Abstract:
The present invention relates to a method of using a novel ceramic composite body. Particularly, the ceramic composite body comprises an oxidation reaction product of a parent metal which forms a polycrystalline matrix embedding a filler material (e.g., silicon carbide particles). The ceramic composite body shows unexpected and desirable results when subjected to thermal shock.
Abstract:
There is disclosed methods for producing self-supporting ceramic matrix and ceramic matrix composite bodies by batch, semi-continuous, and continuous processes utilizing the directed oxidation of a molten parent metal (15) with an oxidant to form an oxidation reaction product which may embed filler material.
Abstract:
The present invention relates to a novel process for forming metal matrix composite bodies. Particularly, a suitable matrix metal (33), typically in a molten state, is in contact with a suitable filler material (31) or preform in the presence of a suitable reactive atmosphere in an impermeable container (32), at least at some point during the process, which permits a reaction to occur between the reactive atmosphere and the molten matrix metal (33) and /or filler material (31) or preform and/or impermeable container (32), thereby causing molten matrix metal (33) to infiltrate the filler material (31) or preform due to, at least in part, the creation of a self-generated vacuum. Such self-generated vacuum infiltration occurs without the application of any external pressure or vacuum.
Abstract:
There is disclosed methods for producing self-supporting ceramic matrix and ceramic matrix composite bodies by batch, semi-continuous, and continuous processes utilizing the directed oxidation of a molten parent metal (15) with an oxidant to form an oxidation reaction product which may embed filler material.
Abstract:
The present invention relates to a novel method of manufacturing a composite body, such as a ZrB₂-ZrC-Zr composite body, by utilizing a post-treatment technique. Moreover, the invention relates to novel products made according to the process. The novel process modifies at least a portion (10) of a composite body by exposing said body to a source of second metal.
Abstract:
Self-supporting bodies are produced by reactive infiltration of a parent metal (10) into a boron nitride material (12) 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 (12), 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 of 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:
Self-supporting bodies are produced by reactive infiltration of a parent metal (10) into 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 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:
Self-supporting bodies are produced by reactive infiltration of a parent metal (10) into boron carbide (12) typically resulting in a composite comprising a boron-containing compound and metal. The mass to be infiltrated may contain one or more inert fillers admixed with the boron carbide (12), or at least one carbon donor material, to produce a composite by reactive infiltration, which composite comprises a matrix of metal and boron-containing compound embedding the filler. 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 (16) having a venting means included therein.
Abstract:
The present invention relates to a novel method for forming metal matrix composite bodies and the novel products produced therefrom. A negative shape or cavity, which is complementary to the desired metal matrix composite body to be produced, is first formed. The formed cavity is thereafter filled with a permeable mass of filler material (7). Molten matrix metal (8) is then induced to spontaneously infiltrate the filled cavity. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the filler material (7), at least at some point during the process, which permits the matrix metal (8) when made molten, to spontaneously infiltrate the permeable mass of filler material (7), which at some point during the processing, may become self-supporting. In a preferred embodiment, cavities can be produced by a process which is similar to the so-called lost-wax process.