Gas pressure sintered silicon nitride having high strength and stress rupture resistance
US5759933A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1997 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Jan 27, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B41/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A silicon nitride sintered body has a composition consisting essentially of 80 to 93% by weight .beta. silicon nitride, 7 to 20% by weight grain boundary phases consisting essentially of (i) at least two rare earth elements, wherein yttrium is considered a rare earth, and strontium which, calculated as SrO, is 0.5 to 5% by weight, and (ii) at least two of Si, N, O and C; and (c) silicon carbide particulate present in the amount of about 5 to 35 parts by weight per 100 parts by weight of components (a) and (b), said SiC being substantially homogeneously dispersed within said sintered body. Such a ceramic has high strength and long term durability, and is especially suited for industrial applications such as components for gas turbine and automotive engines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.