Sintered polycrystalline terbium aluminum garnet and use thereof in magneto-optical devices
US7427577B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Apr 6, 2006 |
| Grant date | Sep 23, 2008 |
| Priority date | — |
| Expiry date | Oct 14, 2026 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2235/9653
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A composition is provided that includes a plurality of calcined particles of terbium aluminum oxide having a mean particle domain size of between 30 and 600 nanometers. A translucent article having a surface includes polycrystalline terbium aluminum garnet having a mean grain size from 1 to 10 microns and light scattering inclusions of aluminum-rich oxide and/or terbium-rich oxide that are present at less than 2 surface area percent of the surface. A process for forming such an article involves sintering the above provided composition at a temperature between 1500° C. and 1700° C. to yield a sintered article. The article has improved translucency and even transparency as sintering is performed under vacuum at a temperature between 1610° C. and 1680° C. Hot isostatic pressing alone or in combination with article polishing also improves article translucency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.