Abstract: A self-supporting ceramic composite body produced by a method which comprises preparing a polycrystalline material as the oxidation reaction product of a parent metal with a vapor-phase oxidant, comminuting the resulting material to a particulate, forming a permeable mass of said particulate as filler, and infiltrating said particulate with an oxidation reaction product of a parent metal with a vapor-phase oxidant, thereby forming said ceramic composite body.

Abstract: A method of producing self-supporting ceramic bodies having a modified metal-containing component includes first providing a self-supporting ceramic body comprising (i) a polycrystalline oxidation reaction product formed upon oxidation of a molten parent metal precursor with an oxidant, and (ii) an interconnected metal-containing component at least partially accessible from one or more surfaces of said ceramic body. The surface or surfaces of the ceramic body is contacted with a quantity of foreign metal different from said interconnected metal-containing component at a temperature and for a time sufficient to allow for interdiffusion, whereby at least a portion of said metal-containing component is displaced by said foreign metal. The resulting ceramic body, having an altered metal-containing component, exhibits modified or improved properties.

Abstract: Novel self-supporting ceramic structures are produced by the oxidation reaction of a molten metal precursor with a vapor-phase oxidant to form an oxidation reaction product. Molten metal is drawn through the oxidation reaction product towards the oxidant to cause continued growth of the product at the interface between oxidant and previously formed product. This reaction or growth is continued to form a thick, self-supporting ceramic body. The resulting ceramic material of the polycrystalline growth product consists essentially of an oxidation reaction product and, optionally, one or more non-oxidized constituents of the metal precursor.

Abstract: A self-supporting ceramic body having a polymer component, which includes first providing a self-supporting ceramic body comprising (i) a polycrystalline oxidation reaction product formed upon oxidation of a molten parent metal with an oxidant, and (ii) interconnected porosity at least partially accessible from one or more surfaces of said ceramic body. The polymer is disposed or formed within the interconnected porosity. The polymer is situated so as to alter, modify or contribute to the properties of the ceramic body originally formed.

Abstract: Self-supporting ceramic bodies having a modified metal-containing component are formed by first providing a self-supporting ceramic body comprising (1) a polycrystalline oxidation reaction product formed upon oxidation of a molten parent metal precursor with an oxidant, and (ii) an interconnected metal-containing component at least partially accessible from one or more surfaces of said ceramic body. The surface or surfaces of the ceramic body are contacted with a quantity of foreign metal different from said interconnected metal-containing component at a temperature and for a time sufficient to allow for interdiffusion, whereby at least a portion of said metal-containing component is displaced by said foreign metal. The resulting ceramic body, having an altered metal-containing component, exhibits modified or improved properties.

Abstract: Ceramic bodies are bonded together via a layer of an oxidation reaction product of a molten metal, which metal is present in one or both of the ceramic bodies prior to bonding. At least one of the ceramic bodies comprises a ceramic product formed by the oxidation reaction of molten parent metal (e.g., alumina from molten aluminum) and grown as molten metal is transported through, and oxidized on the surface of, its own oxidation product. One or both of the ceramic bodies used in the bonding process contains surface-accessible channels of residual metal, i.e., metal channels which have resulted from molten-metal transport during the ceramic growth process. When the suitably assembled ceramic bodies are heated in the presence of an oxidant at a temperature above the melting point of the residual metal, molten metal at the surface of at least one of the body ceramic bodies reacts with the oxidant to form a layer of oxidation reaction product, which may or may not incorporate at least one filler material.

Abstract: In the present invention there is provided a method for producing abrasive ceramic and ceramic composite material characterized by an abrasive grain as the comminuted form of a polycrystalline ceramic material. The abrasive grains of the present invention consist essentially of the oxidation reaction product of a parent materal precursor with a vapor phase oxidant, and, optionally one or more metallic constituents such as non-oxidized constituents of the parent metal. There is also provided a method for producing abrasive grains which additionally consist of one or more inert filler materials.

Abstract: A complex oxidation reaction product of two or more metals in an oxidized state is formed by positioning a suitable precursor metal adjacent to a permeable mass of a metal-containing compound in an oxidizing atmosphere and heating the assembly to form a body of molten precursor metal. The molten metal infiltrates the permeable mass and reacts therewith and with the oxidizing atmosphere to form a complex oxidation reaction product. Methods for determining the shape of the resulting article are described. The disclosed methods can be used to form superconducting perovskites.

Abstract: A method for producing a self-supporting ceramic composite structure comprising a ceramic matrix embedding a filler, includes oxidizing a parent metal to form a polycrystalline material comprising the oxidation reaction product of the parent metal and, optionally, one or more metallic constituents. The method includes heating the parent metal to provide a source of molten parent metal and a reservoir of molten metal which is in communication with the parent metal and contacting the molten parent metal with a permeable bedding of filler. The molten parent metal reacts with the oxidant to form the oxidation reaction product and is replenished by the reservoir as the reacting continues for a time sufficient to grow the oxidation reaction product to a desired extent and thereby embed at least a portion of the bedding of filler within the oxidation reaction product to form the ceramic composite structure.

Abstract: A method to produce an article of commerce comprising a self-supporting ceramic body by oxidation of a molten parent metal with a vapor-phase oxidant, includes applying to a surface of the parent metal a layer having at least one dopant material therein. The layer is thin relative to the thickness of the ceramic body. Upon heating the parent metal to a molten state in the presence of the oxidant, e.g., air, an oxidation reaction product is formed on the molten metal which, because of the effect of the dopant material, migrates through the growing oxidation reaction product so as to be exposed to the oxidant to form additional oxidation reaction product to and beyond the depth of the applied dopant material layer. Suitable temperature and oxidizing conditions are maintained for a time sufficient to produce a self-supporting ceramic body.

