Claims
- 1. 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.degree. to 425.degree. C to obtain a non-random texture with a plastic strain ratio measured 90.degree. 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%.
- 2. A method according to claim 1 wherein said annealing step (C.) is for a period of time of at least 15 minutes.
- 3. A method as in claim 1 wherein said alloy is recrystallized by annealing at a metal temperature of from 370.degree. to 600.degree. C.
- 4. A method according to claim 3 wherein said recrystallization anneal is for a period of time of at least 15 minutes.
- 5. 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.degree. to 450.degree. C for at least 15 minutes.
- 6. 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.degree. to 600.degree. C.
- 7. A method according to claim 3 wherein said cold working step (B.) uses a reduction of at least 70%.
- 8. A method according to claim 5 wherein said annealing step (C.) is at a metal temperature of from 280.degree. to 360.degree. C.
- 9. A method according to claim 6 wherein said annealing step (C.) is at a metal temperature of from 330.degree. to 415.degree. C.
- 10. 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.
- 11. A method according to claim 3 wherein the grain structure after said annealing step (C.) is either unrecrystallized or partially recrystallized.
- 12. A method according to claim 3 wherein the annealing time in step (C.) is less than 48 hours.
- 13. A method according to claim 3 wherein the recrystallization annealing time is less than 24 hours.
Parent Case Info
This is a continuation of application Ser. No. 568,870, filed Apr. 17, 1975, now abandoned.
US Referenced Citations (4)
Continuations (1)
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Number |
Date |
Country |
Parent |
568870 |
Apr 1975 |
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