Sintered silicon carbide/carbon composite ceramic body having fine microstructure
US4692418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 1987 |
| Grant date | Sep 8, 1987 |
| Priority date | — |
| Expiry date | Feb 19, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/565
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Sintered silicon carbide/carbon composite ceramic body having a homogeneous very fine grain microstructure with at least 50 percent of its silicon carbide grains having a size not exceeding about 5 microns and an aspect ratio less than about 3, with graphite grains having an average size not exceeding that of the silicon carbide grains uniformly dispersed throughout the matrix of silicon carbide and having a density of at least 75 percent of theoretical can be made by firing of an infiltrated, microporous shaped green body having prior to infiltration a density of at least about 45 percent of theoretical, the shaped green body being infiltrated with an organic material which can be coked at elevated temperatures to form carbon, a sintering aid selected from the group consisting of aluminum, beryllium or boron or compounds containing any one or more of these or a mixture of any of the foregoing elements or compounds, silicon carbide having a surface area of from about 5 to about 100 square meters/gram and, optionally, a temporary binder at a sintering temperature of from about 1900.degree. C. to about 2300.degree. C. in an inert atmosphere or vacuum. The process for making such pres…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.