Thermally-conductive ceramic and ceramic composite components suitable for high temperature applications, systems having such components, and methods of manufacturing such components. The thermally-conductive components are formed by a displacive compensation of porosity (DCP) process and are suitable for use at operating temperatures above 600 C. without a significant reduction in thermal and mechanical properties.

Thermally-conductive ceramic and ceramic composite components suitable for high temperature applications, systems having such components, and methods of manufacturing such components. The thermally-conductive components are formed by a displacive compensation of porosity (DCP) process and are suitable for use at operating temperatures above 600 C. without a significant reduction in thermal and mechanical properties.

A method for a mechanical treatment of a concrete floor, such as troweling and blade finishing, using a hand-operated, a walk-behind or a ride-on actuator, such as a concrete power trowel machine, a floor treatment machine or the like, is described. The actuator has one or more operating heads comprising a rotor consisting of two or more attachment arms. The floor surface is treated by means of concrete troweling elements, such as circular trowel pans or elongated trowel blades attached to the rotor attachment arms, made substantially of plastic material, that are detachably coupled to the rotor of the actuator, in particular to prevent discoloration of the treated floor surface during treatment. Before the concrete floor is troweled with plastic-based concrete troweling elements, a water-soluble silica-based medium is applied on it.

A method for a mechanical treatment of a concrete floor, such as troweling and blade finishing, using a hand-operated, a walk-behind or a ride-on actuator, such as a concrete power trowel machine, a floor treatment machine or the like, is described. The actuator has one or more operating heads comprising a rotor consisting of two or more attachment arms. The floor surface is treated by means of concrete troweling elements, such as circular trowel pans or elongated trowel blades attached to the rotor attachment arms, made substantially of plastic material, that are detachably coupled to the rotor of the actuator, in particular to prevent discoloration of the treated floor surface during treatment. Before the concrete floor is troweled with plastic-based concrete troweling elements, a water-soluble silica-based medium is applied on it.

A device includes a ceramic substrate formed of a first material, a polishable layer formed of a different material, and an interface between the ceramic substrate and the polishable layer. The interface is formed by infiltration of molten elemental silicon, and bonds the ceramic substrate and the polishable layer together. The device may include an optical device such as, for example, mirror or a beam dump. A method of making a device from a green-state structure and a polishable layer is also disclosed. The method includes infiltrating elemental silicon into and through the green-state structure, to form a substrate of a multi-phase ceramic material from the green-state structure, and to reactively bond the substrate and the polishable layer together.

A device includes a ceramic substrate formed of a first material, a polishable layer formed of a different material, and an interface between the ceramic substrate and the polishable layer. The interface is formed by infiltration of molten elemental silicon, and bonds the ceramic substrate and the polishable layer together. The device may include an optical device such as, for example, mirror or a beam dump. A method of making a device from a green-state structure and a polishable layer is also disclosed. The method includes infiltrating elemental silicon into and through the green-state structure, to form a substrate of a multi-phase ceramic material from the green-state structure, and to reactively bond the substrate and the polishable layer together.

A method for preparing a ceramic-modified carbon-carbon composite material. The method includes preparing and thermally treating a carbon fiber preform, and depositing pyrolytic carbon on the carbon fiber preform in a chemical vapor infiltration furnace, to yield a porous carbon-carbon composite material; placing the carbon-carbon composite material deposited with the pyrolytic carbon on a zirconium-titanium powder mixture, and performing a reactive melt infiltration, to yield a carbon-carbon composite material modified by non-stoichiometric zirconium titanium carbide; and placing the carbon-carbon composite material modified by non-stoichiometric zirconium titanium carbide in a powder mixture including carbon, boron carbide, silicon carbide, silicon, and an infiltration enhancer, and performing an embedding method, to form a ceramic-modified carbon-carbon composite material.

A method for preparing a ceramic-modified carbon-carbon composite material. The method includes preparing and thermally treating a carbon fiber preform, and depositing pyrolytic carbon on the carbon fiber preform in a chemical vapor infiltration furnace, to yield a porous carbon-carbon composite material; placing the carbon-carbon composite material deposited with the pyrolytic carbon on a zirconium-titanium powder mixture, and performing a reactive melt infiltration, to yield a carbon-carbon composite material modified by non-stoichiometric zirconium titanium carbide; and placing the carbon-carbon composite material modified by non-stoichiometric zirconium titanium carbide in a powder mixture including carbon, boron carbide, silicon carbide, silicon, and an infiltration enhancer, and performing an embedding method, to form a ceramic-modified carbon-carbon composite material.

A method of treating a ceramic surface containing zirconia, whereby the ceramic surface is ablated by directing a laser beam with a diameter of 200-400 m produced by a CO.sub.2 laser with a pulse frequency of 1200-1800 Hz onto the ceramic surface, and a N.sub.2 assist gas is concurrently applied with a pressure of 550-650 KPa co-axially with the laser beam to form an ablated ceramic surface comprising microgrooves with ZrN present on a surface of the microgrooves, wherein the ablated ceramic surface has a higher surface hydrophobicity than the ceramic surface prior to the ablating.

Methods for forming ceramic cores are disclosed. A ceramic core formed using the method of the present application includes a silica depletion zone encapsulating an inner zone. The inner zone includes mullite and the silica depletion zone includes alumina. The method includes heat-treating a ceramic body in a non-oxidizing atmospheric condition for an effective temperature and time combination at a pressure less than 10 atmosphere to form the silica depletion zone at a surface of the ceramic core.