A method for manufacturing a C/C part includes fabricating an oxidized PAN fiber preform comprising a stack of sheets of multi-axial, non-crimp, OPF fabric. The method includes positioning the oxidized PAN fiber preform with a female forming tool, the female forming tool comprising a die recess, and forming the oxidized PAN fiber preform into a shaped body. The shaped body is removed from the female forming tool and moved into a graphite fixture for carbonization. The carbonized shaped body may also be densified into the final C/C part. The carbonized shaped body can also be placed in a perforated graphite fixture for densification and removed from the perforated graphite fixture between densification processes for machining and for facilitating further densification.

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 forming a ceramic matrix composite component includes forming a fiber preform, the fiber preform including a plurality of ceramic fiber plies, a non-reduced fiber region having an areal weight, and a reduced fiber region characterized by a reduced areal weight less than the areal weight of the non-reduced fiber region by at least 5 percent. The method further includes selectively applying ceramic particles to the reduced fiber region in such manner as to avoid applying the ceramic particles to the non-reduced fiber region, and subsequently densifying the preform.

An abrasive particle can include a coating overlying at least a portion of a core. In an embodiment, the coating can include a first portion overlying at least a portion of the core and a second portion overlying at least a portion of the core, wherein the first portion can include a ceramic material and the second portion can include a silane or a silane reaction product. In a particular embodiment, the first portion can consist essentially of silica. In another particular embodiment, the first portion can include a surface roughness of not greater than 5 nm and a crystalline content of not greater than 60%.

An automated preparation method of a SiC.sub.f/SiC composite flame tube, comprising the following steps: preparing an interface layer for a SiC fiber by a chemical vapor infiltration process, and obtaining the SiC fiber with a continuous interface layer; laying a unidirectional tape on the SiC fiber with the continuous interface layer and winding the SiC fiber with the continuous interface layer to form and obtaining a preform of a net size molding according to a fiber volume and a fiber orientation obtained in a simulation calculation; and adopting a reactive melt infiltration process and the chemical vapor infiltration process successively for a densification and obtaining a high-density SiC.sub.f/SiC composite flame tube in a full intelligent way. The SiC.sub.f/SiC composite flame tube prepared by the present disclosure not only has a high temperature resistance, but also has a low thermal expansion coefficient, high thermal conductivity and high thermal shock resistance.

A method of treating at least one silicon carbide fibre, the method including a) formation of a silica layer at the surface of a silicon carbide fibre having an oxygen content less than or equal to 1% in atomic percentage, the silica layer being formed by contacting this fibre with an oxidizing medium having a temperature greater than or equal to 50° C. and pressure greater than or equal to 1 MPa, and b) removal of the silica layer formed by hydrothermal treatment of the fibre obtained after implementation of step a) in which the fibre is treated with water at a pressure between saturating vapour pressure and 30 MPa and at a temperature less than or equal to 400° C.

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 ceramic matrix composite includes a ceramic matrix, fibers embedded in the ceramic matrix, and an interfacial coating system on each of the fibers. The interfacial coating system includes alternating layers of boron nitride layers of individual thicknesses of about 50 nanometers to 200 nanometers and carbon layers of individual thicknesses of less than 5 nanometers.

A method of manufacturing ceramic matrix composites includes producing chemical vapor deposition functionalized ceramic particles before injecting the functionalized ceramic particles into the CMC fabric. The functionalized ceramic particles are mixed with a binder solution and then dispensed into voids present between adjacent tows of the CMC fabric. Injecting the particles in the center of the voids reduces the size and volume fraction of the voids/defects, improving the homogeneity of surface texture, homogeneity of microstructure, and part model shape conformity.

A method for producing a hollow part made of a ceramic matrix composite material. The method includes shaping a hollow fibrous preform. A core of oxidizable material is housed or inserted into the preform. The method also includes consolidating the preform and extracting the core by oxidising the core.