US4897126A
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Aluminum-lithium alloys having improved corrosion resistance
Assignee: Alcoa Corp
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Filing: 1988-06-30
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Granted: 1990-01-30
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Expires: 2008-06-30
Abstract
Abstract An aluminum base alloy wrought product having improved corrosion resistance in addition to combinations of strength and toughness. The product comprises 2.2 to 3.0 wt. % Li, 0.4 to 2.0 wt. % Mg, 0.2 to 1.6 wt. % Cu, 0 to 2.0 wt. % Mn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities and has the ability to develop improved combinations of strength and toughness in response to an aging treatment. Prior to an aging step, the product having imparted thereto a working effect equivalent to stretching so that after an aging step it has improved combinations of strength and toughness.
Inventors
- 👤 Philip E. Bretz
- 👤 Ralph R. Sawtell
- 👤 Warren H. Hunt, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:30
CPC Classifications
C; C22; C22C; C22C21/00; C22F; C22F1/00; C22F1/04
Claims Analysis
Total Claims: 54
Claim 1
Independent Claim
104 words
In a method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a lithium-containing aluminum base alloy product in a condition suitable for aging; (b) imparting to said product, prior to an aging step, a working effect equivalent to stretching said product greater than about 5% at room temperature; (c) selecting said alloy to be responsive to said working effect and controlling said working effect to provide improved combinations of fracture toughness and strength in response to aging; and (d) subjecting said product to an aging step.
Claim 2
Dependent Claim
104 words
In a method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a lithium-containing aluminum base alloy product in a condition suitable for aging; (b) imparting to said product, prior to an aging step, a working effect equivalent to stretching said product greater than about 5% at room temperature; (c) selecting said alloy to be responsive to said working effect and controlling said working effect to provide improved combinations of fracture toughness and strength in response to aging; and (d) subjecting said product to an aging step.
Claim 3
Dependent Claim
62 words
The method according to claim 1 wherein said product contains 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities.
Claim 4
Dependent Claim
16 words
The method according to claim 2 wherein the product contains 1.0 to 4.0 wt % Li.
Claim 5
Dependent Claim
16 words
The method according to claim 2 wherein the product contains 0.1 to 5.0 wt. % Cu.
Claim 6
Dependent Claim
41 words
The method according to claim 2 wherein the product contains 2.0 to 3.0 wt. % Li, 0.5 to 4.0 wt. % Cu, 0 to 3.0 wt. % Mg, 0 to 0.2 wt. % Zr and 0 to 1.0 wt. % Mn.
Claim 7
Dependent Claim
18 words
The method in accordance with claim 1 wherein the working effect is equivalent to stretching said body 4%.
Claim 8
Dependent Claim
20 words
The method in accordance with claim 1 wherein the working effect is equivalent to stretching said body 6 to 14%.
Claim 9
Dependent Claim
20 words
The method in accordance with claim 1 wherein the working effect is equivalent to stretching said body 6 to 8%.
Claim 10
Dependent Claim
31 words
The method in accordance with claim 1 including homogenizing a body of said alloy at a temperature in the range of 900° to 1050° F. prior to forming into said product.
Claim 11
Dependent Claim
28 words
The method in accordance with claim 1 including homogenizing a body of said alloy at least 1 hour at the homogenization temperature prior to forming into said product.
Claim 12
Dependent Claim
23 words
The method according to claim 1 including solution heat treating said product at a temperature in the range of 900° to 1050° F.
Claim 13
Dependent Claim
20 words
The method according to claim 1 including solution heat treating at least 30 seconds at the solution heat treating temperature.
Claim 14
Independent Claim
129 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body of an aluminum base alloy containing at least 0.5 wt. % lithium; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product an amount equivalent to stretching the wrought product greater than about 6% of its original length at room temperature; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 15
Independent Claim
129 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body of an aluminum base alloy containing at least 0.5 wt. % lithium; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product an amount equivalent to stretching the wrought product greater than about 6% of its original length at room temperature; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 16
Independent Claim
162 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a product containing 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt % max. Fe, 0 5 wt. % max. Si, the balance aluminum and incidental impurities; (b) imparting to said product, prior to an aging step, a working effect equivalent to stretching said product greater than about 5% in order that, after said aging step, said product can have improved combinations of strength and fracture toughness; (c) selecting said alloy to be responsive to said working effect and controlling said working effect to provide improved combinations of fracture toughness and strength in response to aging; and (d) subjecting said product to an aging step.
Claim 17
Independent Claim
162 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a product containing 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt % max. Fe, 0 5 wt. % max. Si, the balance aluminum and incidental impurities; (b) imparting to said product, prior to an aging step, a working effect equivalent to stretching said product greater than about 5% in order that, after said aging step, said product can have improved combinations of strength and fracture toughness; (c) selecting said alloy to be responsive to said working effect and controlling said working effect to provide improved combinations of fracture toughness and strength in response to aging; and (d) subjecting said product to an aging step.
