US 6,638,368 B2 · Non-oriented electrical steel sheet and method for producing the same

Abstract

The non-oriented electrical steel sheet having the following chemical composition: C: 0.01% or less, Si: 2.5% or less, Mn: 2% or less, Al: 1 to 5%, Si+Al+0.5×Mn: 2.5 to 5%, with a sheet thickness of 0.1 to 0.4 mm, an average grain diameter of 50 to 180 μm and a Vickers hardness of 130 to 210. The steel sheet is excellent in workability such as punchability and interlocking performance for forming it into cores for motors and also has a lower iron loss and higher magnetic flux density, and thus when used as a core in a motor, achieves the high a motor efficiency. The steel sheet is particularly suitable as a material for cores in inverter-controlled motors.

Claims7

Dependent claims

A method for producing a non-oriented electrical steel sheet having an average grain size of 50 to 180 microns and a Vickers hardness of 130 to 210 comprising the steps of:

(1) preparing a slab having the following chemical composition on a mass % basis,
C:
0.01% or less, Si:
2.5% or less, Mn:
2% or less, Al:
1 to 5%, Si+Al+0.5×Mn:
2.5 to 5%, Sb:
0.3% or less, Sn:
0.3% or less, B:
0.01% or less, the balance:
Fe and impurities;
(2) heating the slab at a temperature of 1300° C. or less and hot rolling the slab to a plate;
(3) after the hot rolling, cold rolling the plate to a sheet until its thickness becomes 0.1 to 0.4 mm;
and
(4) finish annealing the sheet at a temperature of 700 to 1150° C.

12 more elements

Dependencies are inferred from the claim text.

Facts

Application

09/985,444Filed 2 Nov 2001 · division

Priority

JP 11/16975916 Jun 1999

Published

US 2002/0043299 A118 Apr 2002

Granted

28 Oct 2003

Term ends

Not estimatedThe source records don’t support an estimate.

Classification16 codes

C22C 38/06
Ferrous alloys, e.g. steel alloys: containing aluminium
C22C 38/002
Ferrous alloys, e.g. steel alloys: containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
C22C 38/004
Ferrous alloys, e.g. steel alloys: very low carbon steels, i.e. having a carbon content of less than 0,01%
C22C 38/02
Ferrous alloys, e.g. steel alloys: containing silicon

Non-oriented electrical steel sheet and method for producing the same

Life of this patent

Non-oriented electrical steel sheet and method for producing the same

Life of this patent

Abstract

Claims7