Patent US3754950A successfully refreshed from Google Patents.
US3754950A
Expired / Lapsed
US
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Thermal treatment of electromelted refractory materials
Assignee: Individual
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Filing: 1971-07-09
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Granted: 1973-08-28
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Expires: 1991-07-09
Abstract
Abstract A process is disclosed for imparting an increased corrosion resistance to electromelted refractory materials of the AZS type (alumina, zirconia, silica) comprising crystalline phases and one vitreous phase, the process being characterized in that the refractory material is subjected to a controlled thermal treatment at temperatures between 1300*C and 1600*C. The starting material has a chemical composition, expressed in oxides, within the following weight ranges: Al2O3 45-65%, ZrO2 10-40%, SiO2 12-20%, Na2O 0.8-1.4%, corresponding to the following weight ranges of the individual phases: Corundum 30-60%, Baddeleyite 10-40%, Mullite 0-40%, vitreous phase 15-25%.
Inventors
- 👤 G Cevales
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:44
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/653; C04B35/657; C04B35/01; C04B35/10; C04B35/107; C04B35/48; C04B35/484
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
22 words
A process as claimed in claim 1, wherein said thermal treatment is carried out at a temperature between 1,500* and 1, 600*C.
Claim 2
Dependent Claim
18 words
A process as claimed in claim 1, wherein the duration of the thermal treatment is about 10 days.
Claim 3
Dependent Claim
29 words
A process as claimed in claim 1, wherein the refractory material, after the said thermal treatment, is slowly cooled at a rate of about 120* to 150*C per day.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |