Process for producing silicon carbide heating elements
US4668452A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 1985 |
| Grant date | May 26, 1987 |
| Priority date | — |
| Expiry date | Mar 1, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/5755
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing a silicon carbide heating element is disclosed comprising: adding boron or a boron compound in an amount corresponding to from 0.3 to 3.0% by weight as boron, and carbon or a carbon compound in an amount corresponding to from 0.1 to 6.0% by weight as carbon, to a SiC powder having an average particle size of 1.0.mu. or less; blending and molding the mixture; conducting a primary sintering in vacuum or in an inert atmosphere, except nitrogen; and thereafter conducting a secondary sintering at from 1500.degree. to 2300.degree. C. in a pressurized nitrogen atmosphere to produce a silicon carbide heating element having a density of at least 80% based on the theoretical density and an electrical resistivity of 1.0 .OMEGA.-cm or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.