Transparent yttria ceramics and method for producing same
US4147744A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 31, 1978 |
| Grant date | Apr 3, 1979 |
| Priority date | — |
| Expiry date | Mar 31, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/505
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An article of manufacture is provided comprising a substantially transparent high density polycrystalline yttria-base body consisting essentially of yttria and from about 6 to 14 mole percent lanthana. A method for preparing the transparent yttria doped with lanthana is also provided comprising admixing or co-precipitating lanthana or a precursor thereof with yttria or a precursor thereof, washing, drying and screening the mixture, calcining the admixed or co-precipitated powders, pressing the calcined powders into a desired shape and thereafter sintering the shaped powder for from about 1/6 to 6 hours at a temperature above the H-phase transition and for from about 1/2 to 6 hours at a temperature below the H to C phase transition, said sintering being effected at a sufficiently low oxygen atmosphere to prevent oxidative contaminants.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.