Grain oriented ceramics, thermoelectric conversion element and production process thereof
US6806218B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2002 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Apr 26, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2235/94
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Grain oriented ceramics constituted of a polycrystalline body of a layered cobaltite in which a {001} plane of each grain constituting the polycrystalline body has an average orientation degree of 50% or more by the Lotgering's method. In this case, the layered cobaltite is preferably a layered calcium cobaltite expressed by the following general formula:{(Ca1−xAx)2CoO3+&agr;} (CoO2+&bgr;)y (where A represents one or more elements selected among an alkali metal, an alkaline earth metal and Bi, 0≦×≦0.3, 0.5≦y≦2.0, and 0.85≦{3+&agr;+(2+&bgr;)y}/(3+2y)≦1.15). Such grain oriented ceramics are obtained by molding a mixture of the first powder constituted of a Co(OH)2 platelike powder and the second powder constituted of CaCO3 and the like such that a developed plane of the platelike powder is oriented, and by heating the green body at a predetermined temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.