Abstract: The present invention relates to a process of depositing metals onto various substrates. Applications for which the present invention may be useful include the formation of catalysts such as those used in electrochemical applications, including fuel cells and the like, refining applications such as oil refining, automotive applications such as automotive catalytic converters, and other similar applications.

Abstract: Coated ceramic filler materials comprised of ceramic particles, fibers, whiskers, etc. having at least two substantially continuous coatings thereon are provided. The coatings are selected so that the interfacial shear strength between the ceramic filler material and the first coating, between coatings, or between the outer coating and the surrounding matrix material, are not equal so as to permit debonding and pull-our when fracture occurs. The resultant, multi-coated ceramic filler materials may be employed to provide composites, especially ceramic matrix composites, with increased fracture toughness. The ceramic filler materials are designed to be particularly compatible with ceramic matrices formed by directed oxidation of precursor metals, but such ceramic filler materials are also adaptable for use in many other composite material systems.In a preferred embodiment, the coatings are applied to the ceramic fiber plies or preforms by CVD.

Abstract: This invention relates generally to a novel directed metal oxidation process which is utilized to produce self-supporting bodies. In some of the more specific aspects of the invention, a parent metal (e.g., a parent metal vapor) is induced to react with at least one solid oxidant-containing material to result in the directed growth of a reaction product which is formed from a reaction between the parent metal and the solid oxidant-containing material. The inventive process can be utilized to form bodies having substantially homogeneous compositions, graded compositions, and macrocomposite bodies. In a preferred embodiment, the reaction product may be chemically modified or a different reaction product may be coated thereon. Specifically, once a first reaction product is formed on a solid oxidant-containing material, the formed body may be exposed to a vapor-phase parent metal different from the first parent metal.

Abstract: The present invention relates to novel methods for shaping a filler material into a porous preform and subsequently filling at least a portion of the porous preform with a second material to form a composite body. Specific aspects of the invention include novel combinations of materials to form the preform in combination with novel processing techniques for shaping the combinations of materials into a porous preform.

Abstract: The present invention relates, generally, to a self-supporting porous ceramic composite body and to methods for producing such articles to net or near net shape, which bodies exhibit superior thermal and mechanical properties. The invention also relates to the manufacture of ceramic-metal or ceramic-ceramic macrocomposite bodies which have the porous ceramic articles incorporated therein or thereon.

Abstract: A silicon carbide ceramic having crystalline grain boundary phases is prepared by heating a composition comprising silicon carbide, a silicate glass and a high metal content transition metal silicide, to a temperature of 1300.degree. C. to 2100.degree. C. under vacuum until oxygen is removed from the glass as SiO gas, and the glass that remains within the silicon carbide ceramic crystallizes.

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. The self-supporting ceramic composite structure optionally contains 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 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 the discovery of organometallic ceramic precursor binders used to fabricate shaped bodies by different techniques. Exemplary shape making techniques which utilize hardenable, liquid, organometallic, ceramic precursor binders include the fabrication of negatives of parts to be made (e.g., sand molds and sand cores for metalcasting, etc.), as well as utilizing ceramic precursor binders to make shapes directly (e.g., brake shoes, brake pads, clutch parts, grinding wheels, polymer concrete, refractory patches and liners, etc.). In a preferred embodiment, this invention relates to thermosettable, liquid ceramic precursors which provide suitable-strength sand molds and sand cores at very low binder levels and which, upon exposure to molten metalcasting exhibit low emissions toxicity as a result of their high char yields of ceramic upon exposure to heat. Another preferred embodiment of the invention involves the fabrication of preforms used in the formation of composite articles.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies and novel products produced by the method. Particularly, a permeable mass of filler material or a preform is provided which has included therein at least some matrix metal powder. Moreover, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with the filler material or preform, at least at some point during the process, which permits molten matrix metal, upon contact with the filler material or preform, to spontaneously infiltrate the filler material or preform. The presence of powdered matrix metal in the preform or filler material reduces the relative volume fraction of filler material to matrix metal.

Abstract: The present invention broadly relates to novel aluminum nitride matrix ceramic composite bodies for use as refractory materials and methods for making the same. The refractory materials are useful in environments which are corrosive, erosive, abrasive and/or which generate thermal shock. Such environments include furnaces, and associated apparatus which house or contact molten masses including, for example, molten metals, molten glasses, etc. The preferred method for making the aluminum nitride matrix ceramic composites comprises a directed oxidation of molten metal.