Abstract: The invention comprises a method of making self-supporting ceramic and ceramic composite structures by the oxidation reaction of a body of molten parent metal precursor with a vapor-phase oxidant to form an oxidation reaction product. This reaction or growth is continued to form a thick, self-supporting ceramic or ceramic composite body. The body is recovered and in a separate subsequent operation, at least a portion of a surface is coated with one or more materials in order to effect desired changes in the properties of the surface, e.g., hardness, corrosion resistance.

Abstract: A self-supporting ceramic composite body produced by a method body which comprises preparing a polycrystalline material as the oxidation reaction product of a parent metal with a vapor-phase oxidant, comminuting the resulting material to a particulate, forming a permeable mass of said particulate as filler, and infiltrating said particulate with an oxidation reaction product of a parent metal with a vapor-phase oxidant, thereby forming said ceramic composite body.

Abstract: A method of producing a self-supporting ceramic composite body having therein at least one cavity which inversely replicates the geometry of a positive mold of parent metal. The method includes embedding the mold of parent metal within a conformable bed of filler to provide therein a cavity shaped and filled by the mold. The assembly is heated to melt the parent metal mold, e.g., an aluminum parent metal mold, and contacted with an oxidant to oxidize the molten parent metal to form a polycrystalline material which grows through the surrounding bed of filler, the molten metal being drawn through the growing polycrystalline material to be oxidized at the interface between the oxidant and previously formed oxidation reaction product whereby the cavity formerly filled by the mold of parent metal is eventually evacuated of the metal. There remains behind a cavity whose shape inversely replicates the original shape of the mold.

Abstract: In a method for producing ceramic body by oxidation of a parent metal having a graded microstructure characterized by a plurality of zones differing from each other in one or more properties by altering the process conditions during formation of said ceramic body such that a zone of the oxidation reaction product formed posterior to said altering has one or more properties different from a zone of the oxidation reaction product formed anterior to said altering.

Abstract: An assembly for the preparation of ceramic composite structures includes a segmented container within which a permeable filler is retained and a parent metal body is contacted with the bed of permeable filler. The segmented container is comprised of one or more segments made of a material, such as an inconnel alloy, which has a coefficient of thermal expansion which is significantly greater than that of the filler. The segments are arranged to defined between or among them one or more expansion joints which are effective to accommodate circumferential thermal expansion of the segments to thereby inhibit or prevent volumetric expansion of the container. A method of forming ceramic composite structures includes heating the resulting assembly in the presence of an oxidant to melt and oxidize the parent metal, e.g., aluminum, to form a polycrystalline material comprising an oxidation reaction product which grows through the mass of filler to embed it and thus form the composite structure.

Abstract: The present invention relates to the formation of a macrocomposite body by spontaneously infiltrating a permeable mass of filler material or a preform with molten matrix metal and bonding the spontaneously infiltrated material to at least one second material such as a ceramic or ceramic containing body and/or a metal or metal containing body. Particularly, an infiltration enhancer and/or infiltration enhancer precursor and/or infiltrating atmosphere are in communication with a filler material or a preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. Moreover, prior to infiltration, the filler material or preform is placed into contact with at least a portion of a second material such that after infiltration of the filler material or preform, the infiltrated material is bonded to the second material, thereby forming a macrocomposite body.

Abstract: The present invention provides a method for producing a self-supporting ceramic composite by the oxidation of a parent metal to form a polycrystalline ceramic material consisting essentially of the oxidation reaction product of the parent metal with an oxidant, including a vapor-phase oxidant, and, optionally, one or more metallic constituents. A permeable filler material, such as a preform, with at least one surface bearing a permeable stratum, is contacted with a body of molten parent metal heated to a temperature above its melting point but below the melting point of the oxidation reaction product.

Abstract: A method of producing a self-supporting ceramic or ceramic composite structures which includes providing a first self-supporting ceramic or ceramic composite body comprising (i) a polycrystalline oxidation reaction product formed upon oxidation of a first molten parent metal with a first oxidant, and (ii) interconnected porosity at least partially accessible from one or more surfaces of said first ceramic body. A second ceramic body is used to form, by reaction with an oxidant, a second polycrystalline material which is infiltrated into the porosity of at least a portion of said first ceramic body.

Abstract: A method of producing self-supporting ceramic composite bodies of desired shape by infiltrating a permeable self supporting preform with polycrystalline matrix material comprising an oxidation reaction product obtained by oxidation of a parent metal precursor, such as aluminum, and optionally containing therein metallic constituents. The composite body is formed by contacting a zone of a permeable self supporting preform, having at least one defined surface boundary spaced from said contacting zone, with a body of molten metal which is reacted with a suitable vapor-phase oxidant to form an oxidation reaction product.

Abstract: There is disclosed a method for producing a self-supporting ceramic body by oxidation of a molten precursor metal with a vapor-phase oxidant to form an oxidation reaction product and inducing a molten flux comprising said molten precursor metal through said oxidation reaction product. A second metal is incorporated into said molten flux during the oxidation reaction. The resulting ceramic body includes sufficient second metal such that one or more properties of said ceramic body are at least partially affected by the presence and properties of said second metal.