Method for preparing dense, .beta.-alumina ceramic bodies
US4013477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1975 |
| Grant date | Mar 22, 1977 |
| Priority date | — |
| Expiry date | Jul 30, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for preparing a dense and strong polycrystalline .beta."-alumina-containing ceramic body exhibiting an elecrical resistivity at 300.degree. C of 5 ohm-cm or lower, and a controlled and uniform grain size under 50 micrometers, comprising: PA1 A. preparing fully converted .beta."-alumina seeds; PA1 B. mechanically mixing in the above-mentioned .beta."-alumina seeds with a matrix powder of a composition consistent with the formation of .beta."-alumina upon sintering; and PA1 C. sintering at about 1600.degree. C for less than 10 minutes in an open-air atmosphere or under noble metal encapsulation, a green ceramic body formed from the powder mixture of which one ingredient is the .beta."-alumina seeds and the other ingredient is the matrix powder of a composition consistent with the formation of .beta."-alumina. The polycrystalline .beta."-alumina-containing ceramic bodies obtained by the method of this invention exhibit high density, low porosity, high strength, fine grain size, and low electrical resistivity. Such polycrystalline .beta."-alumina-containing bodies are ideally suited for use as solid reaction zone separator or solid elecrolyte in certain electrical conversion d…
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