A coating for grain-oriented silicon steel coating layer, and grain-oriented silicon steel sheet and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-2025066922-A1
Application number	US-202318724975-A
Country	US
Kind code	A1
Filing date	Jan 13, 2023
Priority date	Jan 14, 2022
Publication date	Feb 27, 2025
Grant date	—

Abstract

The present disclosure relates to a coating, comprising a phosphate salt, a colloidal silica and a chromic acid compound, wherein the phosphate salt comprises magnesium dihydrogen phosphate and aluminum dihydrogen phosphate, and wherein a molar ratio of element Al to element Mg in the phosphate salt is 0.02 to 0.15. The present disclosure also relates to a grain-oriented silicon steel sheet, comprising: a substrate; and a coating layer on a surface of the substrate, wherein the coating layer is formed from the coating according to the present disclosure. The present disclosure further relates to a method for manufacturing a grain-oriented silicon steel sheet, comprising the steps of: applying the coating onto the surface of the substrate, and then performing a sintering treatment, wherein the substrate has a temperature, at which the sintering treatment is performed, of 800 to 880° C. The coating layer formed from the coating according to the present disclosure can impart higher tension and more excellent heat resistance to the grain-oriented silicon steel sheet, and has good promotion prospects and application effects.

First claim

1 . A coating, wherein the coating comprises: a phosphate salt, a colloidal silica and a chromic acid compound; and
wherein the phosphate salt comprises magnesium dihydrogen phosphate and aluminum dihydrogen phosphate, and a molar ratio of element Al to element Mg in the phosphate salt is 0.02 to 0.15, preferably 0.02 to 0.085.

2 . The coating according to claim 1 , wherein the coating has active ingredients consisting of: the phosphate salt, the colloidal silica and the chromic acid compound; and
wherein the phosphate salt comprises magnesium dihydrogen phosphate and aluminum dihydrogen phosphate, and the molar ratio of element Al to element Mg in the phosphate salt is 0.02 to 0.15, preferably 0.02 to 0.085.

3 . The coating according to claim 1 , wherein a mass ratio of the colloidal silica to the phosphate salt is 0.8 to 1.2.

4 . The coating according to claim 1 , wherein a mass ratio of the chromic acid compound to the phosphate salt is 0.1 to 0.5, and preferably, the mass ratio of the chromic acid compound to the phosphate salt is 0.2 to 0.4.

5 . A grain-oriented silicon steel sheet, comprising:
a substrate; and a coating layer on a surface of the substrate, wherein the coating layer is formed from the coating according to claim 1 .

6 . The grain-oriented silicon steel sheet according to claim 5 , wherein the grain-oriented silicon steel sheet has a surface tension of >8 MPa and a degree of tension deterioration before and after stress relief annealing treatment of ≤5%.

7 . The grain-oriented silicon steel sheet according to claim 5 , wherein the grain-oriented silicon steel sheet after stress relief annealing treatment has an iron loss P 17/50 of 0.6 to 1.37 W/kg.

8 . The grain-oriented silicon steel sheet according to claim 5 , wherein the coating layer has a single-sided dry film amount of 2 to 8 g/m 2 , preferably 3 to 6 g/m 2 .

9 . The grain-oriented silicon steel sheet according to claim 5 , wherein the substrate has a thickness of 0.15 to 0.50 mm.

10 . The grain-oriented silicon steel sheet according to claim 5 , wherein the substrate is a ferro-silicon alloy having a Goss texture, and preferably, the substrate has a content of element Si of 2% to 4% in percentage by mass.

11 . The grain-oriented silicon steel sheet according to claim 5 , wherein the substrate has a forsterite-free ceramic film or a forsterite-containing ceramic film on the surface thereof.

12 . A method for manufacturing the grain-oriented silicon steel sheet according to claim 5 , comprising the steps of: applying the coating onto the surface of the substrate, and then performing a sintering treatment, wherein the substrate has a temperature, at which the sintering treatment is performed, of 800 to 880° C.

13 . A grain-oriented silicon steel sheet, comprising:
a substrate; and a coating layer on a surface of the substrate, wherein the coating layer is formed from the coating according to claim 2 .

14 . The grain-oriented silicon steel sheet according to claim 13 , wherein the grain-oriented silicon steel sheet has a surface tension of >8 MPa and a degree of tension deterioration before and after stress relief annealing treatment of ≤5%.

15 . The grain-oriented silicon steel sheet according to claim 13 , wherein the grain-oriented silicon steel sheet after stress relief annealing treatment has an iron loss P 17/50 of 0.6 to 1.37 W/kg.

16 . The grain-oriented silicon steel sheet according to claim 13 , wherein the coating layer has a single-sided dry film amount of 2 to 8 g/m 2 , preferably 3 to 6 g/m 2 .

17 . The grain-oriented silicon steel sheet according to claim 13 , wherein the substrate has a thickness of 0.15 to 0.50 mm.

18 . The grain-oriented silicon steel sheet according to claim 13 , wherein the substrate is a ferro-silicon alloy having a Goss texture, and preferably, the substrate has a content of element Si of 2% to 4% in percentage by mass.

19 . The grain-oriented silicon steel sheet according to claim 13 , wherein the substrate has a forsterite-free ceramic film or a forsterite-containing ceramic film on the surface thereof.

20 . A method for manufacturing the grain-oriented silicon steel sheet according to claim 13 , comprising the steps of: applying the coating onto the surface of the substrate, and then performing a sintering treatment, wherein the substrate has a temperature, at which the sintering treatment is performed, of 800 to 880° C.

Assignees

• Baoshan Iron & Steel

Inventors

• Ji Yaming
• Ling Chen
• Li Guobao
• Yang Yongjie
• Wu Meihong
• Zhao Zipeng
• Ma Changsong

Classifications

• C23C22/33

  containing also phosphates · CPC title

• C23C22/82

  After-treatment · CPC title

• C23C22/74

  for obtaining burned-in conversion coatings · CPC title

• C22C38/02

  containing silicon · CPC title

• C21D8/1283

  Application of a separating or insulating coating · CPC title