Neodymium titanate and barium neodymium titanate, processes for their preparation, and their applications in ceramic compositions
US4757037A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 3, 1986 |
| Grant date | Jul 12, 1988 |
| Priority date | — |
| Expiry date | Mar 3, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/61
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A fine powder of neodymium titanate or barium neodymium titanate, a process for its preparation and applications in ceramic compositions. A suspension of particles is formed by mixing a solution of neodymium nitrate or a solution of barium and neodymium nitrates with a sol of titania having a pH of from about 0.8 to 2.5 which contains elementary crystallites of TiO.sub.2 having a size of from about 10 to about 100 .ANG. in diameter which are agglomerated into submicron masses of from about 200 to about 1,000 .ANG. in diameter. The suspension obtained is dried, and the dried product is calcined at a temperature between 800.degree. C. and 1,300.degree. C., preferably for about 1 to 24 hours. If necessary, the powder obtained is milled. The fine powder obtained has a low fritting temperature and its density after heating for 2 hours at 1,300.degree. C. is greater than or equal to 95% of the theoretical density of the desired titanate powder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.