Non oriented electrical steel sheet

Patent metadata

Field	Value
Publication number	US-11952641-B2
Application number	US-201917437703-A
Country	US
Kind code	B2
Filing date	Mar 20, 2019
Priority date	Mar 20, 2019
Publication date	Apr 9, 2024
Grant date	Apr 9, 2024

Abstract

A non oriented electrical steel sheet consists of a silicon steel sheet and an insulation coating. The silicon steel sheet includes an internally oxidized layer containing SiO2 in a surface thereof, an average thickness of the internally oxidized layer is 0.10 to 5.0 μm, and a Vickers hardness in the internally oxidized layer is 1.15 to 1.5 times as compared with a Vickers hardness in a thickness central area.

First claim

What is claimed is:

1. A non oriented electrical steel sheet comprising a silicon steel sheet and an insulation coating, characterized in that
the silicon steel sheet consists of, as a chemical composition, by mass %,
more than 2.00 to 4.00% of Si,
0.10 to 3.00% of Al,
0.10 to 2.00% of Mn,
0.0030% or less of C,
0.050% or less of P,
0.005% or less of S,
0.005% or less of N,
0 to 0.40% of Sn,
0 to 1.00% of Cu,
0 to 0.40% of Sb,
0 to 0.0400% of REM,
0 to 0.0400% of Ca,
0 to 0.0400% of Mg, and
a balance consisting of Fe and impurities,
when viewing a cross section, whose cutting direction is parallel to a thickness direction, a central area is a thickness range of ⅝ to ⅜ of the silicon steel sheet, a Vickers hardness in the central area is 120 to 300 HV, and
when viewing the cross section, the silicon steel sheet includes an internally oxidized layer in a surface of the silicon steel sheet, wherein the internally oxidized layer contains SiO 2 , an average thickness of the internally oxidized layer is 0.10 to 5.0 μm, and a Vickers hardness in the internally oxidized layer is 1.15 to 1.5 times the Vickers hardness in the central area.

2. The non oriented electrical steel sheet according to claim 1 ,
wherein the silicon steel sheet contains, as the chemical composition, by mass %, at least one selected from a group of
0.02 to 0.40% of Sn,
0.10 to 1.00% of Cu, and
0.02 to 0.40% of Sb.

3. The non oriented electrical steel sheet according to claim 1 ,
wherein the silicon steel sheet contains, as the chemical composition, by mass %, at least one selected from a group of
0.0005 to 0.0400% of REM,
0.0005 to 0.0400% of Ca, and
0.0005 to 0.0400% of Mg.

4. The non oriented electrical steel sheet according to claim 1 ,
wherein the Vickers hardness in the internally oxidized layer is 155 to 450 HV.

5. The non oriented electrical steel sheet according to claim 1 ,
wherein the average thickness of the internally oxidized layer is 0.55 to 5.0 μm.

6. A non oriented electrical steel sheet comprising a silicon steel sheet and an insulation coating, characterized in that
the silicon steel sheet contains, as a chemical composition, by mass %,
more than 2.00 to 4.00% of Si,
0.10 to 3.00% of Al,
0.10 to 2.00% of Mn,
0.0030% or less of C,
0.050% or less of P,
0.005% or less of S,
0.005% or less of N,
0 to 0.40% of Sn,
0 to 1.00% of Cu,
0 to 0.40% of Sb,
0 to 0.0400% of REM,
0 to 0.0400% of Ca,
0 to 0.0400% of Mg, and
a balance comprising Fe and impurities,
when viewing a cross section, whose cutting direction is parallel to a thickness direction, a central area is a thickness range of ⅝ to ⅜ of the silicon steel sheet, a Vickers hardness in the central area is 120 to 300 HV, and
when viewing the cross section, the silicon steel sheet includes an internally oxidized layer in a surface of the silicon steel sheet, wherein the internally oxidized layer contains SiO 2 , an average thickness of the internally oxidized layer is 0.10 to 5.0 μm, and a Vickers hardness in the internally oxidized layer is 1.15 to 1.5 times the Vickers hardness in the central area.

Assignees

• Nippon Steel Corp

Inventors

• Takahashi Masaru
• Ichie Takeru
• Murakawa Tesshu
• Matsui Shinichi
• Murakami Fuminobu

Classifications

• C21D8/00

  Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment (hardening articles or materials formed by forging or rolling with no further heating beyond that required for the formation C21D1/02) · CPC title

• C21D9/46 Primary

  for sheet metals · CPC title

• C21D6/005

  containing Mn · CPC title

• C21D6/008

  containing Si · CPC title

• C21D8/005

  Chemistry & Metallurgy · mapped topic