| 摘要 |
A method of making a continuously sintered ceramic body. A ceramic green body is prepared from a powder mixture comprising alumina, TiC (or Ti(C,N)), in a weight ratio of alumina to TiC of about 40:60-95:5, a densification aid, and TiO2 in a weight ratio of TiO2 to alumina plus TiC of 0:100 to about 2:98. The green body is prefired, then continuously rapid sintered by heating in a belt furnace in Ar or N2 containing up to 8 w/o H2 to about 1800 DEG -1920 DEG C. for a time sufficient to achieve a density of at least about 4.12 g/cc. The rate of travel of the prefired body through the belt furnace provides a heating rate above about 800 DEG C. between about 225 DEG C./min. and the rate at which the body experiences thermal shock. Carbon monoxide is intoduced to the atmosphere during the sintering step only after the temperature exceeds about 1400 DEG 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 in the furnace such that CO is released only above 1400 DEG C. The body may be prepared from a homogeneous slurry, and the green body may be presintered, isopressed, and sintered or sintered and hot-isostatic-pressed.
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