Patent US3753744A successfully refreshed from Google Patents.
US3753744A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Graphite-alumina-silicon carbide base refractory
Assignee: Nippon Crucible Co Ltd
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Filing: 1971-12-27
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Granted: 1973-08-21
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Expires: 1991-12-27
Abstract
Abstract This invention provides a graphite-alumina-silicon carbide base refractory having good erosion resistance, spalling resistance and durable for oxidizing attack at elevated temperature. This refractory contains more than 85 wt. percent of main components of graphite (including combined carbon), alumina and silicon carbide (the weight ratio of graphite:alumina:silicon carbide being 10-38:60-80:2-18), and these three main components are combined with each other by a carbon bond which contains glassy material (2-6 wt. percent) and forms the network structure.
Inventors
- 👤 I Komaru
- 👤 K Takeda
- 👤 K Yuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:57
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
22 words
The refractory of claim 1, wherein said alumina is an electrofused or sintered alumina having a purity of at least 94 percent.
Claim 2
Dependent Claim
20 words
The refractory of claim 1, wherein said graphite is a naturally occurring graphite in a flake, vein or amorphous form.
Claim 3
Dependent Claim
25 words
The refractory of claim 1, wherein said carbon binder contains 1 to 7 percent by weight of silicon or its alloy in the pulverized state.
Claim 4
Dependent Claim
24 words
The refractory of claim 1, wherein said vitreous matter has a softening point of 800* to 1,200* C and has good wettability with graphite.
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) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |