US3287478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of sintering aluminum nitride refractories
Assignee: Allis Chalmers Corp
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Filing: 1964-10-30
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Granted: 1966-11-22
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Expires: 1984-10-30
Abstract
No abstract record available.
Inventors
- 👤 Michael S Pallen
- 👤 George T Poglud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:06
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
124 words
THE METHOD OF PRODUCING REFRACTORY BODIES COMPRISING THE STEPS OF: (A) PRODUCING A PRESSED FORM OF THE REFRACTORY BODY DESIRED FROM POWDERS SELECTED FROM THE GROUP OF CONSISTING OF ALUMINUM NITRIDE AND SOLID SOLUTION OF ALUMINUM NITRIDE-SILICON CARBIDE AND CONTAINING FROM 2.5 TO 20 WEIGHT PERCENT WATER; (B) HEATING SAID BODY SLOWLY IN AN INERT ATMOSPHERE, UNTIL THE WATER HAS BEEN DRIVEN FROM SAID BODY; (C) FURTHER HEATING SAID BODY IN INERT ATMOSPHERE TO A FINAL TEMPERATURE IN THE RANGE OF FROM ABOUT 1600 TO 2200* C; (D) MAINTAINING SAID FINAL TEMPERATURE FOR A PERIOD OF FROM FIVE MINUTES TO TWO HOURS; (E) COOLING SAID BODY; AND (F) REMOVING A THIN LAYER OF POWDER WHICH REMAINS ON THE SURFACES OF THE BODY AFTER SINTERING.
Claim 2
Independent Claim
124 words
THE METHOD OF PRODUCING REFRACTORY BODIES COMPRISING THE STEPS OF: (A) PRODUCING A PRESSED FORM OF THE REFRACTORY BODY DESIRED FROM POWDERS SELECTED FROM THE GROUP OF CONSISTING OF ALUMINUM NITRIDE AND SOLID SOLUTION OF ALUMINUM NITRIDE-SILICON CARBIDE AND CONTAINING FROM 2.5 TO 20 WEIGHT PERCENT WATER; (B) HEATING SAID BODY SLOWLY IN AN INERT ATMOSPHERE, UNTIL THE WATER HAS BEEN DRIVEN FROM SAID BODY; (C) FURTHER HEATING SAID BODY IN INERT ATMOSPHERE TO A FINAL TEMPERATURE IN THE RANGE OF FROM ABOUT 1600 TO 2200* C; (D) MAINTAINING SAID FINAL TEMPERATURE FOR A PERIOD OF FROM FIVE MINUTES TO TWO HOURS; (E) COOLING SAID BODY; AND (F) REMOVING A THIN LAYER OF POWDER WHICH REMAINS ON THE SURFACES OF THE BODY AFTER SINTERING.
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) | 1969-11-21 | 1970-05-23 | 1970-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-11-21 | 1974-05-23 | 1974-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-11-21 | 1978-05-23 | 1978-11-22 | $7700.00 | Window Closed / Lapsed |