Silicon nitride sintered bodies of Si.sub.3 N.sub.4, Y.sub.2 O.sub.3, MgO and ZrO.sub.2
US4560669A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1983 |
| Grant date | Dec 24, 1985 |
| Priority date | — |
| Expiry date | Oct 11, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/584
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Highly densified silicon nitride sintered bodies having excellent mechanical strength and oxidation resistance consist essentially of Si.sub.3 N.sub.4 and contain Y, Mg and Zr, in which a content of Si.sub.3 N.sub.4 is 95-70% by weight, a content of yttrium is 15-2% by weight calculated as Y.sub.2 O.sub.3, a content of magnesium is 15-0.5% by weight calculated as MgO and a content of zirconium is 13-0.5% by weight calculated as ZrO.sub.2 and are produced by forming a mixed raw powder consisting of 95-70% by weight of silicon nitride raw powder, yttrium compound of 15-2% by weight calculated as Y.sub.2 O.sub.3, magnesium compound of 15-0.5% by weight calculated as MgO and zirconium compound of 13-0.5% by weight calculated as ZrO.sub.2 into a shaped body, said yttrium compound, magnesium compound and zirconium compound being sintering aids, and firing the shaped body at a temperature of 1,650.degree.-1,800.degree. C. under ambient pressure in a nitrogen or an inert gas atmosphere.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.