A ceramic powder for a ceramic component, in particular based on zirconia and/or alumina, in particular for a timepiece or jewelry piece. The powder includes at least one noble metal among platinum, rhodium, osmium, palladium, ruthenium and iridium, at a quantity of less than or equal to 5% by weight.

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.

The invention relates to a process for preparing silicon-containing composite particles in a fluidized bed. Porous conductive particles having a defined particle size and pore structure are combined with a particulate additive having defined particle size, density and BET surface area. The combined porous conductive particles and particulate additive are subjected to chemical vapour infiltration in a fluidised bed to cause deposition of silicon in the pores of the porous conductive particles.

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.

A method of infiltrating a fiber preform comprises positioning an assembly in a process chamber, where the assembly includes a tool comprising through-holes, a fiber preform constrained within the tool, and a sacrificial preform disposed between the fiber preform and the tool. The sacrificial preform is gas permeable. The process chamber is heated, and gaseous reactants are delivered into the process chamber during the heating. The gaseous reactants penetrate the through-holes of the tool and infiltrate the sacrificial preform and the fiber preform. Deposition of reaction products occurs on exposed surfaces of the fiber preform and the sacrificial preform, and a coating is formed thereon. In addition, the sacrificial preform accumulates excess coating material formed from increased reactions at short diffusion depths. Accordingly, the coating formed on the fiber preform exhibits a thickness variation of about 10% or less throughout a volume of the fiber preform.

A fiber comprises a bulk material comprising: one or more of carbon, silicon, boron, silicon carbide, and boron nitride; and a metal or metal alloy whose affinity for oxygen is greater than that of the bulk material. At least a first portion of the metal or metal alloy is present at the entrance to grain boundaries at the surface of the fiber and within the fiber to a depth of at least 1 micron from the fiber surface. A method of improving a fiber comprises heating a fiber in an inert atmosphere to 900-1300 C for sufficient time to allow at least some of a metal or metal alloy, placed on the fiber, to diffuse and/or flow into and along grain boundaries to a depth of at least 1 micron. The metal or metal alloy has a greater affinity for oxygen than that of the fiber bulk material.

A cubic boron nitride sintered material includes: more than or equal to 20 volume % and less than 80 volume % of cubic boron nitride grains; and more than 20 volume % and less than or equal to 80 volume % of a binder phase, and when a carbon content is measured from a cubic boron nitride grain into the binder phase in a direction perpendicular to an interface between the cubic boron nitride grain and the binder phase using TEM-EDX, a first region having a carbon content larger than an average value of a carbon content of the binder phase exists, the interface exists in the first region, and a length of the first region is more than or equal to 0.1 nm and less than or equal to 10 nm.

A method for densifying one or more porous substrates with pyrolytic carbon by chemical vapour infiltration, includes admitting, at the inlet of the densification furnace, a reactive gaseous phase including at least one pyrolytic carbon precursor; reacting at least a fraction of the reactive gaseous phase with the porous substrate or substrates; extracting, at the outlet of the densification furnace, gaseous effluents originating from the reactive gaseous phase; reintroducing, with the reactive gaseous phase admitted at the inlet of the densification furnace, at least a fraction of the gaseous effluents extracted at the outlet of the furnace, wherein the fraction of the gaseous effluents introduced with the reactive gaseous phase includes at least one polyaromatic hydrocarbon compound.

Disclosed is a ceramic matrix component having a fibrous core and a ceramic matrix composite shell surrounding at least a portion of the fibrous core. The ceramic matrix composite shell comprises a fibrous preform. The fibrous core has a greater porosity than the fibrous preform. A method of making the ceramic matrix component is also disclosed.

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.