Claim 18
Independent Claim
141 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing an aluminum base alloy product containing 1.0 to 4.0 wt. % Li, 0.5 to 4.0 wt. % Cu, 0 to 3.0 wt. % Mg, 0 to 0.2 wt. % Zr, 0 to 1.0 wt. % Mn, 0.5 wt. % max. Fe, and 0.5 wt. % max Si, the balance aluminum and incidental impurities; (b) imparting to said products a working effect equivalent to stretching said product an amount greater than about 6% at room temperature; (c) selecting said alloy to be responsive to said working effect and controlling said working effect to provide improved combinations of fracture toughness and strength in response to aging; and (d) subjecting said product to an aging step.
Claim 19
Independent Claim
141 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing an aluminum base alloy product containing 1.0 to 4.0 wt. % Li, 0.5 to 4.0 wt. % Cu, 0 to 3.0 wt. % Mg, 0 to 0.2 wt. % Zr, 0 to 1.0 wt. % Mn, 0.5 wt. % max. Fe, and 0.5 wt. % max Si, the balance aluminum and incidental impurities; (b) imparting to said products a working effect equivalent to stretching said product an amount greater than about 6% at room temperature; (c) selecting said alloy to be responsive to said working effect and controlling said working effect to provide improved combinations of fracture toughness and strength in response to aging; and (d) subjecting said product to an aging step.
Claim 20
Independent Claim
144 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the improved strength being obtained without substantially decreasing fracture toughness, the method comprising the steps of: (a) providing a body of a lithium containing aluminum base alloy; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product by one of stretching an amount greater than about 6% of its original length and the equivalent of stretching an amount greater than about 6% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 21
Independent Claim
144 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the improved strength being obtained without substantially decreasing fracture toughness, the method comprising the steps of: (a) providing a body of a lithium containing aluminum base alloy; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product by one of stretching an amount greater than about 6% of its original length and the equivalent of stretching an amount greater than about 6% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 22
Independent Claim
125 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body of aluminum base alloy containing at least 0.5 wt. % lithium; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product an amount equivalent to stretching the wrought product greater than about 5% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 23
Independent Claim
125 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body of aluminum base alloy containing at least 0.5 wt. % lithium; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product an amount equivalent to stretching the wrought product greater than about 5% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 24
Independent Claim
172 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body containing 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product by stretching 5 to 12% of its original length or the equivalent of stretching 5 to 12% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 25
Independent Claim
172 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body containing 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product by stretching 5 to 12% of its original length or the equivalent of stretching 5 to 12% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 26
Independent Claim
161 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body of an aluminum base alloy containing 1.0 to 4.0 wt. % Li, 0.5 to 4.0 wt. % Cu, 10 to 3.0 wt. % Mg, 0 to 0.2 wt. % Zr, 0 to 1.0 wt. % Mn, 0.5 wt. % max. Fe, and 0.5 wt. % max. Si, the balance aluminum and incidental impurities; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product by stretching about 5% to 12% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 27
Independent Claim
161 words
A method of making aluminum base alloy products having combinations of improved strength and fracture toughness in the aged condition, the method comprising the steps of: (a) providing a body of an aluminum base alloy containing 1.0 to 4.0 wt. % Li, 0.5 to 4.0 wt. % Cu, 10 to 3.0 wt. % Mg, 0 to 0.2 wt. % Zr, 0 to 1.0 wt. % Mn, 0.5 wt. % max. Fe, and 0.5 wt. % max. Si, the balance aluminum and incidental impurities; (b) working the body to produce a wrought aluminum product; (c) solution heat treating said wrought product; (d) after solution heat treating, working said wrought product by stretching about 5% to 12% of its original length; (e) selecting said alloy to be responsive to said working in step (d) and controlling said working in step (d) to provide improved combinations of strength and fracture toughness in response to aging; and (f) subjecting said product to an aging step.
Claim 28
Dependent Claim
15 words
The method according to claim 19 wherein said wrought product is stretched 6 to 12%.
Claim 29
Dependent Claim
16 words
The method according to claim 19 where in said wrought product is stretched 6 to 8%.
Claim 30
Dependent Claim
117 words
An aluminum base alloy wrought product in the aged condition having combinations of strength and fracture toughness, the product comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 1.0 to 2.0 wt. % Mn, 0 to 1.0 wt. % Zr, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities, the product having imparted thereto, prior to an aging step, a working effect equivalent to stretching an amount greater than about 5% at room temperature, said product responsive to said working effect to provide therein improved combinations of strength and fracture toughness after aging.
Claim 31
Dependent Claim
117 words
An aluminum base alloy wrought product in the aged condition having combinations of strength and fracture toughness, the product comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 1.0 to 2.0 wt. % Mn, 0 to 1.0 wt. % Zr, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities, the product having imparted thereto, prior to an aging step, a working effect equivalent to stretching an amount greater than about 5% at room temperature, said product responsive to said working effect to provide therein improved combinations of strength and fracture toughness after aging.
Claim 32
Dependent Claim
19 words
The product in accordance with claim 22 wherein Li is in the range of 1.0 to 4.0 wt. %.
Claim 33
Dependent Claim
19 words
The product in accordance with claim 22 wherein Cu is in the range of 1.0 to 5.0 wt. %.
Claim 34
Dependent Claim
64 words
The product in accordance with claim 22 wherein Li is in the range of 2.0 to 3.0 wt. %, Cu is in the range of 0.5 to 4.0 wt. %, Mg is in the range of 0 to 3.0 wt. % Zr is in the range of 0 to 0.2 wt. % and Mn is in the range of 0 to 1.0 wt. %.
Claim 35
Dependent Claim
27 words
The product in accordance with claim 22 wherein the working effect is equivalent to stretching said product an amount in the range of about 6 to 14%.
Claim 36
Dependent Claim
26 words
The product in accordance with claim 22 wherein the working effect is equivalent to stretching said product an amount in the range of 6 to 12%.
Claim 37
Dependent Claim
26 words
The product in accordance with claim 22 wherein the working effect is equivalent to stretching said product an amount in the range of 5 to 8%.
Claim 38
Dependent Claim
22 words
The product in accordance with claim 22 wherein the product is stretched an amount in the range of about 6 to 14%.
Claim 39
Dependent Claim
21 words
The product in accordance with claim 22 wherein the product is stretched an amount in the range of 5 to 12%.
Claim 40
Dependent Claim
21 words
The product in accordance with claim 22 wherein the product is rolled an amount equivalent to stretching about 6 to 14%.
Claim 41
Dependent Claim
21 words
The product in accordance with claim 22 wherein the product is forged an amount equivalent to stretching about 5 to 14%.
Claim 42
Dependent Claim
118 words
An aluminum base alloy wrought product in the aged condition having improved combinations of strength and fracture toughness, the product comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities, the product having imparted thereto, prior to said aging, a working effect equivalent to stretching an amount about 5 to 12% at room temperature, said product responsive to said working effect to provide therein an improved combinations of strength and fracture toughness after aging.
Claim 43
Dependent Claim
118 words
An aluminum base alloy wrought product in the aged condition having improved combinations of strength and fracture toughness, the product comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities, the product having imparted thereto, prior to said aging, a working effect equivalent to stretching an amount about 5 to 12% at room temperature, said product responsive to said working effect to provide therein an improved combinations of strength and fracture toughness after aging.
Claim 44
Dependent Claim
103 words
An aluminum base alloy wrought product in the aged condition having improved combinations of strength and fracture toughness, the product comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities, the product, prior to an aging step, stretched 5 to 12%, said product responsive to stretching to improved strength level without a substantial decrease in fracture toughness on aging.
Claim 45
Dependent Claim
103 words
An aluminum base alloy wrought product in the aged condition having improved combinations of strength and fracture toughness, the product comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Mg, up to 5.0 wt. % Cu, 0 to 1.0 wt. % Zr, 0 to 2.0 wt. % Mn, 0 to 7.0 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities, the product, prior to an aging step, stretched 5 to 12%, said product responsive to stretching to improved strength level without a substantial decrease in fracture toughness on aging.
Claim 46
Dependent Claim
20 words
The method according to claim 18 wherein said wrought product is stretched about 5 to 6% of its original length.
Claim 47
Dependent Claim
26 words
The method according to claim 18 wherein said wrought product is a flat rolled product and said flat rolled product is stretched about 5 to 6%.
Claim 48
Dependent Claim
15 words
The product in accordance with claim 22 wherein said product is a flat rolled product.
Claim 49
Dependent Claim
19 words
The product in accordance with claim 22 wherein the working effect equivalent to stretching is about 5 to 6%.
Claim 50
Dependent Claim
26 words
The product in accordance with claim 22 wherein the product is a sheet product and the working effect equivalent to stretching is about 5 to 6%.
Claim 51
Dependent Claim
19 words
The product in accordance with claim 33 wherein the working effect equivalent to, stretching is about 5 to 6%.
Claim 52
Dependent Claim
26 words
The product in accordance with claim 33 wherein the product is a sheet product and the working effect equivalent to stretching is about 5 to 6%.
Claim 53
Dependent Claim
19 words
The product in accordance with claim 34 wherein the working effect equivalent to stretching is about 5 to 6%.
Claim 54
Dependent Claim
24 words
The product in accordance with claim 34 wherein the product is a sheet product and the working effect equivalent to stretching is about 6%.
References Cited (Backward Citations)
US4648913A
Cited
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