Claims
- 1. A method for producing a self-supporting ceramic composite body by oxidation of a parent metal, said ceramic composite body having a microstructure characterized by at least two zones which differ from each other in at least one property, which method comprises the steps of: (a) orienting at least one first filler material adjacent to said parent metal, (b) heating said parent metal in the presence of a first oxidant to form a body of molten metal and reacting said molten metal with said oxidant at a suitable temperature to form an oxidation reaction product, which product is in contact with and extends between said body of molten metal and said first oxidant, (c) at said temperature, transporting said molten metal through said oxidation reaction product towards said first oxidant so that oxidation reaction product continues to form at the interface between said first oxidant and previously formed oxidation reaction product thereby forming a progressively thicker body of said oxidation reaction product which embeds at least a portion of said at least one first filler material, (d) providing at least one second filler material which is different from said at least one filler material during formation of said ceramic composite body such that said providing of said at least one second filler material is sufficient to form at least two different zones of oxidation reaction product which differ from each other in at least one property, (e) continuing said reaction for a time sufficient to produce said ceramic composite body, and (f) recovering the resulting ceramic composite body.
- 2. The method of claim 1, wherein at least one zone of said at least two different zones differs from the remainder of said at least two different zones in at least one property selected from the group consisting of mechanical strength and thermal expansion.
- 3. A self-supporting ceramic composite body comprising at least two different zones, each of said at least two different zones comprising oxidation reaction product and said at least two zones being in intimate juxtaposition, wherein said oxidation reaction product in each of said at least two different zones comprises an interconnected polycrystalline ceramic matrix, at least one filler embedded within said ceramic matrix and an interconnected metallic component, said oxidation reaction product being substantially similar in composition in each of said at least two different zones, and wherein at least one of said at least two zones comprises at least one filler which is different from the at least one filler in a remainder of said at least two different zones, said difference being evidenced by at least one of composition, size and gradient of said at least one filler throughout the zone.
- 4. The self-supporting ceramic composite body of claim 3, wherein said at least one filler material comprises a preform of said at least one filler.
- 5. The self-supporting ceramic composite body of claim 3, wherein at least one zone of said at least two different zones differs from the remainder of said at least two different zones in at least one property selected from the group consisting of mechanical strength and thermal expansion.
- 6. The self-supporting ceramic composite body of claim 3, wherein said difference of said at least one filler in said at least one of said at least two zones comprises at least one of a composition gradient and a size gradient throughout said at least one zone.
Parent Case Info
This is a continuation of copending application Ser. No. 07/764,418 filed on Sep. 23, 1991 which issued on Nov. 17, 1992, as U.S. Pat. No. 5,164,347, which was a continuation of U.S. patent application Ser. No. 07/327,296, filed on Mar. 22, 1989, which issued on Sep. 24, 1991, as U.S. Pat. No. 5,051,383, which was a continuation-in-part of U.S. Patent application Ser. No. 06/907,928, filed on Sep. 16, 1986, which issued on Nov. 21, 1989, as U.S. Pat. No. 4,882,306, in the names of Christopher R. Kennedy et al., the contents of which are expressly incorporated herein by reference.
US Referenced Citations (17)
Foreign Referenced Citations (3)
Number |
Date |
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0116809 |
Aug 1984 |
EPX |
0155831 |
Sep 1985 |
EPX |
0169067 |
Jan 1986 |
EPX |
Non-Patent Literature Citations (2)
Entry |
"Oxidation of Molten Aluminum Alloys, Reaction with Refractories"--M. Drouzy and M. Richard--Mar., 1974 Fonderie, France No. 332 pp. 121-128. |
"Refractories for Aluminum Alloy Melting Furnaces"--B. Clavaud and V. Jost--Sep., 1980--Lillian Brassinga (from French) Jan. 1985. |
Continuations (2)
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Date |
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764418 |
Sep 1991 |
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Parent |
327296 |
Mar 1989 |
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Continuation in Parts (1)
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Number |
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907928 |
Sep 1986 |
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