Method for forming linear groove on cold rolled steel strip and method for manufacturing grain-oriented electrical steel sheet

Patent metadata

Field	Value
Publication number	US-2018119242-A1
Application number	US-201515529141-A
Country	US
Kind code	A1
Filing date	Dec 10, 2015
Priority date	Dec 11, 2014
Publication date	May 3, 2018
Grant date	—

Abstract

A resist coating for etching use which enables high speed and high accuracy patterning is provided by applying, to a cold rolled steel strip, a positive resist ink which solubilizes upon exposure to light; then drying the positive resist ink to form a resist coating; then scanning a laser beam converged in a point shape in the width direction of the cold rolled steel strip to form a photosensitive portion; and then removing the photosensitive portion of the resist film with a developing solution. Subsequently, by dissolving and removing by etching a portion of the steel strip below the removed portion of the resist coating, a fine and uniform linear groove can be formed in a surface of the steel strip.

First claim

1 . A method for forming linear grooves on a steel strip, the method comprising: applying, to a continuously-traveling cold rolled steel strip, a positive resist ink which solubilizes upon exposure to light; then drying the positive resist ink to form a resist coating; then scanning a laser beam converged in a point shape in the width direction of the cold rolled steel strip to form a linear photosensitive portion; then removing the photosensitive portion of the resist film with a developing solution; and then performing etching to dissolve and remove a portion of the steel strip below the removed portion of the resist coating, to thereby form a linear groove.

2 . The method for forming linear grooves on a cold rolled steel strip according to claim 1 , wherein a thickness of the resist coating is set to 15 μm or less.

3 . The method for forming linear grooves on a cold rolled steel strip according to claim 1 , wherein a thickness of the resist coating is set to less than 5 μm.

4 . The method for forming linear grooves on a cold rolled steel strip according to claim 1 , wherein a plurality of the linear grooves are formed at an angle of 30° or less with respect to the width direction of the cold rolled steel strip and at a pitch of 20 mm or less in the longitudinal direction of the cold rolled steel strip.

5 . The method for forming linear grooves on a cold rolled steel strip according to claim 1 , wherein two or more aligners, each being configured to irradiate the cold rolled steel strip with the laser beam, are arranged in the width direction of the steel strip.

6 . The method for forming linear grooves on a steel strip according to claim 1 , wherein the cold rolled strip is irradiated with the laser beam across a width of 1 μm or more and 500 μm or less.

7 . The method for forming linear grooves on a cold rolled steel strip according to claim 1 , wherein a groove depth of each linear groove is set to 5 μm or more.

8 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 1 .

9 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 2 .

10 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 3 .

11 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 4 .

12 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 5 .

13 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 6 .

14 . A method for manufacturing a grain-oriented electrical steel sheet, comprising:
heating a silicon steel slab; then hot rolling the steel slab to obtain a hot-rolled sheet; optionally subjecting the hot-rolled sheet to hot band annealing; then subjecting the hot-rolled sheet to cold rolling either once, or twice or more with intermediate annealing performed therebetween, to obtain a cold rolled steel strip; then subjecting the cold rolled steel strip to decarburization annealing; then applying an annealing separator to the cold rolled steel strip; and subsequently subjecting the cold rolled steel strip to final annealing, wherein a linear groove is formed in a surface of the cold rolled steel strip by applying the method as recited in claim 7 .

15 . The method for forming linear grooves on a cold rolled steel strip according to claim 2 , wherein a plurality of the linear grooves are formed at an angle of 30° or less with respect to the width direction of the cold rolled steel strip and at a pitch of 20 mm or less in the longitudinal dir

Assignees

• Jfe Steel Corp

Inventors

• Kobayashi Hirokazu

Classifications

• C21D8/1294 Primary

  involving a localised treatment · CPC title

• C25F3/14

  locally · CPC title

• G03F7/40

  Treatment after imagewise removal, e.g. baking · CPC title

• B23K26/364

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

• C21D8/1255

  with diffusion of elements, e.g. decarburising, nitriding · CPC title