High silicon steel sheet having excellent productivity and magnetic properties and method for manufacturing same

Patent metadata

Field	Value
Publication number	US-10134513-B2
Application number	US-201214366741-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Dec 20, 2011
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

Provided is a method for manufacturing a high silicon steel sheet having excellent producibility and magnetic properties. The method includes: casting a molten metal as a strip having a thickness of 5 mm or less, the molten metal comprising, by weight %, C: 0.05% or less (excluding 0%), N: 0.05% or less (excluding 0%), Si: 4% to 7%, Al: 0.5% to 3%, Si+Al: 4.5% to 8%, and the balance of Fe and inevitable impurities; hot-rolling the cast strip at a temperature of 800° C. or higher; annealing the hot-rolled strip at a temperature within a range of 900° C. to 1200° C.; cooling the annealed strip; warm-rolling the quenched strip at a temperature within a range of 300° C. to 700° C.; and finally annealing the warm-rolled strip at a temperature within a range of 800° C. to 1200° C.

First claim

The invention claimed is:

1. A method for manufacturing a high silicon steel sheet, the method comprising:
casting a molten metal by a strip casting machine as a strip having a thickness of 1 mm to 5 mm, the molten metal comprising, by weight %, C: 0.05% or less (excluding 0%), N: 0.05% or less (excluding 0%), Si: 4% to 6.3%, Al: 0.3% to 3%, Si+Al: 4.5% to 8%, and the balance of Fe and inevitable impurities;
hot-rolling the cast strip by a hot rolling mill at a temperature of 800° C. or higher;
annealing the hot-rolled strip at a temperature within a range of 900° C. to 1200° C.;
cooling the annealed strip at a rate of 100° C./sec to 200° C./sec to a temperature range of room temperature to 100° C.;
warm-rolling the cooled strip at a temperature within a range of 300° C. to 700° C.; and
annealing the warm-rolled strip at a temperature within a range of 800° C. to 1200° C.

2. The method of claim 1 , wherein the casting of the molten metal is performed under at least one of a nitrogen atmosphere and an argon atmosphere.

3. The method of claim 1 , wherein the annealing of the hot-rolled strip is performed under a non-oxidizing atmosphere.

4. The method of claim 3 , wherein the non-oxidizing atmosphere is at least one of a nitrogen atmosphere, an argon atmosphere, and a hydrogen and nitrogen mixture atmosphere.

5. The method of claim 1 , where the warm-rolling of the cooled strip is performed until the cooled strip has a final thickness of 0.5 mm or less.

6. The method of claim 1 , wherein the thickness of the strip is 1 mm to 2 mm.

7. The method of claim 1 , wherein the annealing of the hot-rolled strip is performed for 10 seconds to 5 minutes.

8. The method of claim 1 , wherein the annealing of the warm-rolled strip is performed for 10 seconds to 5 minutes.

Assignees

• Posco

Inventors

• Hong Byung-Deug
• Koo Jin-Mo
• Lee Jae-Kon
• Park Sung-Jin
• Kim Sang-Hoon

Classifications

• C21D8/1261

  following hot rolling · CPC title

• C22C38/02

  containing silicon · CPC title

• C21D8/1211

  Rapid solidification; Thin strip casting · CPC title

• C21D8/1222 Primary

  Hot rolling · CPC title

• H01F1/14775 Primary

  in the form of sheets · CPC title