US 11,697,866 B2
Manufacturing process for obtaining high strength extruded products made from 6xxx aluminium alloys
Alexis Skubich, Zurich (CH); and Martin Jarrett, Oxfordshire (GB)
Assigned to CONSTELLIUM SINGEN GmbH, Singen (DE)
Appl. No. 15/100,793
Filed by CONSTELLIUM VALAIS SA (AG-LTD), Sierre (CH)
PCT Filed Nov. 27, 2014, PCT No. PCT/EP2014/003170
§ 371(c)(1), (2) Date Jun. 1, 2016,
PCT Pub. No. WO2015/086116, PCT Pub. Date Jun. 18, 2015.
Claims priority of application No. 13005757 (EP), filed on Dec. 11, 2013.
Prior Publication US 2016/0304994 A1, Oct. 20, 2016
This patent is subject to a terminal disclaimer.
Int. Cl. C22F 1/05 (2006.01); C22C 21/08 (2006.01); C22C 21/02 (2006.01); C22F 1/043 (2006.01); C22F 1/04 (2006.01); C22F 1/047 (2006.01); B21C 23/00 (2006.01); B22D 21/00 (2006.01)
CPC C22C 21/02 (2013.01) [B21C 23/002 (2013.01); B22D 21/007 (2013.01); C22C 21/08 (2013.01); C22F 1/04 (2013.01); C22F 1/043 (2013.01); C22F 1/047 (2013.01); C22F 1/05 (2013.01)] 14 Claims
 
1. A manufacturing process for obtaining extruded products made from a 6xxx aluminium alloy, wherein said manufacturing process comprises:
a) homogenizing a billet cast from said aluminium alloy and then cooling the billet down to room temperature;
b) heating the homogenized cast billet;
c) extruding said billet through a die to form at least a solid or hollow extruded product;
d) quenching with a water quench the extruded product down to room temperature;
f) ageing the extruded product without applying on the extruded product any separate post-extrusion solution heat treatment;
wherein said 6xxx aluminium alloy comprises Si: 0.3-1.7 wt. %; Mg: 0.1-1.4 wt. %; Mn: 0.55-1.4%, and at least one dispersoid element comprising Cr (0.05-0.4 wt. %) or Zr (0.05-0.25 wt %), the rest being aluminium and inevitable impurities; and
wherein:
i) the heating b) is a solution heat treatment where:
b1) the cast billet is heated to a temperature between Ts-15° C. and Ts, wherein Ts is the solidus temperature of said aluminium alloy and is at least 575° C.;
b2) the billet is cooled until billet mean temperature reaches a value between 400° C. and 480° C. while ensuring billet surface never goes below 400° C.;
ii) the billet thus cooled is immediately extruded in c after the end of b2.