steel sheet.

15 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 13 , further comprising
after the forming of the groove, forming an insulating coating layer on a surface of the steel sheet.

16 . The magnetic domain refining method of the grain-oriented electrical steel sheet of claim 14 , further comprising
after the forming of the groove, forming an insulating coating layer on a surface of the steel sheet.

Assignees

• Posco Co Ltd

Inventors

• Park Se-Min
• Kim Jae Soo
• Min Ki-Young
• Hong Seong-Cheol
• Lee Won-Gul

Classifications

• B23K26/0006 Primary

  taking account of the properties of the material involved (B23K26/32, B23K26/40 take precedence) · CPC title

• B23K26/356

  by shock processing · CPC title

• B23K26/364

  for making a groove or trench, e.g. for scribing a break initiation groove · CPC title

• B23K2103/04

  Steel {or steel} alloys · CPC title

• C21D8/1277 Primary

  involving a particular surface treatment (C21D8/1294 takes precedence) · CPC title