"Alkali-metal-.beta.- and .beta.""-alumina and gallate polycrystalline ceramics and fabrication by a vapor phase method"
US6117807A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 2, 1998 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Jan 2, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ceramic composite containing alkali-metal-.beta.- or .beta."-alumina and an oxygen-ion conductor is fabricated by converting .alpha.-alumina to alkali-metal-.beta.- or .beta."-alumina. A ceramic composite with continuous phases of .alpha.-alumina and the oxygen-ion conducting ceramic, such as zirconia, is exposed to a vapor containing an alkali-metal oxide, such as an oxide of sodium or potassium. Alkali metal ions diffuse through alkali-metal-.beta.- or .beta."-alumina converted from .alpha.-alumina and oxygen ions diffuse through the oxygen-ion conducting ceramic to a reaction front where .alpha.-alumina is converted to alkali-metal-.beta.- or .beta."-alumina. A stabilizer for alkali-metal-.beta."-alumina is preferably introduced into the .alpha.-alumina/oxygen-ion conductor composite or introduced into the vapor used to convert the .alpha.-alumina to an alkali-metal-.beta."-alumina.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.