Patent US4233069A successfully refreshed from Google Patents.
US4233069A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Modified brass alloys with improved stress relaxation resistance
Assignee: Olin Corp
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Filing: 1979-11-05
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Granted: 1980-11-11
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Expires: 1999-11-05
Abstract
Abstract An alloy system which exhibits improved resistance to stress relaxation at elevated temperatures utilizes additions of magnesium plus aluminum to a copper-zinc base to attain the stress relaxation performance. Processing of this alloy system should be performed so as to maintain at least 90% by weight alpha-phase within the alloy.
Inventors
- 👤 Warren F. Smith, Jr.
- 👤 John M. Vitek
- 👤 Eugene Shapiro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:20
CPC Classifications
C; C22; C22C; C22C9/00; C22C9/04; C22F; C22F1/00; C22F1/08
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
49 words
An essentially single-phase alpha alloy which is particularly resistant to stress relaxation at elevated temperatures, said alloy consisting essentially of from 0.05 to 0.5% by weight magnesium, from 0.02 to 0.5% by weight aluminum, from 8 to 32.8% by weight zinc, balance copper, with the maximum wt.% zinc=32.8-4.8×wt.% aluminum.
Claim 2
Dependent Claim
49 words
An essentially single-phase alpha alloy which is particularly resistant to stress relaxation at elevated temperatures, said alloy consisting essentially of from 0.05 to 0.5% by weight magnesium, from 0.02 to 0.5% by weight aluminum, from 8 to 32.8% by weight zinc, balance copper, with the maximum wt.% zinc=32.8-4.8×wt.% aluminum.
Claim 3
Dependent Claim
26 words
An alloy according to claim 1 wherein said magnesium is from 0.1 to 0.5% by weight and said aluminum is from 0.05 to 0.5% by weight.
Claim 4
Dependent Claim
21 words
An alloy according to claim 2 wherein the amount of said magnesium in the alloy is 0.1 to 0.2% by weight.
Claim 5
Dependent Claim
22 words
An alloy according to claim 1 wherein said alpha-phase within the alloy accounts for at least 90% by weight of the alloy.
Claim 6
Dependent Claim
25 words
An alloy according to claim 1 wherein said alloy is in the worked condition and has a grain size of approximately 0.005 to 0.050 mm.
Claim 7
Dependent Claim
23 words
An alloy according to claim 1 which is essentially a single-phase alpha alloy at elevated temperatures approaching the solidus temperature of said alloy.
Claim 8
Independent Claim
124 words
A method for producing an essentially single-phase alpha alloy which is particularly resistant to stress relaxation at elevated temperatures, said method comprising the steps of: (a) casting an alloy consisting essentially of from 0.05 to 0.5% by weight magnesium, from 0.02 to 0.5% by weight aluminum, from 8 to 32.8% by weight zinc, balance copper, with the maximum wt.% zinc=32.8-4.8×wt.% aluminum; (b) hot working said alloy at a temperature above the recrystallization temperature of the alloy and below the solidus temperature of the alloy; (c) cold working said alloy with up to but not including a 100% reduction in area; and (d) annealing the worked alloy at 150° to 900° C. to recrystallize the alloy to a grain size of 0.005 to 0.050 mm.
Claim 9
Independent Claim
124 words
A method for producing an essentially single-phase alpha alloy which is particularly resistant to stress relaxation at elevated temperatures, said method comprising the steps of: (a) casting an alloy consisting essentially of from 0.05 to 0.5% by weight magnesium, from 0.02 to 0.5% by weight aluminum, from 8 to 32.8% by weight zinc, balance copper, with the maximum wt.% zinc=32.8-4.8×wt.% aluminum; (b) hot working said alloy at a temperature above the recrystallization temperature of the alloy and below the solidus temperature of the alloy; (c) cold working said alloy with up to but not including a 100% reduction in area; and (d) annealing the worked alloy at 150° to 900° C. to recrystallize the alloy to a grain size of 0.005 to 0.050 mm.
Claim 10
Dependent Claim
30 words
A method according to claim 7 wherein said cold working is accomplished in cycles with said annealing provided that a cold working step is the last step of the cycle.
Claim 11
Dependent Claim
27 words
A method according to claim 7 wherein said beta-phase in the alloy is kept to a maximum of 10% by weight throughout the processing of the alloy.
Claim 12
Dependent Claim
30 words
A method according to claim 7 wherein said alloy is annealed at 200° to 800° C. for 1 to 24 hours after said hot working but before said cold working.
Claim 13
Dependent Claim
16 words
A method according to claim 7 wherein said hot working is at 500° to 1000° C.
Claim 14
Dependent Claim
22 words
A method according to claim 7 wherein said cold working utilizes a 10 to 98% reduction in cross-sectional area of said alloy.
Claim 15
Dependent Claim
25 words
A method according to claim 7 wherein the surface of said alloy is milled or cleaned after said hot working but before said cold working.
Claim 16
Dependent Claim
27 words
A method according to claim 7 wherein said magnesium is from 0.1 to 0.5% by weight and said aluminum is from 0.1 to 0.5% by weight aluminum.
Claim 17
Dependent Claim
22 words
An alloy according to claim 14 wherein the amount of said magnesium in the alloy is from 0.1 to 0.2% by weight.
References Cited (Backward Citations)
US1938172A
Cited
GB575316A
Cited
US2935400A
Cited
US3253910A
Cited
US3982933A
Cited
JPS512414A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-11 | 1984-05-12 | 1984-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-11 | 1988-05-12 | 1988-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-11 | 1992-05-12 | 1992-11-11 | $7700.00 | Window Closed / Lapsed |