Continuous process for producing alumina-titanium carbide compos

Details Continuous process for producing alumina-titanium carbide compos Continuous process for producing alumina-titanium carbide compos

1992-12-31

1995-02-21

Derrington, James

Plastic and nonmetallic article shaping or treating: processes

Including step of generating heat by friction

264 57, 264 63, 264 66, C04B 3510, C04B 3564

Patent

active

053913396

ABSTRACT:
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 TiO.sub.2 in a weight ratio of TiO.sub.2 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 N.sub.2 containing up to 8 w/o H.sub.2 to about 1800.degree.-1920.degree. 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.degree. C. between about 225.degree. 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.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 in the furnace such that CO is released only above 1400.degree. 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.

REFERENCES:
patent: 4063908 (1977-12-01), Ogawa et al.
patent: 4490319 (1984-12-01), Lee et al.
patent: 4762655 (1988-08-01), Rhodes et al.
patent: 4792353 (1988-12-01), Kramer et al.
patent: 4797238 (1989-01-01), Rhodes et al.
patent: 4948538 (1990-08-01), Wei et al.
Rapid Rate Sintering of Al.sub.2 O.sub.3 --TiC Composites for Cutting--Tool Application--Lee, et al., In Advanced Ceramics Materials, 38-44 (1988).
Fast Firing of Alumina Ceramics--Harmer, et al., Materials Science Mongraph, 6, Energy & Ceramics, 1980 Elsevier Pub. Corp.
Pressureless sintering of TiC-Al.sub.2 O.sub.3 composites, Ishigaki, et al., In Journal of Materials Sci & Letters, 1989, pp. 678-680.
Pressureless Sintering of Alumina--Titanium Carbide Composites--Kim et al., In J. Am. Ceramic Sci., 72, 8, 1333-1337 (1989).
Fracture Toughness of the Systems Al.sub.2 O.sub.3 --TiC Ceramic--Furukawa, In Nippon Tungsten Review, vol. 18, 1985, pp. 16-22.
Fracture behavior of composites based on Al.sub.2 O.sub.3 --TiC, Wahl, et al., In Journal of Materials Science, 1980, pp. 875-880.
Pressureless--sintered Al.sub.2 O.sub.3 --TiC Composites, Cutler, et al., In Materials Science & Eng., A105/106, 1988, pp. 183-192.

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