Casting process for aluminum alloys
AssigneeAlcan Rhenalu
InventorsTimothy WARNER, Christophe Sigli, Cedric Gasqueres, Armelle Danielou
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Abstract
The invention relates to a wrought product such as an extruded, rolled and/or forged aluminum alloy-based product, comprising, in weight %: Cu: 3.0-3.9; Li: 0.8-1.3; Mg: 0.6-1.0; Zr: 0.05-0.18; Ag: 0.0-0.5; Mn: 0.0-0.5; Fe+Si≦0.20; Zn≦0.15; at least one element from among: Ti: 0.01-0.15; Sc: 0.05-0.3; Cr: 0.05-0.3; Hf: 0.05-0.5; other elements ≦0.05 each and ≦0.15 total, remainder aluminum. The invention also relates to the process for producing said product. The products according to the invention are particularly useful in the production of thick aluminum products intended for producing structural elements in the aeronautical industry.
Claims20
An aluminum-based wrought product that is optionally extruded, rolled and/or forged, said product comprising, in weight %:
- Cu:
- 3.0-3.9;
- Li:
- 0.8-1.3;
- Mg:
- 0.6-1.0;
- Zr:
- 0.05-0.18;
- Ag:
- 0.0-0.5;
- Mn:
- 0.0-0.5;
- Fe+Si≦0.20;
- Zn≦0.15;
- at least one element selected from the group consisting of:
- Ti:
- 0.01-0.15;
- Sc:
- 0.05-0.3;
- Cr:
- 0.05-0.3;
- Hf:
- 0.05-0.5;
- other elements ≦0.05 each and ≦0.15 total, remainder aluminum.
A process for producing an extruded, rolled and/or forged aluminum alloy-based product, comprising:
- a) producing an aluminum-based liquid metal bath comprising 3.0 to 3.9% by weight Cu, 0.8 to 1.3% by weight Li, 0.6 to 1.0% by weight Mg, 0.05 a 0.18% by weight Zr, 0.0 to 0.5% by weight Ag, 0.0 to 0.5% by weight Mn, at most 0.20% by weight Fe+Si, at most 0.15% by weight Zn, at least one element selected from the group consisting of Cr, Sc, Hf and Ti, the amount of said element, if selected, being from 0.05 to 0.3% by weight for Cr and for Sc, 0.05 to 0.5% by weight for Hf and 0.01 to 0.15% by weight for Ti, the other elements at most 0.05% by weight each, and 0.15% by weight in total, remainder aluminum;
- b) casting a raw product from said liquid metal bath;
- c) homogenizing said raw product at a temperature of from 450° C. to 550° for a period of from 5 to 60 hours;
- d) hot and optionally cold working said raw product into an extruded, rolled and/or forged product;
- e) solution treating said product at from 490 to 530° C. for 15 min to 8 hours and quenching;
- f) stretching said product in a controlled manner with a permanent set of 1 to 6%;
- g) aging said product, comprising heating at a temperature of from 130 to 170° C. for 5 to 100 hours so as to obtain a yield strength close to peak.
A method for improving the compromise between properties of static mechanical strength and properties of damage tolerance and thermal stability, while having a low density, of aluminum-copper-lithium alloy products comprising increasing the magnesium content in said alloy above what has been previously specified for said alloy and optionally subjecting said alloy to near-peak aging.
Dependencies are inferred from the claim text.