Electrically insulating ceramic sintered body
US4814581A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Oct 9, 1987 |
| Grant date | Mar 21, 1989 |
| Priority date | — |
| Expiry date | Oct 9, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23Q2007/004
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An electrically insulating ceramic sintered body suitably used in a ceramic glow plug, for example, is formed by firing a mixed powder of 75 to 95 vol % of a basic material, 25 to 5 vol % of an additive and a sintering aid. The basic material is composed of at least one material selected from the group consisting of silicon nitride, aluminum nitride, and .beta.-sialon. The additive is composed of at least one material selected from the group consisting of silicide, carbide, nitride, and boride of metal, the additive having a thermal expansion coefficient larger than that of the basic material. And the sintering aid is composed of one of alumina in an amount of 3 to 50 wt % of the total amount of the basic material and the additive, and spinel in an amount of 2 to 15 wt % of the total amount of the basic material and the additive. The sintered body has the structure that particles of the additive cohere and the cohering additive particles are dispersed in particles of the basic material so as to be surrounded by the particles of the basic material and separated from adjacent cohering additive particles by the particles of the basic material. When the sintered body is used as a heate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.