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US4629707A
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High strength, low mass porous silicon nitride based articles
Assignee: Osram Sylvania Inc
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Filing: 1986-01-21
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Granted: 1986-12-16
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Expires: 2006-01-21
Abstract
Abstract An article is disclosed which is made of silicon nitride based material consisting essentially of in percent by weight about 6% yttrium oxide and the balance silicon nitride. The article has open porosity of from about 37% by volume at which level the strength of the article is about 15 ksi to about 10% by volume open porosity at which level the strength of the article is about 72 ksi. The article can have within its open porosity a lubricating material.
Inventors
- 👤 Robert W. Wolfe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:13
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B38/00; C04B41/45; C04B41/46; C04B41/47; C04B41/478; C04B41/50; C04B41/5053; C04B41/80; C04B41/81; C04B41/82; C04B41/85; C04B41/87; F; F16; F16C; F16C33/00; F16C33/02; F16C33/04; F16C33/043; F16J; F16J1/00; F16J1/08; F16J1/10; F16J1/14; F16J1/16
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
75 words
An article made of silicon nitride based material, said material consisting essentially of in percent by weight about 6% yttrium oxide, and the balance silicon nitride, said article having an open porosity of from about 37% by volume at which level of porosity the strength of said article is about 15 ksi, to an open porosity of about 10% by volume at which level of porosity the strength of said article is about 72 ksi.
Claim 2
Dependent Claim
75 words
An article made of silicon nitride based material, said material consisting essentially of in percent by weight about 6% yttrium oxide, and the balance silicon nitride, said article having an open porosity of from about 37% by volume at which level of porosity the strength of said article is about 15 ksi, to an open porosity of about 10% by volume at which level of porosity the strength of said article is about 72 ksi.
Claim 3
Dependent Claim
87 words
An article made of silicon nitride based material, said material consisting essentially of in percent by weight about 6% yttrium oxide, and the balance silicon nitride, said article having an open porosity of from about 37% by volume at which level of porosity the strength of said article is about 15 ksi, to an open porosity of about 10% by volume at which level of porosity the strength of said article is at least about 72 ksi, said article having within its open porosity a lubricating material.
Claim 4
Dependent Claim
87 words
An article made of silicon nitride based material, said material consisting essentially of in percent by weight about 6% yttrium oxide, and the balance silicon nitride, said article having an open porosity of from about 37% by volume at which level of porosity the strength of said article is about 15 ksi, to an open porosity of about 10% by volume at which level of porosity the strength of said article is at least about 72 ksi, said article having within its open porosity a lubricating material.
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) | 1989-12-15 | 1990-06-16 | 1990-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-15 | 1994-06-16 | 1994-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-15 | 1998-06-16 | 1998-12-16 | $7700.00 | Window Closed / Lapsed |