EP 3428302 A1 20190116 - HOT-DIP GALVANIZED STEEL SHEET WITH SUPERIOR BAKE HARDENABILITY AND AGING RESISTANCE, AND MANUFACTURING METHOD THEREOF
Title (en)
HOT-DIP GALVANIZED STEEL SHEET WITH SUPERIOR BAKE HARDENABILITY AND AGING RESISTANCE, AND MANUFACTURING METHOD THEREOF
Title (de)
FEUERVERZINKTES STAHLBLECH MIT AUSGEZEICHNETER EINBRENNHÄRTBARKEIT UND ALTERUNGSBESTÄNDIGKEIT UND HERSTELLUNGSVERFAHREN DAFÜR
Title (fr)
TÔLE D'ACIER GALVANISÉE PAR IMMERSION À CHAUD AYANT UNE APTITUDE AU DURCISSEMENT PAR CUISSON ET UNE RÉSISTANCE AU VIEILLISSEMENT SUPÉRIEURES, ET PROCÉDÉ PERMETTANT DE LA FABRIQUER
Publication
Application
Priority
- KR 20160027834 A 20160308
- KR 2017002417 W 20170307
Abstract (en)
Disclosed are a cold-rolled steel sheet having excellent bake hardenability and aging resistance, and a manufacturing method thereof. The cold-rolled steel sheet comprises, by weight %, 0.02-0.08% of C; 1.3-2.1% of Mn; 0.3% or less (excluding 0%) of Si; 1.0% or less (excluding 0%) of Cr; 0.1% or less (excluding 0%) of P; 0.01% or less (excluding 0%) of S; 0.01% or less (excluding 0%) of N; and 0.01-0.06% of sol.Al; at least one selected from the group consisting of 0.2% or less (excluding 0%) of Mo and 0.003% or less (excluding 0%) of B; and the balance being Fe and other inevitable impurities, wherein the steel sheet contains, as a microstructure thereof, 90-99% of ferrite and 1-10% of martensite in an area fraction, wherein a ratio (a/b) of an average carbon concentration a in the martensite and an average carbon concentration b in the ferrite located in an imaginary circle having a major axis of the martensite as a diameter, at a point of the sheet thickness of 1/4 t is 1.4 or less, and a ratio (d/c) of an average manganese concentration c in the martensite and an average manganese concentration d in the ferrite located in an imaginary circle having a major axis of the martensite as a diameter, at a point of a sheet thickness of 1/4 t is 0.9 or less.
IPC 8 full level
C22C 38/18 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/22 (2006.01); C22C 38/32 (2006.01); C22C 38/38 (2006.01); C23C 2/06 (2006.01)
CPC (source: EP US)
C21D 6/002 (2013.01 - EP US); C21D 6/005 (2013.01 - EP US); C21D 6/008 (2013.01 - EP US); C21D 8/0273 (2013.01 - EP US); C21D 8/0405 (2013.01 - EP US); C21D 8/0426 (2013.01 - EP US); C21D 8/0436 (2013.01 - EP US); C21D 8/0473 (2013.01 - EP US); C21D 9/48 (2013.01 - EP US); C22C 38/001 (2013.01 - EP US); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP US); C22C 38/06 (2013.01 - EP US); C22C 38/18 (2013.01 - EP US); C22C 38/22 (2013.01 - EP US); C22C 38/32 (2013.01 - EP US); C22C 38/38 (2013.01 - EP US); C23C 2/0224 (2022.08 - EP US); C23C 2/06 (2013.01 - EP US); C23C 2/29 (2022.08 - EP US); C21D 8/0226 (2013.01 - EP US); C21D 8/0236 (2013.01 - EP US); C21D 9/46 (2013.01 - EP US); C21D 2211/005 (2013.01 - EP US); C21D 2211/008 (2013.01 - EP 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
DOCDB simple family (publication)
EP 3428302 A1 20190116; EP 3428302 A4 20190123; CN 108779537 A 20181109; JP 2019512600 A 20190516; KR 101767818 B1 20170811; US 2019071746 A1 20190307; WO 2017155263 A1 20170914
DOCDB simple family (application)
EP 17763524 A 20170307; CN 201780016428 A 20170307; JP 2018546894 A 20170307; KR 20160027834 A 20160308; KR 2017002417 W 20170307; US 201716079641 A 20170307