Patent US3687756A successfully refreshed from Google Patents.
EP0090583A2
Expired / Lapsed
EP
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Heat treatment of aluminium alloys
Assignee: Rio Tinto Alcan International Ltd
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Filing: 1983-03-22
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Granted: —
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Expires: 2003-03-22
Abstract
Abstract Aluminium alloys containing lithium and copper and/or magnesium as principal alloying constituents are homogenized at 530°C or above to take into solution as-cast intermetallic phases which do not fully go into solution at conventional homogenization temperatures for this class of alloy. Preferably the alloy ingots are slowly heated at rates not exceeding 50°C/ hour up to a final homogenization temperature in the region of 550°-560°C and are then allowed to cool without prolonged holding at temperature.
Inventors
- 👤 David John Field
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 09:23
CPC Classifications
C; C22; C22C; C22C21/00; C22C21/06; C22C21/12; C22F; C22F1/00; C22F1/04; C22F1/05; C22F1/057
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
153 words
A procedure for the homogenisation of ingots of ternary and quaternary alloys in the system Al-Li-Cu-Mg which comprises heating the alloy to a temperature of at least 530°C, but below the melting point of solid intermetallic phases contained therein and maintaining the alloy at a temperature above 530°C until such phases have entered solid solution in the alloy and then cooling the ingot, said ingot being formed of an alloy in one of the following composition ranges - (1) 1-3% Li, 0.5-2% Cu, 0.02-2% Mg. (2) 1-3% Li, 2-4% Mg, below 0.1% Cu and having a total Li + Mg content of no more than 6.0%. (3) 1-3% Li, 0.5-4% Cu and up to 0.2% Mg the remainder of each of the above being Al, containing other elements in amounts in the following ranges: (Zr + Mn + Cr) 0-0.6%; Fe + Si 0-0.4%; impurities up to 0.15% total (up to 0.05% each).
Claim 2
Dependent Claim
153 words
A procedure for the homogenisation of ingots of ternary and quaternary alloys in the system Al-Li-Cu-Mg which comprises heating the alloy to a temperature of at least 530°C, but below the melting point of solid intermetallic phases contained therein and maintaining the alloy at a temperature above 530°C until such phases have entered solid solution in the alloy and then cooling the ingot, said ingot being formed of an alloy in one of the following composition ranges - (1) 1-3% Li, 0.5-2% Cu, 0.02-2% Mg. (2) 1-3% Li, 2-4% Mg, below 0.1% Cu and having a total Li + Mg content of no more than 6.0%. (3) 1-3% Li, 0.5-4% Cu and up to 0.2% Mg the remainder of each of the above being Al, containing other elements in amounts in the following ranges: (Zr + Mn + Cr) 0-0.6%; Fe + Si 0-0.4%; impurities up to 0.15% total (up to 0.05% each).
Claim 3
Dependent Claim
29 words
A procedure according to claim 1 in which the ingot temperature is raised at a rate not exceeding 50°C/hr during the heating of the ingot from 400°C to 530°C.
Claim 4
Dependent Claim
27 words
A procedure according to claim 1 in which the ingot temperature is raised at a temperature not exceeding 50°C/hr during the heating of the ingot from 200°C.
Claim 5
Dependent Claim
52 words
A procedure according to claim 1 in which the alloy has the composition 1-3% Li 0.5-2% Cu 0.2-2% Mg up to 0.4% Fe + Si up to 0.6% (Mn + Cr + Zr) others (impurities) up to 0.15% total (up to 0.05% each) comprising heating the alloy to a temperature above 540°C.
Claim 6
Dependent Claim
24 words
A procedure according to claim 4 in which the alloy ingot is held at a temperature in the range of 540-550°C for 2-6 hours.
Claim 7
Dependent Claim
33 words
A procedure according to claim 4 in which the ingot is heated to a temperature of at least 550°C from 530°C at a rate not exceeding 50°C/hour and is then allowed to cool.
Claim 8
Dependent Claim
30 words
A procedure according to claim 4, 5 or 6 in which the ingot is heated to 530°C from a temperature not exceeding 450°C at a rate not exceeding 50 C/hr.
References Cited (Backward Citations)
No citation records indexed.
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