Abstract: A net shaped ceramic-reinforced aluminum matrix composite is produced by forming a permeable mass of ceramic material with a defined surface boundary having a barrier, and contacting a molten aluminum-magnesium alloy with the permeable mass of ceramic material in the presence of a gas comprising from about 10 to 100% nitrogen, by volume, balance nonoxidizing gas, e.g. hydrogen or argon. Under these conditions, the molten alloy spontaneously infiltrates the ceramic mass under normal atmospheric pressures until it reaches the barrier. A solid body of the alloy can be placed adjacent to a permeable bedding of ceramic material having a barrier, and brought to the molten state, preferably to at least about 700.degree. C., in order to form the net shape aluminum matrix composite by spontaneous infiltration. In addition to magnesium, auxiliary alloying elements may be employed with aluminum. The resulting composite products may contain a discontinuous aluminum nitride phase in the aluminum matrix.

Abstract: In the present invention, there is provided a method for producing a self-supporting ceramic or ceramic composite body by the oxidation of a parent metal to form a polycrystalline ceramic material comprising the oxidation reaction product of said parent metal with an oxidant, including a vapor-phase oxidant, and optionally one or more metallic constituents dispersed throughout the polycrystalline ceramic material. The method comprises the steps of providing at least a portion of said parent metal with a barrier means at least partially spaced from said parent metal for establishing at least one surface of the ceramic body, and heating said parent metal to a temperature above its melting point but below the melting point of the oxidation reaction product to form a body of molten metal. At that temperature, the molten metal is reacted with the oxidant, thus forming the oxidation reaction product.

Abstract: The invention relates to a method for producing ceramic composites obtained by oxidation of a parent metal to form a polycrystalline ceramic material by providing a filler having a coating of a silicon source on at least a portion of the filler different in composition from the primary composition of the filler, said silicon source possessing intrinsic doping properties. A body of molten parent metal, adjacent a mass of the filler material, reacts with an oxidant to form an oxidation reaction product which infiltrates the adjacent mass of filler, thereby forming the ceramic composite.

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 having a chemical composition which is different from 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 of making self-supporting ceramic composite structures having filler embedded therein includes infiltrating a permeable mass of filler with polycrystalline material comprising an oxidation reaction product obtained by oxidation of a parent metal such as aluminum and optionally containing therein non-oxidized constituents of the parent metal. The structure is formed by placing a parent metal adjacent to a permeable filler and heating the assembly to melt the parent metal and provide a molten body of parent metal which is contacted with a suitable vapor-phase oxidant. Within a certain temperature region and optionally aided by one or more dopants in or on the parent metal, molten parent metal will migrate through previously formed oxidation reaction product into contact with the oxidant, causing the oxidation reaction product to grow so as to embed the adjacent filler and provide the composite structure.

Abstract: The present invention relates to a novel method of manufacturing a composite body, such as a ZrB.sub.2 -ZrC-Zr composite body, by utilizing a carburization technique. Moreover, the invention relates to novel products made according to the process. The novel process modifies the residual parent metal which remains in a composite body, by exposing said residual metal to a carburizing environment. Thus, by modifying the composition of residual parent metal, the properties of the resultant composite body can also be modified. Parent metals such as zirconium, titanium, and hafnium are well suited to be treated by the carburizing process according to the present invention.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron nitride material typically resulting in a body comprising a boron-containing compound, a nitrogen-containing compound and metal. The mass to be infiltrated may contain one or more inert fillers admixed with the boron nitride, to produce a composite by reactive infiltration, which composite comprises a matrix which embeds the filler material. The matrix, in a composite body containing filler material, comprises one or more metal, a boron-containing compound and a nitrogen-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal and/or porosity. The mass to be infiltrated can be contained within a refractory vessel having a venting means included therein.

Abstract: A method for producing a self-supporting ceramic composite structure, which includes 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 with an oxidant and, optionally, one or more metallic constituents, and the filler embedded by the matrix. The method includes heating a first source of molten parent metal and a reservoir source of molten parent metal and contacting the first source of molten parent metal with a permeable bedding of filler. The first source of molten parent metal is reacted with the oxidant to form the oxidation reaction product and is replenished from 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 of producing self-supporting ceramic or ceramic composite bodies having a polymer component, which includes first providing a self-supporting ceramic or ceramic composite 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 or ceramic composite body originally formed.

