US 12,146,202 B2
Process for manufacturing thin sheets made of 7XXX aluminum alloy suitable for shaping and assembly
David Barbier, Grenoble (FR); Jean-Philippe Masse, Grenoble (FR); Olivier Rebuffet, Grenoble (FR); and Laurent Cervi, Saint Jean de Moirans (FR)
Assigned to CONSTELLIUM NEUF-BRISACH, Biesheim (FR)
Appl. No. 17/259,341
Filed by CONSTELLIUM NEUF-BRISACH, Biesheim (FR)
PCT Filed Jul. 11, 2019, PCT No. PCT/FR2019/051739
§ 371(c)(1), (2) Date Jan. 11, 2021,
PCT Pub. No. WO2020/016506, PCT Pub. Date Jan. 23, 2020.
Claims priority of application No. 1856613 (FR), filed on Jul. 17, 2018.
Prior Publication US 2021/0292861 A1, Sep. 23, 2021
Int. Cl. C22F 1/053 (2006.01); B21D 22/02 (2006.01); C21D 8/02 (2006.01); C21D 9/46 (2006.01); C22C 21/10 (2006.01)
CPC C21D 8/0226 (2013.01) [B21D 22/022 (2013.01); C21D 8/0236 (2013.01); C21D 9/46 (2013.01); C22C 21/10 (2013.01); C22F 1/053 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A process for manufacturing a rolled product based on an aluminum alloy, optionally for the automotive industry wherein, successively,
a) making a bath of liquid metal from an aluminum-based alloy comprising 4 to 7% by weight of Zn, 1.0 to 3.0% by weight of Cu, 1.5 to 3.5% by weight of Mg, at most 0.50% by weight of Fe, at most 0.40% by weight of Si, at least one element chosen from Zr, Mn, Cr, Sc, Hf and Ti, the amount of said element, if it is chosen, being 0.05 to 0.18% by weight for Zr, 0.1 to 0.6% by weight for Mn, 0.05 to 0.3% by weight for Cr, 0.02 to 0.2% by weight for Sc, 0.05 to 0.5% by weight for Hf and 0.005 to 0.15% by weight for Ti, the other elements being at most 0.05% by weight each and 0.15% by weight in total, the remainder being aluminum,
b) casting a rolling ingot from the bath of liquid metal,
c) optionally, the rolling ingot is homogenized,
d) hot rolling and optionally cold-rolling the rolling ingot to give a sheet,
e) solution heat treating and quenching the sheet,
f) optionally, leveling the sheet and/or subjecting to controlled traction with cumulative deformation of at least 0.5% and less than 3%,
g) performing heat treatment wherein the sheet reaches a temperature of between 6° and 120° C. for 8 to 16 hours,
h) aging the sheet for at least 30 days at ambient temperature.