Aluminum nitride powder capable of forming colored sintered body and process for preparing same
US5459113A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1994 |
| Grant date | Oct 17, 1995 |
| Priority date | — |
| Expiry date | Feb 1, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/60
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A sinterable aluminum nitride powder composition is prepared by adding about 0.05-10.0 parts by weight of at least one compound selected from the group consisting of calcium tungstate and calcium molybdate and optionally about 1.0-7.0 parts by weight of at least one compound selected from the group consisting of yttria, calcium oxide, and calcium carbonate to 100 parts by weight of an aluminum nitride powder prepared by the alumina reduction method without decarbonization and having a residual carbon content of about 2%-10% by weight. The resulting powdery composition is subjected to mixing and deagglomeration in a dry process so as to form a powder mixture having a bulk density of about 0.3-0.5 g/cm.sup.3, and then to decarbonization by heating in an oxidizing atmosphere. The aluminum nitride powder composition has a pressurized bulk density of about 1.50-1.75 g/cm.sup.3 as measured at a pressure of 500 kg/cm.sup.2 and an average particle diameter of about 1.0-3.0 .mu.m in which particles having a diameter of 5 .mu.m or larger comprise not greater than about 10% by weight of the powder composition. It is capable of forming a colored sintered body with little or no unevenness of co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.