Electrically-conductive sintered compact of silicon nitride machinable by electrical discharge machining and process of producing the same
US4659508A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 1985 |
| Grant date | Apr 21, 1987 |
| Priority date | — |
| Expiry date | Nov 4, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/593
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An electrically-conductive sintered compact of silicon nitride which is machinable by electrical discharge machining and a process to produce the same. TiN and/or TiC powder is added to a powder of silicon nitride in an amount 15-40% by volume to act as a conductivity-supplying agent while 0.01-3.0% by volume MgO and/or Al.sub.2 O.sub.3 powder is added as a sintering assistant. The mixed powders are then preformed in a desired shape and sintered in a nonoxidizing environment at 1,600.degree. C.-2,000.degree. C. to obtain a compact of silicon-nitride machinable by electrical discharge machining due to its electrical conductivity being at least 1 S.multidot.cm.sup.-1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.