Fiber-reinforced silicon nitride composite ceramics
US4885199A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1986 |
| Grant date | Dec 5, 1989 |
| Priority date | — |
| Expiry date | Nov 26, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/265
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Tough composites of polymer derived silicon carbide fibers in silicon nitride matrices, especially reaction bonded silicon nitride matrices, can be made by precoating the fibers with pyrolytic carbon and controlling the nitridation or other process which forms the silicon nitride matrix so that a thickness of at least 5 nanometers of carbon remains in the composite after it is formed. Failure of such composites is non-catastrophic. Alternatively, with at least some specific types of polymer derived silicon carbide fibers, composites with non-catastrophic failure can be made by controlling the nitriding conditions to produce an essentially void space around the fibers in the final composites. As still another alternative, the space around the fibers may be partially filled with silicon nitride whiskers generated during the nitridation process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.