Non-destructive technique to pole BaTiO3 crystal
US6287486A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1999 |
| Grant date | Sep 11, 2001 |
| Priority date | — |
| Expiry date | May 28, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/36
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The structure of the barium titanate changes from cubic to tetragonal when the cooling temperature passes through the Curie temperature. This cooling process induces 90.degree. and 180.degree. domains in the crystal. The 90.degree. domains, especially, are difficult to eliminate. In the present invention of this technique, the crystal is vibrated to release and dissipate the stress in the crystal, and pressed in the a-axis direction of the crystal. The vibrating contact cumulates the strength and differs from a continual press such as in the uniaxial pressure method. Consequently, only a slight force is needed to re-orient the domains, and thus eliminate the 90.degree. domains.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.