US 5,292,386 AGranted

Process for the manufacture of aluminum sheets

AssigneesHoogovens Aluminium GmbH, Duetsche Forschungsanstalt fur Luft und Raumfahrt DLR

InventorsWerner Schelb, Manfred Peters, Karl Welpmann

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Abstract

In order to achieve damage-tolerant properties and sufficient isotropy of aluminum alloys, particularly of type AlLi 8090, subsequent especially to hot-forming of a bar of said aluminum alloy there is interposed a solution heat treatment and quenching, followed by working and subsequent intermediate annealing within a temperature range of from 250.degree. to 475.degree. C. for a period of from 1 to 85 hours. The intermediate annealing is followed by cold forming and subsequent solution heat treatment with the additional purpose of recrystallization, whereupon the recrystallized material is especially cold-formed to a degree of deformation of only up to 8%. Thereafter the sheets having a sheet thickness of from 0.5 to 10 mm are subjected to artificial aging.

Claims8

Dependent claims

A process of manufacturing sheets of an aluminum-lithium alloys of thickness between about 0.5 and 10 mm, said process comprising the steps of:

(a) shaping a bar made from said alloy by hot rolling into a sheet, strip or other similar semifinished product;
(b) subjecting said semifinished product to solution heat treatment;
(c) quenching said solution heat-treated semifinished product;
(d) cold rolling the quenched semifinished product at a reduction of between about 2% to 60%;
(e) subjecting the reduced product to intermediate annealing in a temperature range of about 250.degree. to 475.degree. for a period of 1to 85 hours;
(f) subjecting the annealed semifinished product to cold rolling at a reduction between about 40% and 90%;
(g) solution heat treating the cold worked semifinished product at a temperature at which recrystallization occurs;
(h) quenching said solution-treated semifinished product;
(i) working said quenched semifinished product at a reduction of up to about 8% by cold stretching and/or cold stretch-forming to provide a finished product;
and
(j) aging said finished product.

8 more elements

Dependencies are inferred from the claim text.