EP 3728654 A1 20201028 - COLD-ROLLED FLAT STEEL PRODUCT HAVING METAL ANTI-CORROSION LAYER AND METHOD FOR PRODUCING SAME
Title (en)
COLD-ROLLED FLAT STEEL PRODUCT HAVING METAL ANTI-CORROSION LAYER AND METHOD FOR PRODUCING SAME
Title (de)
KALTGEWALZTES STAHLFLACHPRODUKT MIT METALLISCHER KORROSIONSSCHUTZSCHICHT UND VERFAHREN ZUR HERSTELLUNG EINES SOLCHEN
Title (fr)
PRODUIT EN ACIER PLAT LAMINÉ À FROID PRÉSENTANT UNE COUCHE MÉTALLIQUE DE PROTECTION CONTRE LA CORROSION ET PROCÉDÉ POUR LA FABRICATION D'UN TEL ACIER
Publication
Application
Priority
- DE 102017223633 A 20171221
- EP 2018085664 W 20181218
Abstract (en)
[origin: WO2019121793A1] The invention describes a method for producing a cold-rolled flat steel product having a metal anti-corrosion layer. The method comprises the work steps: melting a steel melt which contains, in addition to iron and unavoidable impurities, (in wt.%): C: 0.01-0.35%, Mn: 1-4%, Si: 0.5-2.5%, Nb: up to 0.1%, Ti: 0.015-0.1%, P: up to 0.1%, Al: up to 0.15%, S: up to 0.01%, N: up to 0.1%, and optionally one or more elements from the group of rare earth metals, Mo, Cr, Zr, V, W, Co, Ni, B, Cu, Ca, with rare earth metals: up to 0.2%, Mo: up to 1%, Cr: up to 3%, Zr: up to 1%, V: up to 1%, W: up to 1%, Co: up to 1%, Ni: up to 2%, B: up to 0.1%, Cu: up to 3%, Ca: up to 0.015%; casting the steel melt to form a semi-finished product; hot-rolling the semi-finished product to form a hot strip, wherein the hot-rolling temperature is 820–1000°C; winding the hot strip to form a coil, wherein the winding temperature is in the range between room temperature and 750°C; annealing the hot strip at an annealing temperature of more than 530°C and up to 950°C for an annealing duration of 1-50 hours; cold-rolling the annealed hot strip to form a cold-rolled flat steel product in one or more stages with a total cold-rolling degree of at least 45%; final annealing of the cold-rolled flat steel product at a final annealing temperature of 650–920°C for an annealing duration of 30-1500 seconds, wherein as a result of the final annealing of the cold-rolled flat steel product, an Si enrichment layer is created between a surface and a base material of the cold-rolled and finally-annealed flat steel product, the maximum Si content of which is higher by a factor of between 3 and 8 than the Si content of the base material and which has a depth of between 10 nm and 1 µm; and applying a zinc-based metal anti-corrosion layer by means of electrolytic galvanising or hot dip galvanising of the cold-rolled and finally-annealed flat steel product.
IPC 8 full level
C21D 6/00 (2006.01); B21B 1/22 (2006.01); B21B 1/24 (2006.01); B21B 1/26 (2006.01); B21B 1/28 (2006.01); C21D 1/26 (2006.01); C21D 7/02 (2006.01); C21D 7/10 (2006.01); C21D 8/02 (2006.01); C21D 8/04 (2006.01); C21D 9/46 (2006.01); C21D 9/48 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01); C23C 2/00 (2006.01); C23G 1/08 (2006.01); C25F 1/06 (2006.01)
CPC (source: EP US)
C21D 8/0226 (2013.01 - US); C21D 8/0236 (2013.01 - US); C21D 8/0263 (2013.01 - US); C21D 8/0273 (2013.01 - US); C21D 8/0426 (2013.01 - EP); C21D 8/0436 (2013.01 - EP); C21D 8/0463 (2013.01 - EP); C21D 8/0473 (2013.01 - EP); C21D 9/48 (2013.01 - EP); C22C 38/001 (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 US); C22C 38/20 (2013.01 - US); C22C 38/26 (2013.01 - US); C22C 38/30 (2013.01 - US); C22C 38/40 (2013.01 - US); C23C 2/06 (2013.01 - EP US); C23C 2/26 (2013.01 - EP US); C23C 6/00 (2013.01 - EP); C25D 3/22 (2013.01 - US); C25F 1/06 (2013.01 - EP); C23G 1/08 (2013.01 - EP); C25D 3/22 (2013.01 - EP)
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)
DE 102017223633 A1 20190627; EP 3728654 A1 20201028; US 11473160 B2 20221018; US 2020325552 A1 20201015; WO 2019121793 A1 20190627
DOCDB simple family (application)
DE 102017223633 A 20171221; EP 18826307 A 20181218; EP 2018085664 W 20181218; US 201816956301 A 20181218