EP 0750049 A1 19961227 - Ferritic steel and its manufacture and use
Title (en)
Ferritic steel and its manufacture and use
Title (de)
Ferritischer Stahl und Verfahren zu seiner Herstellung und Verwendung
Title (fr)
Acier ferritique; sa fabrication et son utilisation
Publication
Application
Priority
- DE 19521836 A 19950616
- DE 19605696 A 19960216
Abstract (en)
A ferritic steel contains (wt. %) 0.05-0.3 C, 0.8-3.0 Mn, 0.4-2.5 Al, < 0.2 Si, < 0.08 P, < 0.05 S, balance Fe and unavoidable impurities. Ceq = %C + <1>/20%Mn + <1>/20%Cr + <1>/15%Mo = 0.1-0.325. Al ≥ 7.6Ceq - 0.36 wt. %. Also claimed is a process for producing the above steel having high strength, good cold workability and surface quality in the hot-rolled state and good cold-rollability with a structure consisting predominantly of pre-eutectic ferrite and smaller proportions of martensite and/or bainite and/or residual austenite, which is cast into a blank, hot rolled with a starting temperature of above 1000 degrees C and an end temperature (ET) in the region Ar3 - 50 degrees C < ET < Ar3 + 100 degrees C, cooled from the ET at a rate of 15-70 K/s to the coiling temperature which is below 500 degrees C, and coiled.
Abstract (de)
Die Erfindung betrifft einen Dualphasenstahl mit überwiegend polygonal-ferritischem Gefüge, in dem eine kohlenstoffangereicherte perlitfreie harte zweite Phase eingelagert ist, die aus Martensit und/oder Bainit und/oder Restaustenit besteht, mit hoher Festigkeit und guter Umformbarkeit sowie verbesserter Oberflächenqualität nach einer Warmverformung, ein Verfahren zu seiner Herstellung und Verwendung. <IMAGE>
IPC 1-7
IPC 8 full level
C21D 8/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01)
CPC (source: EP)
C21D 8/0226 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C21D 2211/001 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01)
Citation (applicant)
Citation (search report)
- [X] BE 899253 A 19840716 - GIELEN PAUL M E L
- [A] FR 2253841 A1 19750704 - CENTRO SPERIMENT METALLURG [IT]
- [A] US 4316753 A 19820223 - KANEKO KUNISHIGE, et al
- [A] EP 0586704 A1 19940316 - NIPPON STEEL CORP [JP]
- [PX] US 5470529 A 19951128 - NOMURA SHIGEKI [JP], et al
- [X] PATENT ABSTRACTS OF JAPAN vol. 018, no. 668 (C - 1289) 16 December 1994 (1994-12-16)
- [X] PATENT ABSTRACTS OF JAPAN vol. 017, no. 373 (C - 1083) 14 July 1993 (1993-07-14)
Designated contracting state (EPC)
AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
EP 0750049 A1 19961227; AR 002501 A1 19980325; BR 9608672 A 19990504; CA 2224817 A1 19970103; CN 1190997 A 19980819; CZ 402497 A3 19980617; HU P9801908 A2 19981130; HU P9801908 A3 19981228; MX 9710230 A 19980329; PL 324555 A1 19980608; TR 199701720 T1 19980521; WO 9700332 A1 19970103
DOCDB simple family (application)
EP 96107884 A 19960517; AR 10318196 A 19960614; BR 9608672 A 19960601; CA 2224817 A 19960601; CN 96195583 A 19960601; CZ 402497 A 19960601; EP 9602383 W 19960601; HU P9801908 A 19960601; MX 9710230 A 19960601; PL 32455596 A 19960601; TR 9701720 T 19960601