Non-grain-oriented electrical steel strip or sheet, component manufactured from it and method for producing a non-grain-oriented electrical steel strip or sheet

Patent metadata

Field	Value
Publication number	US-9637805-B2
Application number	US-201214118720-A
Country	US
Kind code	B2
Filing date	Dec 18, 2012
Priority date	Jan 5, 2012
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A non-grain-oriented electrical steel strip or sheet consisting of a steel which contains, in addition to iron and unavoidable impurities, (in wt. %) Si: 1.0-4.5%, Al: up to 2.0%, Mn: up to 1.0%, C: up to 0.01%, N: up to 0.01%, S: up to 0.012%, Ti: 0.1-0.5% P: 0.1-0.3%, wherein 1.0≦% Ti/% P≦2.0 applies for the % Ti/% P ratio. The NGO sheet or strip can be manufactured by cold rolling a hot strip of a steel having the previously mentioned composition into a cold strip and subjecting this cold strip to a final annealing process. Different variants of this final annealing process may be used to accentuate the properties of the strip or sheet. The non-grain-oriented electrical steel strip or sheet and components manufactured from such a sheet or strip for electrotechnical applications are characterized by increased strength and good magnetic properties.

First claim

The invention claimed is:

1. A method for producing a non-grain-oriented electrical steel strip or sheet, in which the following production steps are carried out:
a) providing a hot strip which consists of a steel comprising, in addition to iron and unavoidable impurities, (in wt. %)
Si: 1.0-4.5%,
Al: up to 2.0%,
Mn: up to 1.0%,
C: up to 0.01%,
N: up to 0.01%,
S: up to 0.012%,
Ti: 0.1-0.5%,
P: 0.1-0.3%,
wherein 1.0≦% Ti/% P≦2.0
applies for the % Ti/% P ratio of the Ti content % Ti to the P content % P;
b) cold rolling the hot strip into a cold strip and
c) final annealing the cold strip,
wherein during final annealing the cold strip passes through a short-term annealing process performed in a single pass through a single continuous annealing furnace, comprising
1) firstly annealing the cold strip in a first annealing stage over an annealing period of 1-100 seconds at an annealing temperature of at least 900° C. and at most 1150° C., and then
2) annealing the cold strip in a second annealing stage over an annealing period of 30-120 seconds at an annealing temperature of 500-850° C.

2. The method according to claim 1 , wherein the cold strip is subjected to a long-term annealing process extending over an annealing period of 0.5-20 hours at an annealing temperature of 550-660° C. in a bell-type annealing furnace after the second annealing stage of the short-term annealing process.

Assignees

• Thyssenkrupp Steel Europe Ag

Inventors

• Dorner Dorothee
• Fischer Olaf
• Telger Karl

Classifications

• C22C38/001

  containing N · CPC title

• C22C38/14 Primary

  containing titanium or zirconium · CPC title

• C21D2201/05

  Grain orientation · CPC title

• H01F1/16

  in the form of sheets (H01F1/147 takes precedence) · CPC title

• C22C38/04

  containing manganese · CPC title