Abstract: The compositions of this invention comprise uncrosslinked reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one metal-containing polymer comprising a metal-nitrogen polymer.Preferred compositions of this invention comprise reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one of: silicon-nitrogen polymers, aluminum-nitrogen polymers and boron-nitrogen and polymer combinations thereof comprising a multiplicity of sequentially bonded repeat units the compositions comprising the reaction products of the reaction mixtures, and the compositions obtained by crosslinking the reaction products of the reaction mixtures. The crosslinking may be effected through at least one of thermal-based, radiation-based free radical-based or ionic-based crosslinking mechanisms.

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 in the metallic constituent.

Abstract: This invention relates to metal and ceramic matrix composite brake rotors comprising an interconnected matrix embedding at least one filler material. In the case of metal matrix composite materials, the at least one filler material comprises at least about 26% by volume of the brake rotor for most applications, and at least about 20% by volume for applications involving passenger cars and trucks. In a preferred embodiment of the present invention, the metal matrix composite brake rotor comprises an interconnected metal matrix containing at least about 28% by volume of a particulate filler material and more preferably at least about 30% by volume. Moreover, the composite rotors of the present invention exhibit a maximum operating temperature of at least about 900.degree. F. and preferably at least about 950.degree. F. and even more preferably at least about 975.degree. F. and higher.

Abstract: The present invention relates to the formation of a metal matrix composite body by the spontaneous infiltration of a molten matrix metal into a three-dimensionally interconnected material. Moreover, the three-dimensionally interconnected material may contain filler material within at least a portion of its porosity. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with a filler material and/or a three-dimensionally interconnected material and/or a matrix metal at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the three-dimensionally interconnected material and any filler material contained within at least a portion of the porosity of the three-dimensionally interconnected material.

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 infiltation of the filler material or preform, the infiltrated material is bonded to the second material, thereby forming a macrocomposite body.

Abstract: The compositions of this invention comprise uncrosslinked reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one metal-containing polymer comprising a metal-nitrogen polymer.Preferred compositions of this invention comprise reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one of: silicon-nitrogen polymers, aluminum-nitrogen polymers and boron-nitrogen and polymer combinations thereof comprising a multiplicity of sequentially bonded repeat units the compositions comprising the reaction products of the reaction mixtures, and the compositions obtained by crosslinking the reaction products of the reaction mixtures. The crosslinking may be effected through at least one of thermal-based, radiation-based free radical-based or ionic-based crosslinking mechanisms.

Abstract: This invention relates generally to a novel method of manufacturing a composite body and to novel products made thereby. More particularly, the invention relates to a method of producing a self-supporting composite body comprising one or more boron-containing compounds, e.g., a boride or a boride and carbide, by reactive infiltration of molten parent metal into a bed or mass containing boron carbide, and, optionally, one or more inert fillers and permitting residual or excess parent metal to remain bonded to the formed self-supporting composite body. The residual or excess metal is used to form a bond between the formed composite body and another body (e.g., a metal body, a ceramic body, or another composite body). In addition, this invention related to alternative methods of disposing metal on at least one surface of the above-described composite bodies (such as sputtering, CVD, etc.) to permit the composite bodies to be bonded to another body.

Abstract: The compositions of this invention comprise uncrosslinked reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one metal-containing polymer.Preferred compositions of this invention comprise reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one of: at least one of: a polymer selected from the group consisting of silicon-nitrogen polymers, aluminum-nitrogen polymers and boron-nitrogen polymers comprising a multiplicity of sequentially bonded repeat units.

Abstract: The present invention generally relates to mechanisms for preventing undesirable oxidation (i.e., oxidation protection mechanisms) of reinforcement materials in composite bodies. The oxidation protection mechanisms include getterer materials which are added to the composite body which gather or scavenge undesirable oxidants which may enter the composite body. The getterer materials may be placed into at least a portion of the composite body such that any undesirable oxidant approaching, for example, a fiber reinforcement, would be scavenged by (e.g., reacted with) the getterer. In a preferred embodiment of the present invention, the getterer material(s) form at least one compound (e.g., at least one glassy material) which acts as a crack sealant, thereby further enhancing the oxidation protection of the composite body. One or more ceramic filler materials which serve as reinforcements may have a plurality of superimposed coatings thereon, at least one of which coatings may function as a getterer.

Abstract: The present invention relates to a novel process for forming thin metal matrix composite bodies. Particularly, an infiltration enhancer and/or an infiltrating atmosphere are in communication with a filler material or preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. Such spontaneous infiltration occurs without the application of any pressure or vacuum. In an embodiment of the present invention, the filler material may be sprayed upon a thin sheet of matrix metal. Alternatively, the filler material may be shaped via tape casting, slip casting, etc. to provide a thin preform. In another embodiment of the present invention, a body of matrix metal may be coated with a filler material such that upon spontaneous infiltration a metal matrix composite body is produced which inversely replicates the configuration of the original body of matrix metal.