US4840683A
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Al-Cu-Li-Mg alloys with very high specific mechanical strength
Assignee: Cegedur Societe de Transformation de lAluminium Pechiney SA
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Filing: 1988-02-16
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Granted: 1989-06-20
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Expires: 2008-02-16
Abstract
Abstract The invention relates to aluminum based alloys essentially containing Cu, Li and Mg, which have very high specific mechanical strength and can be used particularly to obtain heat treated articles of complex shapes. The analyses are as follows (as % by weight): Cu 2.4 to 3.5%, Li 1.9 to 2.7%; Mg from 0 to 0.8%; and up to: 0.20% Fe; 0.10% Si; 1% Mn; 0.30% Cr; 0.2% Zr; 0.1% Ti 0.02% Be preferably with the following limitation: 4.8</=% Cu+% Li+% (Mg/2)</=6.0. In the treated state the alloys have very high specific mechanical strength (Vickers hardness/density>70), even in the absence of any plastic deformation between quench and temper, thus justifying their use inter alia for components of complex shapes such as cast or stamped parts.
Inventors
- 👤 Bruno Dubost
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:26
CPC Classifications
C; C22; C22C; C22C21/00; C22C21/12; C22F; C22F1/00; C22F1/04
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
71 words
A heat treated and aged aluminium based alloy of very high specific mechanical strength, consisting essentially of (as % by weight): Cu from 2.4 to 3.5% Li from 1.9 to 2.7% Mg from about 0.26 to 0.8% Fe≦0.20% Si≦0.10% Mn from 0 to 1% Cr from 0 to 0.30% Zr from 0 to 0.20% Ti from 0 to 0.10% Be from 0 to 0.02% Other substances (impurities) each<0.05% total<0.15% remainder Al.
Claim 2
Dependent Claim
71 words
A heat treated and aged aluminium based alloy of very high specific mechanical strength, consisting essentially of (as % by weight): Cu from 2.4 to 3.5% Li from 1.9 to 2.7% Mg from about 0.26 to 0.8% Fe≦0.20% Si≦0.10% Mn from 0 to 1% Cr from 0 to 0.30% Zr from 0 to 0.20% Ti from 0 to 0.10% Be from 0 to 0.02% Other substances (impurities) each<0.05% total<0.15% remainder Al.
Claim 3
Dependent Claim
15 words
The alloy of claim 1, characterised in that it contains from 2.5 to 3.1% Cu.
Claim 4
Dependent Claim
18 words
The alloy of claim 1 or 2, characterised in that it contains from 2 to 2.5% of Li.
Claim 5
Dependent Claim
17 words
The alloy of claim 1, characterised in that it contains from about 0.26 to 0.5% of Mg.
Claim 6
Dependent Claim
12 words
The alloy of claim 1, characterised in that: 4.8≦% Cu+% Li+% Mg≦6.0
Claim 7
Dependent Claim
12 words
The alloy of claim 5, characterised in that: 5.0≦% Cu+% Li+% Mg≦5.8
Claim 8
Dependent Claim
18 words
The alloy of claim 1 or 2, characterised in that it contains a maximum of 0.10% of Fe.
Claim 9
Dependent Claim
16 words
The alloy of claim 1, characterised in that it contains a maximum of 0.06% of Si.
Claim 10
Dependent Claim
16 words
The alloy of claim 1, characterised in that it contains from 0.07 to 0.15% of Zr.
Claim 11
Dependent Claim
42 words
A method of making articles from the alloy of claim 1, comprising the steps of melting homogenizing, heat transforming, optionally cold transforming, solution anneal quenching and tempering, characterised in that homogenizing and/or solution anneal are effected at from 520° to 545° C.
Claim 12
Dependent Claim
33 words
The method of claim 10, characterised in that the homogenising time must be such that the size of the particles rich in Li and in Cu is from 0 to 5 μm inclusive.
Claim 13
Dependent Claim
33 words
The method of claim 10 or 11, characterised in that homogenisation proper is preceded by stages at approximately 500°, 515° and/or 528° C. with a view to avoiding incipient fusion of the alloy.
Claim 14
Dependent Claim
31 words
The method of claim 10 or 11, characterised in that tempering is carried out within the temperture range from 170° to 220° C. for a period of 8 to 48 hours.
Claim 15
Dependent Claim
22 words
The method of claim 10 or 11, characterised in that the product undergoes 1.5 to 5% plastic deformation between quenching and tempering.
Claim 16
Dependent Claim
29 words
The method of claim 12, characterized in that tempering is carried out within the temperature range from 170° to 220° C. for a period of 8 to 48 hours.
Claim 17
Dependent Claim
20 words
The method of claim 12, characterized in that the product undergoes 1.5 to 5% plastic deformation between quenching and tempering.
Claim 18
Dependent Claim
20 words
The method of claim 13, characterized in that the product undergoes 1.5 to 5% plastic deformation between quenching and tempering.
Claim 19
Dependent Claim
15 words
The alloy of claim 2, characterized in that it contains from 2.6 to 3% Cu.
References Cited (Backward Citations)
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