Claims
- 1. A process for forming a composite having improved resistance to stress relaxation at temperatures of at least about 150.degree. C., said process comprising:
- bonding a substrate material comprising a copper base alloy consisting essentially of from about 0.05% to about 0.5% by weight zirconium and the balance essentially copper to at least one layer of a copper-nickel alloy clad material containing more than about 30% nickel;
- heating said bonded substrate and clad material to a temperature from about 600.degree. C. to about 980.degree. C. for a time period from about 2 minutes to about 24 hours; and
- increasing the electrical conductivity of said substrate material by cooling said bonded materials to a temperature in the range of from about 475.degree. C. to about 725.degree. C. for at least about 30 minutes.
- 2. The process of claim 1 wherein:
- said heating step comprises heating said bonded materials to a temperature from about 700.degree. C. to about 800.degree. C. for a time in the range of from about 30 minutes to about 4 hours; and
- said electrical conductivity increasing step comprises cooling said bonded materials to a temperature in the range of from about 550.degree. C. to about 650.degree. C. for a time period in the range of from about 2 hours to about 4 hours.
- 3. The process of claim 1 further comprising:
- cold working said bonded materials after said electrical conductivity increasing step.
- 4. The process of claim 1 wherein said bonding step comprises:
- rolling said substrate and clad materials together in a single pass with a reduction from about 50% to about 75% to produce a composite with a substrate and at least one clad layer having a thickness of at least about 10% of the overall thickness of said composite.
- 5. The process of claim 4 wherein said rolling step produces a composite having said substrate and at least one clad layer having a thickness of at least about 20% of the overall thickness of said composite.
- 6. The process of claim 4 wherein said bonding step comprises:
- bonding the substrate material to two layers of the copper-nickel alloy clad material thereby forming a three layer composite.
- 7. The process of claim 1 wherein said bonding step comprises:
- bonding a substrate material comprising a copper base alloy consisting essentially of from about 0.05% to about 0.15% by weight zirconium and the balance essentially copper to at least one layer of a copper-nickel alloy clad material containing more than about 30% by weight nickel.
Parent Case Info
This application is a division of U.S. patent application Ser. No. 866,665, filed May 27, 1986 now U.S. Pat. No. 4,735,868.
US Referenced Citations (14)
Foreign Referenced Citations (4)
Number |
Date |
Country |
1165876 |
Mar 1964 |
DEX |
88996 |
Aug 1978 |
JPX |
104597 |
Aug 1979 |
JPX |
87857 |
May 1986 |
JPX |
Non-Patent Literature Citations (2)
Entry |
"Electrical Manufacturing", Aug. 1956, pp. 117-121. |
"Metallic Materials Specification Handbook", Robert B. Ross, Third Edition, pp. 247-250, Editor E. & F. N. Spon, GB; 27D Nickel-Copper Wrought and Cast Alloys. |
Divisions (1)
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Number |
Date |
Country |
Parent |
866665 |
May 1986 |
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