Abstract: A method for manufacture of Group IVB metal carbide ceramic composites is provided wherein a permeable mass of filler and carbon is contacted with a molten Group IVB metal. The molten metal is maintained in contact with the permeable mass for a sufficient period to infiltrate the permeable mass and to react the molten metal with the carbon source to form a Group IVB metal carbide composite. The permeable mass may comprise a Group IVB metal carbide, or other inert filler, or a combination of filler materials.

Abstract: A method is provided for producing a self-supporting ceramic composite body having a plurality of spaced apart wall members, each wall member having a bounded cross-section for defining substantially continuous, fluid passageways. The wall members generally inversely replicate in opposed directions the geometry of a positive pattern. Each of the wall members, which are axially aligned, comprises a ceramic matrix having a filler embedded therein, and is obtained by the oxdiation reaction of a parent metal to form a polycrystalline material which comprises the oxidation reaction product of the parent metal with an oxidant and, optionally, one or more metals, e.g. nonoxidized constituents of the parent metal.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron carbide material which may contain one or both of a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron carbide material, boron-containing compound and/or carbon-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron donor material and a carbon material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron donor material and carbon donor material. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.

Abstract: There is provided a method for producing a self-supporting ceramic composite comprising (1) a ceramic matrix obtained by oxidation of an aluminum zinc alloy to form a polycrystalline oxidation reaction product of the metal with an oxidant, and (2) one or more fillers embedded by the matrix. The metal alloy and permeable mass of filler having at least one defined surface boundary are oriented relative to each other so that formation of the oxidation reaction product will occur into said mass of filler and in a direction towards said defined surface boundary. On heating the metal to a first temperature above its melting point but below the melting point of said oxidation reaction product to form a body of molten parent metal, the molten metal reacts with said oxidant to form said oxidation reaction product which infiltrates said mass of filler to said defined surface boundary.

Abstract: An aluminum metal matrix composite comprises an aluminum metal matrix embedding a second filter, such as a ceramic second filler, and is formed by contacting, for example, a molten aluminum metal with a permeable mass of second filler within a ceramic impervious mold formed by growing a polycrystalline oxidation reaction product into a first filler. By hermetically sealing the second filler within the mold with a body of molten aluminum metal, the latter spontaneously infiltrates the mass of second filler at moderate temperatures, e.g. about 900.degree. C., without need of any other infiltration expedients. The molten mass containing the infiltrated ceramic filler is solidified to provide the metal matrix composite which may be recovered from the mold.

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: 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 metal 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 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 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: A method of making self-supporting ceramic composite structures having filler embedded therein includes infiltrating a permeable mass of filler with polycrystalline material comprising an oxidation reaction product obtained by oxidation of a parent metal such as aluminum and optionally containing therein non-oxidized constituents of the parent metal. The structure is formed by placing a parent metal adjacent to a permeable filler and heating the assembly to melt the parent metal and provide a molten body of parent metal which is contacted with a suitable vapor-phase oxidant. Within a certain temperature region and optionally aided by one or more dopants in or on the parent metal, molten parent metal will migrate through previously formed oxidation reaction product into contact with the oxidant, causing the oxidation reaction product to grow so as to embed the adjacent filler and provide the composite structure.

Abstract: This invention relates to a new ceramic-metal composite body and a method for producing the same. Particularly, a compliant layer composition is utilized for preventing the rupture of a ceramic article and/or the yielding or failure of a metal during the pouring, solidification and cooling of a molten metal which has been cast around the ceramic. A slurry composition for the compliant layer includes plaster of paris, a liquid vehicle and a filler material. The slurry composition is coated on the ceramic article and thereafter is heat-treated to form a compliant layer. Ceramic-metal composite bodies comprising low strength hollow articles and high expansion coefficient metals may be manufactured according to the method of this invention.