In various embodiments, a process is described for the preparation of a concrete mixture in a Ready-mix or for an installation. A quantity of amorphous silica is added with an average particle size in the range of from about 1 to about 55 nanometers and/or wherein the surface area of the particles of the amorphous silica is in the range of from about 50 to about 900 m2/g. The amorphous silica may be added in colloidal form or otherwise, and is added at a particular stage to ensure efficacy.

A method for repairing a target member including a ceramic matrix composite reinforced by ceramic fiber includes: a removal step of removing at least a part of a surface of the target member; an arrangement step of arranging a green body for repair which includes the ceramic fiber on a portion where the surface is removed in the removal step; an impregnation step of impregnating at least the portion of the target member where the green body for repair is disposed with slurry; and a sintering step of sintering the target member on which the green body for repair is disposed, after the impregnation step.

A process for manufacturing an abradable layer, includes compressing a powder composition including at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], and sintering the powder composition thus compressed to obtain the abradable layer, wherein a temperature imposed during sintering, the sintering time and the compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.

Disclosed is a method of spraying a surface with a set-delayed cement. The method comprises providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; spraying a surface with the set-delayed cement composition; and allowing the set-delayed cement composition to set on the surface.

In various embodiments, a process is described for the preparation of a concrete mixture in a Ready-mix or for an installation. A quantity of amorphous silica is added with an average particle size in the range of from about 1 to about 55 nanometers and/or wherein the surface area of the particles of the amorphous silica is in the range of from about 50 to about 900 m2/g. The amorphous silica may be added in colloidal form or otherwise, and is added at a particular stage to ensure efficacy.

A method and apparatus for providing molten metal infiltration into a component is provided.

Electromechanical devices and methods of forming coating layers thereon are provided. The electromechanical devices include components each having one or more surfaces formed of one or more metallic materials and susceptible to operating environments having temperatures in excess of 150 C. for a long term, and electrically insulative coating layers formed on the one or more surfaces of the components. The coating layer is configured to survive in operating environments having temperatures in excess of 180 C. for a long term.

In various embodiments, a process is described for the preparation of a concrete mixture in a Ready-mix or for an installation. A quantity of amorphous silica is added with an average particle size in the range of from about 1 to about 55 nanometers and/or wherein the surface area of the particles of the amorphous silica is in the range of from about 50 to about 900 m.sup.2/g. The amorphous silica may be added in colloidal form or otherwise, and is added at a particular stage to ensure efficacy.

A process for manufacturing an abradable layer, includes compressing a powder composition including at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], and sintering the powder composition thus compressed to obtain the abradable layer, wherein a temperature imposed during sintering, the sintering time and the compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.

A densified carbon-carbon composite material exhibits superior strength and toughness, relative to low density carbon-carbon composites. The process densification of a set of carbon fibers with a non-fibrous carbon material, resulting in a precursor carbon matrix, stabilizing the precursor carbon matrix, resulting in a stabilized carbon matrix, and densifying the stabilized carbon matrix using a field assisted sintering technology (FAST) process, resulting in the high density carbon-carbon composite material.