摘要:
Whisker-reinforced ceramic matrix composites comprising a principal crystal phase selected from the group of anorthite, barium-stuffed cordierite, and mixed cordierite/anorthite are prepared by extrusion of extrudable ceramic batches comprising an extrusion vehicle and a solids component consisting essentially of inorganic whiskers and powdered glass, the glass being a thermally crystallizable glass containing an internal nucleant and capable of being consolidated at ambient pressures or above to a dense consolidated preform which may be converted to a substantially glass-free whisker-reinforced ceramic matrix composite by thermal treatment.
摘要:
Semiconductor-on-insulator (SOI) structures, including large area SOI structures, are provided which have one or more regions composed of a layer (15) of a substantially single-crystal semiconductor (e.g., doped silicon) attached to a support substrate (20) composed of an oxide glass or an oxide glass-ceramic. The oxide glass or oxide glass-ceramic is preferably transparent and preferably has a strain point of less than 1000° C., a resistivity at 250° C. that is less than or equal to 1016 Ω-cm, and contains positive ions (e.g., alkali or alkaline-earth ions) which can move within the glass or glass-ceramic in response to an electric field at elevated temperatures (e.g., 300-1000° C.). The bond strength between the semiconductor layer (15) and the support substrate (20) is preferably at least 8 joules/meter2. The semiconductor layer (15) can include a hybrid region (16) in which the semiconductor material has reacted with oxygen ions originating from the glass or glass-ceramic. The support substrate (20) preferably includes a depletion region (23) which has a reduced concentration of the mobile positive ions.
摘要:
An activated carbon body having flow-through channels and method of making the body. The method involves combining and shaping channel-forming material and optionally fugitive pore-forming material and non-fugitive support material, and a crosslinkable resin into a green body and curing the resin. The temperature at which the channel-forming material begins to distort is greater than the curing temperature of the resin. The resin is carbonized and at the same time the channel-forming material is vaporized out to form a carbon body having flow through channels in the configuration of the fugitive material. The carbon body is then activated. Among other shapes the channels can be straight, curved or crisscrossed.
摘要:
A process for forming a silicon carbide structure includes molding by compression a mixture of a silicon precursor powder and a cross-linking thermoset resin to form a rigid structure, carbonizing the rigid structure, and forming a silicon carbide structure by heating the carbonized rigid structure at a temperature sufficient to allow carbon and silicon in the structure to react to form silicon carbide.
摘要:
A silicon carbide honeycomb body is made by shaping a plasticizable raw material batch mixture containing powdered silicon metal, a water soluble crosslinking thermoset resin, a powdered silicon-containing filler, a water soluble thermoplastic binder, and water into a green honeycomb body, and thereafter drying, curing and sintering the green body at a temperature sufficient to convert the green body to a porous silicon carbide sintered body.
摘要:
A composite including an inorganic substrate having an outer surface from which pores extend into the substrate and a coating extending over the substrate's outer surface as a substantially uninterrupted layer of carbon. The coating penetrates into the pores of the inorganic substrate. The composite can be made by a process including the steps of contacting an inorganic substrate with a coating and impregnating liquid consisting essentially or wholly of a carbon precursor liquid, treating the inorganic substrate under conditions effective to cure substantially the carbon precursor liquid, and heating the inorganic substrate under conditions effective to convert substantially the cured carbon precursor liquid to carbon.
摘要:
The channel-plugging of porous ceramic honeycombs to provide wall flow filter bodies therefrom is carried out using water-based cements comprising ceramic powders and soluble alkali metal silicates; the cements form durable plugs that are resistant to thermal and chemical damage upon drying and without firing.
摘要:
A method for making an activated carbon composite which involves providing a crosslinkable resin and a support material which is wettable by the resin. The support material can be cotton, chopped wood, sisal, non-fugitive material, and combinations of these. The support is contacted with the resin; and the resin and support material are dried. The resin and support material are then shaped, the resin is cured, and the resin and any carbonizable material are carbonized. The carbon is then activated to produce the product composite. An activated carbon composite produced by the above described method in which the carbon is in the form of a continuous structure reinforced by and uniformly distributed throughout non-fugitive support material.
摘要:
Semiconductor-on-insulator (SOI) structures, including large area SOI structures, are provided which have one or more regions composed of a layer of a substantially single-crystal semiconductor (e.g., doped silicon) attached to a support substrate composed of an oxide glass or an oxide glass-ceramic. The oxide glass or oxide glass-ceramic is preferably transparent and preferably has a strain point of less than 1000° C., a resistivity at 250° C. that is less than or equal to 1016 Ω-cm, and contains positive ions (e.g., alkali or alkaline-earth ions) which can move within the glass or glass-ceramic in response to an electric field at elevated temperatures (e.g., 300-1000° C.). The bond strength between the semiconductor layer and the support substrate is preferably at least 8 joules/meter2. The semiconductor layer can include a hybrid region in which the semiconductor material has reacted with oxygen ions originating from the glass or glass-ceramic. The support substrate preferably includes a depletion region which has a reduced concentration of the mobile positive ions.
摘要:
Semiconductor-on-insulator (SOI) structures, including large area SOI structures, are provided which have one or more regions composed of a layer (15) of a substantially single-crystal semiconductor (e.g., doped silicon) attached to a support substrate (20) composed of an oxide glass or an oxide glass-ceramic. The oxide glass or oxide glass-ceramic is preferably transparent and preferably has a strain point of less than 1000° C., a resistivity at 250° C. that is less than or equal to 1016 Ω-cm, and contains positive ions (e.g., alkali or alkaline-earth ions) which can move within the glass or glass-ceramic in response to an electric field at elevated temperatures (e.g., 300-1000° C.). The bond strength between the semiconductor layer (15) and the support substrate (20) is preferably at least 8 joules/meter2. The semiconductor layer (15) can include a hybrid region (16) in which the semiconductor material has reacted with oxygen ions originating from the glass or glass-ceramic. The support substrate (20) preferably includes a depletion region (23) which has a reduced concentration of the mobile positive ions.