A process for manufacturing a ceramic matrix composite part, includes infiltrating a fibrous structure including a powder composition with a melt infiltration composition including at least silicon in order to form a ceramic matrix in the porosity of the fibrous structure, the powder composition including at least silicon carbide particles, wherein the silicon carbide particles have a bimodal size distribution with a first set of silicon carbide particles having a first average size and a second set of silicon carbide particles having a second average size smaller than the first average size, the number of particles in the first set being greater than the number of particles in the second set.

A process for manufacturing a composite material part including a particulate reinforcement densified by a ceramic matrix, the process including: formation of a blank of the part to be manufactured by shaping a mixture including a binder, first ceramic or carbon particles intended to form the particulate reinforcement of the part and second ceramic or carbon particles distinct from the first particles, removal or pyrolysis of the binder present in the blank to obtain a porous preform of the part to be manufactured, and infiltration of the porosity of the preform by a molten composition including a metal in order to obtain the part.

A method of producing a core-shell particle includes introducing a barium titanate-based base powder and an additive to a reactor, and exposing the barium titanate-based base powder and the additive to a thermal plasma torch to obtain core-shell particles including a core portion having barium titanate (BaTiO.sub.3) and a shell portion including the additive and formed on a surface of the core portion.

A method of producing a CMC having a smooth surface includes forming a fiber preform; rigidizing the preform with an interphase coating; infiltrating a ceramic slurry into the preform to form a green body; conducting secondary operations on the green body; applying a slurry-based layer onto a portion of the green body; and infiltrating the green body with a molten silicon or silicon alloy, such that the CMC exhibits a smooth surface. The application of the slurry-based surface layer onto the green body includes placing the green body into a tool fixture having upper and lower components, such that a gap is present between the green body and at least one of the upper and lower components; and delivering a surface layer slurry into at least one gap, such that the surface layer slurry forms the slurry-based layer on at least a portion of the green body.

A method of producing a CMC component that includes forming a preform having a plurality of ceramic fiber plies with each ply occupying a predetermined position; rigidizing the preform with a fiber interphase coating; inspecting the preform to determine which of the plies has partially or fully delaminated; reworking the delaminated plies in the preform; infiltrating a ceramic slurry into the preform to form a green body; optionally, conducting a secondary operation on the green body; and infiltrating the green body with a molten silicon or silicon alloy to form the CMC component. The step of reworking delaminated plies may also be applied to a green body formed after ceramic slurry infiltration into a rigidized fiber preform.

The present invention relates to a method for preparing a fully ceramic capsulated nuclear fuel material containing three-layer-structured isotropic nuclear fuel particles coated with a ceramic having a composition which has a higher shrinkage than a matrix in order to prevent cracking of ceramic nuclear fuel, wherein the three-layer-structured nuclear fuel particles before coating is included in the range of between 5 and 40 fractions by volume based on after sintering. More specifically, the present invention provides a composition for preparing a fully ceramic capsulated nuclear fuel containing three-layer-structured isotropic particles coated with the substance which includes, as a main ingredient, a silicon carbine derived from a precursor of the silicon carbide wherein a condition of ΔL.sub.c>ΔL.sub.m at normal pressure sintering is created, where the sintering shrinkage of the coating layer of the three-layer-structured isotropic nuclear fuel particles is ΔL.sub.c and the sintering shrinkage of the silicon carbide matrix is ΔL.sub.m; material produced therefrom; and a method for manufacturing the material. The residual porosity of the fully ceramic capsulated nuclear fuel material is 4% or less.

A method of fabricating a composite part, includes forming a fiber preform for the part that is to be obtained by depositing a plurality of fiber structures impregnated with a thermoplastic polymer onto a surface, with deposition being performed by automated fiber placement; eliminating the thermoplastic polymer present in the preform by dissolution with a solvent; and injecting a liquid impregnation composition into the pores of the fiber preform after eliminating the thermoplastic polymer in order to form a matrix in the pores of the fiber preform.

A method of fabricating a brake component made from a ceramic matrix composite is disclosed. In various embodiments, the method includes infiltrating a carbon fabric with a slurry containing a ceramic powder and a sintering aid; laying up the carbon fabric in a desired geometry to form a raw component; warm pressing the raw component to form a green component; and sintering the green component via a spark plasma sintering process to form a sintered component.

Disclosed is a coated ceramic fiber including a zirconium interface coating layer deposited on the ceramic fiber, a zirconium dioxide interface coating layer adjacent to the zirconium interface coating layer, and an additional interface coating layer adjacent to the zirconium dioxide interface coating layer, wherein zirconium dioxide interface coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

Disclosed is a coated ceramic fiber including a silicon carbide coating layer adjacent to the ceramic fiber and a silicon dioxide coating layer adjacent to the silicon carbide coating layer, wherein the silicon dioxide coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.