EP 1412548 A1 20040428 - MULTI-PHASE STEEL SHEET EXCELLENT IN HOLE EXPANDABILITY AND METHOD OF PRODUCING THE SAME
Title (en)
MULTI-PHASE STEEL SHEET EXCELLENT IN HOLE EXPANDABILITY AND METHOD OF PRODUCING THE SAME
Title (de)
MEHRPHASEN-STAHLBLECH MIT VERBESSERTER TIEFZIEHFÄHIGKEIT UND VERFAHREN ZU SEINER HERSTELLUNG
Title (fr)
TOLE D'ACIER A PLUSIEURS PHASES PRESENTANT UN TRES BON POUVOIR D'EXPANSION DE TROU ET PROCEDE POUR PRODUIRE CETTE TOLE D'ACIER
Publication
Application
Priority
- JP 0207568 W 20020725
- JP 2001224750 A 20010725
Abstract (en)
[origin: WO03010351A1] The present invention provides a steel sheet excellent in both a balance between strength and elongation and a balance between strength and hole expandability, in other words, a multi-phase steel sheet having an excellent balance between strength and hole expandability. The present invention is a multi-phase steel sheet excellent in hole expandability characterized in that: the steel sheet contains, as chemical components in mass, C: 0.03 to 0.15%, P: not more than 0.010%, S: not more than 0.003%, andeither one or both of Si and Al in a total amount of 0.5 to 4%, and one or more of Mn, Ni, Cr, Mo and Cu in a total amount of 0.5 to 4%, with the balance consisting of Fe and unavoidable impurities; the microstructure at a section of the steel sheet is composed of either one or both of retained austenite and martensite which account(s) for 3 to 30% in total in area percentage and the balance consisting of either one or both of ferrite and bainite; the maximum length of the crystal grains in the microstructure is not more than 10 microns; and the number of inclusions 20 microns or larger in size at a section of the steel sheet is not more than 0.3 piece per square millimeter.
IPC 1-7
IPC 8 full level
C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/58 (2006.01); C21D 8/02 (2006.01)
CPC (source: EP KR)
C22C 38/02 (2013.01 - EP); C22C 38/04 (2013.01 - EP); C22C 38/06 (2013.01 - EP KR); C21D 8/0226 (2013.01 - EP); C21D 2211/001 (2013.01 - EP); C21D 2211/002 (2013.01 - EP); C21D 2211/005 (2013.01 - EP); C21D 2211/008 (2013.01 - EP)
Citation (search report)
See references of WO 03010351A1
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
WO 03010351 A1 20030206; CN 1243844 C 20060301; CN 1535323 A 20041006; DE 60206771 D1 20060302; DE 60206771 T2 20060720; EP 1412548 A1 20040428; EP 1412548 B1 20051019; JP 2004536965 A 20041209; JP 4181036 B2 20081112; KR 100548117 B1 20060202; KR 20040013156 A 20040211; TW 567231 B 20031221
DOCDB simple family (application)
JP 0207568 W 20020725; CN 02814676 A 20020725; DE 60206771 T 20020725; EP 02751696 A 20020725; JP 2003515697 A 20020725; KR 20047001015 A 20020725; TW 91116465 A 20020724