	US 11,788,168 B2
	Electrical steel strip that can be but doesn't have to be reannealed
Sebastian Sieron, Essen (DE); Philipp Szary, Witten (DE); Olaf Fischer, Bochum (DE); Abdullah Kahveci, Bochum (DE); and Karl Telger, Coesfeld (DE)
Assigned to ThyssenKrupp Steel Europe AG, Duisburg (DE)
Appl. No. 16/963,728
Filed by ThyssenKrupp Steel Europe AG, Duisburg (DE); and thyssenkrupp AG, Essen (DE)
PCT Filed Jan. 23, 2019, PCT No. PCT/EP2019/051614 § 371(c)(1), (2) Date Jul. 21, 2020, PCT Pub. No. WO2019/149593, PCT Pub. Date Aug. 8, 2019.
Claims priority of application No. 102018201622.4 (DE), filed on Feb. 2, 2018.
Prior Publication US 2021/0079493 A1, Mar. 18, 2021
Int. Cl. C22C 38/04 (2006.01); C21D 9/52 (2006.01); C21D 6/00 (2006.01); C21D 8/12 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/06 (2006.01); C22C 38/14 (2006.01); H01F 1/147 (2006.01); C21D 9/46 (2006.01)

CPC C21D 9/52 (2013.01) [C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/1222 (2013.01); C21D 8/1233 (2013.01); C21D 8/1261 (2013.01); C21D 9/46 (2013.01); C22C 38/001 (2013.01); C22C 38/004 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/14 (2013.01); H01F 1/147 (2013.01); C21D 2201/05 (2013.01)]

9 Claims

1. A process for producing a non-grain-oriented electrical steel strip or sheet, comprising:

(A) Providing a hot-rolled strip containing, apart from iron and unavoidable impurities in % by weight:

up to 0.0040 of C,

from 0.1500 to 0.3000 of Mn,

from 2.300 to 2.700 of Si,

from 0.3000 to 0.8000 of Al,

up to 0.0400 of P,

up to 0.0035 of S,

up to 0.0070 of N and

up to 0.0070 of Ti,

(B) Cold rolling of the hot-rolled strip to give a cold-rolled strip;

(C) Final heat treating of the cold-rolled strip from step (B) at a temperature of from 750 to 950° C. to give the non-grain-oriented electrical steel strip or sheet;

(D) Subsequent to the final heat treating, cooling the non-grain-oriented electrical strip or sheet to ambient temperature;

(E) Subsequent to the cooling from step (D), reference heat treating of the non-grain-oriented electrical steel strip or sheet at a temperature of from 600 to 1000° C.; and

subsequent to the final heat treating of step (C) and prior to the reference heat treating of step (E), performing a parting process including selected from one of cutting, stamping and laser cutting on the non-grain-oriented electrical strip or sheet, wherein the reference heat treating of step (E) repairs damage arising at parting edges on the non-grain-oriented electrical strip or sheet resulting from the parting process;

wherein a yield point Rp_0.2in the non-grain-oriented electrical steel strip or sheet subsequent to step (E) is 300 to 399 N/mm²;

wherein a ratio of magnetic loss P_1.0/50of the non-grain-oriented electrical strip or sheet subsequent to the final heat treating of step (C) to magnetic loss P_1.0/50of the non-grain-oriented electrical strip or sheet subsequent to the reference heat treating of step (E) is at least 1.30.