Rapid-sintering of alumina
US4797238A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | May 12, 1987 |
| Grant date | Jan 10, 1989 |
| Priority date | — |
| Expiry date | May 12, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/91
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An improved process for producing a translucent polycrystalline alumina body comprising rapid-sintering a prefired compacted green body of alumina of predetermined shape is disclosed. The green body of alumina includes alumina doped with one or more sintering aids. Rapid sintering in accordance with the method of the present invention comprises the steps of raising the temperature of the prefired compacted green body of predetermined shape up to maximum sintering temperature at a heating rate greater than or equal to about 0.1.degree. C./second and less than the rate at which the green body experiences thermal shock; and heating the green body at the maximum sintering temperature for a period of time sufficient to produce a translucent polycrystalline alumina body. The rapid sintering is carried out under a flowing gas mixture of nitrogen and at least about 2.5 volume percent hydrogen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.