Rapid sintering method for producing alumina-titanium carbide composites
US5342564A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1992 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Dec 31, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/117
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of making a sintered ceramic body for applications such as wear resistant parts and cutting tools. A green body is prepared from a powder mixture including alumina, TiC or (Ti(C,N)), a densification aid, and TiO.sub.2. The weight ratio of alumina to TiC in the body is about 40:60 to about 95:5; that of TiO.sub.2 to alumina plus TiC is 0:100 to about 2:98. The green body is rapid sintered by heating in a sintering atmosphere to about 1800.degree.-1920.degree. C. for a time sufficient to achieve a density of at least about 4.20 g/cc. The heating rate above about 800.degree. C. is between about 120.degree. C./min and the rate at which the green body experiences thermal shock. The sintering atmosphere is Ar-H.sub.2 or N.sub.2 -H.sub.2 in a molar ratio of Ar or N.sub.2 to H.sub.2 of about 92:8 to 100:0. Carbon monoxide is introduced to the sintering atmosphere only after the sintering temperature exceeds about 1400.degree. C. The amount of CO introduced is selected to inhibit reaction between the alumina and TiC. The CO may be introduced by placing a mass of graphite including adsorbed oxygen and water in the furnace at initiation of sintering such that the mass releases CO onl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.