Patent US4069059A successfully refreshed from Google Patents.
US4069059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicon nitride-zirconium silicate ceramics
Assignee: United States Department of the Navy
•
Filing: 1976-06-11
•
Granted: 1978-01-17
•
Expires: 1996-06-11
Abstract
Abstract A dense and high temperature-oxidation-resistant ceramic prepared from silicon nitride and zirconium silicate in an amount from 3 to 15 weight percent of silicon nitride.
Inventors
- 👤 William J. McDonough
- 👤 Roy W. Rice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:44
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/593
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
30 words
A dense and high-temperature-oxidation-resistant ceramic prepared from a mixture consisting of silicon nitride and of zirconium silicate in an amount from 3 to 15 weight percent of said silicon nitride.
Claim 2
Dependent Claim
30 words
A dense and high-temperature-oxidation-resistant ceramic prepared from a mixture consisting of silicon nitride and of zirconium silicate in an amount from 3 to 15 weight percent of said silicon nitride.
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) | 1981-01-16 | 1981-07-18 | 1982-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-16 | 1985-07-18 | 1986-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-16 | 1989-07-18 | 1990-01-17 | $7700.00 | Window Closed / Lapsed |