US4047978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Processing copper base alloys
Assignee: Olin Corp
•
Filing: 1976-09-29
•
Granted: 1977-09-13
•
Expires: 1996-09-29
Abstract
Abstract The instant disclosure teaches a process for obtaining an improved combination of strength and bend properties in copper base alloys having low stacking fault energy. The process is characterized by a critical combination of cold reduction and annealing following recrystallization.
Inventors
- 👤 Prakash D. Parikh
- 👤 Eugene Shapiro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:09
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/08
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
177 words
A process for obtaining an improved combination of strength and bend properties in copper base alloys having low stacking fault energy which comprises: A. providing a copper base alloy having a stacking fault energy of less than 30 ergs per square centimeter consisting essentially of a first element selected from the group consisting of about 2 to 12% aluminum, about 2 to 6% germanium, about 2 to 10% gallium, about 3 to 12% indium, about 1 to 5% silicon, about 4 to 12% tin, about 8 to 37% zinc, and the balance essentially copper wherein said alloy is fully recrystallized and has a fine grain size of less than 0.015 mm; B. cold working said alloy at least 60%; C. annealing said alloy at a metal temperature of from 280° to 425° C to obtain a non-random texture with a plastic strain ratio measured 90° to the rolling direction of less than about 0.75; wherein the grain structure after said annealing is either unrecrystallized or partially recrystallized; and D. finally cold working said material less than 40%.
Claim 2
Dependent Claim
177 words
A process for obtaining an improved combination of strength and bend properties in copper base alloys having low stacking fault energy which comprises: A. providing a copper base alloy having a stacking fault energy of less than 30 ergs per square centimeter consisting essentially of a first element selected from the group consisting of about 2 to 12% aluminum, about 2 to 6% germanium, about 2 to 10% gallium, about 3 to 12% indium, about 1 to 5% silicon, about 4 to 12% tin, about 8 to 37% zinc, and the balance essentially copper wherein said alloy is fully recrystallized and has a fine grain size of less than 0.015 mm; B. cold working said alloy at least 60%; C. annealing said alloy at a metal temperature of from 280° to 425° C to obtain a non-random texture with a plastic strain ratio measured 90° to the rolling direction of less than about 0.75; wherein the grain structure after said annealing is either unrecrystallized or partially recrystallized; and D. finally cold working said material less than 40%.
Claim 3
Dependent Claim
22 words
A method according to claim 1 wherein said annealing step (C.) is for a period of time of at least 15 minutes.
Claim 4
Dependent Claim
23 words
A method as in claim 1 wherein said alloy is recrystallized by annealing at a metal temperature of from 370° to 600° C.
Claim 5
Dependent Claim
21 words
A method according to claim 3 wherein said recrystallization anneal is for a period of time of at least 15 minutes.
Claim 6
Dependent Claim
40 words
A method according to claim 3 wherein said copper alloy contains from 25 to 35% zinc, balance essentially copper and wherein said recrystallization anneal is at a metal temperature of from 370° to 450° C for at least 15 minutes.
Claim 7
Dependent Claim
47 words
A method according to claim 3 wherein said copper alloy contains from 2 to 3% aluminum, from 1 to 3% silicon, from 0.2 to 0.5% cobalt and the balance essentially copper and wherein said recrystallization anneal is at a metal temperature of from 400° to 600° C.
Claim 8
Dependent Claim
19 words
A method according to claim 3 wherein said cold working step (B.) uses a reduction of at least 70%.
Claim 9
Dependent Claim
22 words
A method according to claim 5 wherein said annealing step (C.) is at a metal temperature of from 280° to 360° C.
Claim 10
Dependent Claim
22 words
A method according to claim 6 wherein said annealing step (C.) is at a metal temperature of from 330° to 415° C.
Claim 11
Dependent Claim
96 words
A method according to claim 1 wherein said copper base alloy contains at least one second element different from said first element selected from the group consisting of about 0.001 to 10% aluminum, about 0.001 to 4% germanium, about 0.001 to 8% gallium, about 0.001 to 10% indium, about 0.001 to 4% silicon, about 0.001 to 10% tin, about 0.001 to 37% zinc, about 0.001 to 25% nickel, about 0.001 to 0.4% phosphorus, about 0.001 to 5% iron, about 0.001 to 5% cobalt, about 0.001 to 5% zirconium, about 0.001 to 10% manganese and mixtures thereof.
Claim 12
Dependent Claim
21 words
A method according to claim 3 wherein the grain structure after said annealing step (C.) is either unrecrystallized or partially recrystallized.
Claim 13
Dependent Claim
18 words
A method according to claim 3 wherein the annealing time in step (C.) is less than 48 hours.
Claim 14
Dependent Claim
16 words
A method according to claim 3 wherein the recrystallization annealing time is less than 24 hours.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-12 | 1981-03-14 | 1981-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-12 | 1985-03-14 | 1985-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-12 | 1989-03-14 | 1989-09-13 | $7700.00 | Window Closed / Lapsed |