EP 4375391 A1 20240529 - HIGH-STRENGTH STEEL SHEET HAVING EXCELLENT HOLE EXPANDABILITY AND DUCTILITY AND MANUFACTURING METHOD THEREFOR
Title (en)
HIGH-STRENGTH STEEL SHEET HAVING EXCELLENT HOLE EXPANDABILITY AND DUCTILITY AND MANUFACTURING METHOD THEREFOR
Title (de)
HOCHFESTES STAHLBLECH MIT HERVORRAGENDER LOCHDEHNBARKEIT UND DUKTILITÄT UND HERSTELLUNGSVERFAHREN DAFÜR
Title (fr)
FEUILLE D'ACIER À HAUTE RÉSISTANCE DOTÉE D'EXCELLENTES CAPACITÉ D'EXPANSION DE TROU ET DUCTILITÉ ET PROCÉDÉ DE FABRICATION ASSOCIÉ
Publication
Application
Priority
- KR 20210094848 A 20210720
- KR 2022008874 W 20220622
Abstract (en)
The present invention relates to steel suitable as a material for automobiles and, specifically, to a high-strength steel sheet having excellent hole expandability and ductility, and a manufacturing method therefor. The high-strength steel sheet of the present invention has a microstructure comprising a hard phase and a soft phase, wherein a martensite phase, which is the hard phase, is evenly distributed in a recrystallized ferrite matrix through optimized cold-rolling and annealing processes, and a nonequilibrium ferrite phase is introduced at the interface between the hard phase and the soft phase so as to increase the crack resistance during processing.
IPC 8 full level
C22C 38/38 (2006.01); B21C 47/02 (2006.01); C21D 8/02 (2006.01); C22C 38/00 (2006.01); C22C 38/22 (2006.01); C22C 38/26 (2006.01); C22C 38/28 (2006.01); C22C 38/32 (2006.01)
CPC (source: EP KR US)
B21C 47/02 (2013.01 - KR); C21D 1/18 (2013.01 - US); C21D 1/19 (2013.01 - EP); C21D 1/84 (2013.01 - US); C21D 6/002 (2013.01 - US); C21D 6/005 (2013.01 - US); C21D 6/008 (2013.01 - US); C21D 8/0205 (2013.01 - EP US); C21D 8/0226 (2013.01 - EP KR US); C21D 8/0236 (2013.01 - EP KR US); C21D 8/0263 (2013.01 - EP US); C21D 8/0273 (2013.01 - EP KR); C21D 9/0062 (2013.01 - EP); C21D 9/46 (2013.01 - EP US); C22C 38/001 (2013.01 - KR US); C22C 38/002 (2013.01 - US); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP US); C22C 38/06 (2013.01 - US); C22C 38/12 (2013.01 - EP); C22C 38/14 (2013.01 - EP); C22C 38/22 (2013.01 - EP KR); C22C 38/26 (2013.01 - EP KR US); C22C 38/28 (2013.01 - EP KR US); C22C 38/32 (2013.01 - EP KR US); C22C 38/38 (2013.01 - EP KR US); C21D 2211/005 (2013.01 - EP KR US); C21D 2211/008 (2013.01 - EP KR US)
Designated contracting state (EPC)
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated extension state (EPC)
BA ME
Designated validation state (EPC)
KH MA MD TN
DOCDB simple family (publication)
EP 4375391 A1 20240529; CN 117043382 A 20231110; JP 2024527419 A 20240724; KR 20230014121 A 20230130; US 2024287639 A1 20240829; WO 2023003188 A1 20230126
DOCDB simple family (application)
EP 22846060 A 20220622; CN 202280017433 A 20220622; JP 2024502609 A 20220622; KR 20210094848 A 20210720; KR 2022008874 W 20220622; US 202218578672 A 20220622