Patent US3215547A successfully refreshed from Google Patents.
US3215547A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat resisting material and method for making it
Assignee: National Research Development Corp UK
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Filing: 1962-09-20
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Granted: 1965-11-02
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Expires: 1982-09-20
Abstract
No abstract record available.
Inventors
- 👤 Parr Norman Lawrence
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:55
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/591
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
A METHOD OF MAKING A SHAPED BODY DESIGNED TO WITHSTAND HIGH TEMPERATURE AND TO RESIST CREEP AND THERMAL SHOCK AT SUCH TEMPERATURE COMPRISING THE STEPS OF COMPACTING POWDERED SILCON AND UP TO 10% BY WEIGHT FINELY DIVIDED SILICON CARBIDE EVENLY DISTRIBUTED IN THE SILICON INTO THE REQUIRED SHAPE, FIRING THE MIXTURE IN AN ATMOSPHERE OF NITROGEN INITIALLY AT A TEMPERATURE BELOW THE MELTING POINT OF SILICON FOR SUFFICIENT TIME TO PRODUCE A RIGID NETWORK OF SILICON NITRIDE RETAINING THE REMAINING UNCOMBINED SILICON, FIRING IN NITROGEN AT A TEMPERATURE ABOVE THE MELTING POINT OF SILICON TOEFFECT PARTIAL NITRIDING OF THE REMAINING UNCOMBINED SILICON, AND THEN FIRING IN AN OXIDIZING ATMOSPHERE TO CONVERTTHE UNREACTED SILICON AT LEAST PARTIALLY TO SILICON DIOXIDE.
Claim 2
Independent Claim
119 words
A METHOD OF MAKING A SHAPED BODY DESIGNED TO WITHSTAND HIGH TEMPERATURE AND TO RESIST CREEP AND THERMAL SHOCK AT SUCH TEMPERATURE COMPRISING THE STEPS OF COMPACTING POWDERED SILCON AND UP TO 10% BY WEIGHT FINELY DIVIDED SILICON CARBIDE EVENLY DISTRIBUTED IN THE SILICON INTO THE REQUIRED SHAPE, FIRING THE MIXTURE IN AN ATMOSPHERE OF NITROGEN INITIALLY AT A TEMPERATURE BELOW THE MELTING POINT OF SILICON FOR SUFFICIENT TIME TO PRODUCE A RIGID NETWORK OF SILICON NITRIDE RETAINING THE REMAINING UNCOMBINED SILICON, FIRING IN NITROGEN AT A TEMPERATURE ABOVE THE MELTING POINT OF SILICON TOEFFECT PARTIAL NITRIDING OF THE REMAINING UNCOMBINED SILICON, AND THEN FIRING IN AN OXIDIZING ATMOSPHERE TO CONVERTTHE UNREACTED SILICON AT LEAST PARTIALLY TO SILICON DIOXIDE.
References Cited (Backward Citations)
US2750268A
Cited
US2968530A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-01 | 1969-05-03 | 1969-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-01 | 1973-05-03 | 1973-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-01 | 1977-05-03 | 1977-11-02 | $7700.00 | Window Closed / Lapsed |