EP 0577124 A3 19940921 - GRAIN ORIENTED ELECTRICAL STEEL SHEET HAVING HIGH MAGNETIC FLUX DENSITY AND ULTRA LOW IRON LOSS AND PROCESS FOR PRODUCING THE SAME
Title (en)
GRAIN ORIENTED ELECTRICAL STEEL SHEET HAVING HIGH MAGNETIC FLUX DENSITY AND ULTRA LOW IRON LOSS AND PROCESS FOR PRODUCING THE SAME
Publication
Application
Priority
- JP 17579092 A 19920702
- JP 20679592 A 19920803
- JP 22050092 A 19920819
- JP 28478792 A 19921022
- JP 30272892 A 19921112
- JP 34074692 A 19921221
Abstract (en)
[origin: EP0577124A2] A grain oriented electrical steel sheet having no significant glass film and having a high magnetic flux density and an excellent iron loss property, comprising, in terms of by weight, 2.5 to 4.5% of Si, the steel sheet having, as oxides on its surface, a glass film comprising 0.6 g/m<2> or less in total of forsterite and spinel composed of MgO, SiO2 and Al2O3 and an insulating coating having a thickness of 6 mu m or less, the face tension imparted on the surface of the steel sheet by the coating being in the range of from 0.5 to 2.0 kg/mm<2>. In the final box annealing of the steel sheet after primary recrystallization annealing, use is made of an annealing separator comprising 100 parts by weight of MgO and, added thereto, 2 to 30 parts by weight of at least one member selected from the group consisting of chlorides, carbonates, nitrates, sulfates and sulfides of Li, K, Bi, Na, Ba, Ca, Mg, Zn, Fe, Zr, Sr, Sn, Al, etc., and the heating in the final box annealing is effected in an atmosphere comprising N2 and H2 with the nitrogen content being 30% or more at a heating rate of 20 DEG C/hr or less, and a seam or spotty flaw is imparted at an angle of 45 to 90 DEG to the rolling direction of the steel sheet.
IPC 1-7
IPC 8 full level
C21D 8/12 (2006.01); H01F 1/147 (2006.01)
CPC (source: EP KR)
C21D 8/12 (2013.01 - KR); C21D 8/1283 (2013.01 - EP); H01F 1/14783 (2013.01 - EP); C21D 8/1222 (2013.01 - EP); C21D 8/1255 (2013.01 - EP); C21D 8/1272 (2013.01 - EP); C21D 8/1294 (2013.01 - EP)
Citation (search report)
- [A] US 4367100 A 19830104 - MILLER JR CLARENCE L & JP S5665983 A 19810604 - ALLEGHENY LUDLUM IND INC
- [A] US 3856568 A 19741224 - TANAKA O, et al & JP S5328375 B2 19780814
- [A] US 3671337 A 19720620 - KUMAI KO, et al & JP S4725250 B1
- [E] EP 0565029 A1 19931013 - NIPPON STEEL CORP [JP]
- [E] EP 0566986 A1 19931027 - NIPPON STEEL CORP [JP]
- [XP] EP 0525467 A2 19930203 - NIPPON STEEL CORP [JP]
- [X] EP 0488726 A2 19920603 - KAWASAKI STEEL CO [JP]
- [X] EP 0305966 A1 19890308 - NIPPON STEEL CORP [JP]
- [A] US 4032366 A 19770628 - CHOBY JR EDWARD G
- [A] FR 2445377 A1 19800725 - KAWASAKI STEEL CO [JP]
- [A] EP 0392534 A1 19901017 - NIPPON STEEL CORP [JP]
- [A] EP 0420238 A2 19910403 - NIPPON STEEL CORP [JP]
- [A] GB 1480514 A 19770720 - KAWASAKI STEEL CO
- [AD] DATABASE WPI Section Ch Week 7815, Derwent World Patents Index; Class M27, AN 78-27745A
- [AD] PATENT ABSTRACTS OF JAPAN vol. 8, no. 212 (C - 244) 27 September 1984 (1984-09-27)
- [A] PATENT ABSTRACTS OF JAPAN vol. 3, no. 142 (C - 65) 24 November 1979 (1979-11-24)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0577124 A2 19940105; EP 0577124 A3 19940921; EP 0577124 B1 20021016; DE 69332394 D1 20021121; DE 69332394 T2 20030612; KR 940005812 A 19940322; KR 960009170 B1 19960716
DOCDB simple family (application)
EP 93110517 A 19930701; DE 69332394 T 19930701; KR 930012299 A 19930701