US3765866A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of copper and copper oxide powder for powder metallurgy
Assignee: Contemporary Research Inc
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Filing: 1971-10-08
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Granted: 1973-10-16
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Expires: 1991-10-08
Abstract
Abstract Copper base (including pure copper and copper alloy) or copper oxide powder is produced by atomizing a sulfurized copper base melt in the presence of oxygen to produce particles which are hollow as a result of sulfur dioxide formation therewithin, oxidizing the hollow particles in the presence of oxygen in order to cause weakening at the grain boundaries as a result of more sulfur dioxide formation therein, and crushing in order to make available the copper base particles. If desired, the oxidizing step, when carried for a longer time, results in oxidation of copper as well as sulfur and the crushing step results in copper oxide particles.
Inventors
- 👤 H Nayar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:03
CPC Classifications
C; C01; C01G; C01G3/00; C01G3/02; B; B22; B22F; B22F9/00; C01P; C01P2004/00; C01P2004/20; C01P2004/30; C01P2004/32; C01P2004/34; C01P2004/60; C01P2004/61; C01P2006/00; C01P2006/32; C01P2006/33; C01P2006/34; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12479; Y10T428/29; Y10T428/2982; Y10T428/2991
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
27 words
The mass of low apparent density copper base particles of claim 1 wherein the wall thickness of said hollow shell characteristically is less than 250 microns thick.
References Cited (Backward Citations)
US2870485A
Cited
US3293006A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |