A method of separating a mixture of used refractory components of different chemistry types obtained from a demolished refractory includes hydrating the mixture of refractory components to destructively hydrate at least some components of the mixture of refractory components, and separating, based on size, the at least some components from other components of the mixture of refractory components.

Disclosed herein is a chemical vapor infiltration method including flowing ceramic precursors through a preform and depositing a matrix material on the preform at a first gas infiltration pressure, increasing the gas filtration pressure to a second gas infiltration pressure, and lowering the gas infiltration pressure to a third gas infiltration pressure which is intermediate to the first and second gas infiltration pressures.

Disclosed is a method of coating a high temperature fiber including depositing a base material on the high temperature fiber using atomic layer deposition, depositing an intermediate material precursor on the base material using molecular layer deposition, depositing a top material on the intermediate material precursor or the intermediate layer using atomic layer deposition, and heat treating the intermediate precursor. The intermediate material in the final coating includes a structural defect, has lower density than the top material or a combination thereof. Also disclosed are the coated high temperature fiber and a composite including the high temperature fiber.

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.

A shape forming tool for pre-carbonization compression of a fibrous preform is provided, comprising a female forming tool, a first plug, a second plug, and a wedge, each configured to be received by a die recess of the female forming tool. A first tapered surface of the wedge is configured to engage the first plug and the second tapered surface of the wedge is configured to engage the second plug. In response to the first tapered surface of the wedge engaging the first plug and the second tapered surface of the wedge engaging the second plug, the first plug and the second plug, respectively, are configured to move laterally towards opposing sides of the female forming tool and/or vertically toward a bottom side of the female forming tool to compress the fibrous preform into a shaped body.

A process for manufacturing pyrocarbon, includes forming pyrocarbon by a calefaction process from at least one C.sub.2 to C.sub.6 alcohol or polyalcohol precursor, the precursor being ethanol, rough laminar pyrocarbon being obtained by imposing a temperature of between 1250° C. and 1325° C. during calefaction.

A process for manufacturing a friction component made of composite material, includes the densification of a fibrous preform of carbon yarns by a matrix including at least pyrocarbon and at least one ZrO.sub.xC.sub.y phase, where 1≤x≤2 and 0≤y≤1, the matrix being formed by chemical vapor infiltration at least from a first gaseous precursor of pyrocarbon and a second gaseous precursor including zirconium, the second precursor being an alcohol or a C.sub.1 to C.sub.6 polyalcohol modified by linking the oxygen atom of at least one alcohol function to a group of formula —Zr—R.sub.3, the substituents R being identical or different, and R being selected from: —H, C.sub.1 to C.sub.5 carbon chains and halogen atoms.

The present invention relates to a SiC composite and a method for manufacturing the same. More particularly, the present invention relates to a slurry composition for ceramic matrix composites which can not only reduce the number of precursor impregnation pyrolysis (PIP) cycles but also be useful in the PIP process to increase hardness, thermal stability, and relative density.

A method for making a ceramic matrix composite component includes densifying a fibrous preform of the component with a ceramic matrix to form an intermediate component; infiltrating a hole in the intermediate component with an infiltrate material comprising a solid and a metallic alloy whose reaction forms a carbide, silicide, boride or combination thereof, heating the infiltrate material to a temperature in excess of a melting point of the metallic alloy; and sequentially cooling regions of the hole starting from an interior end of the hole to the outer surface of the intermediate component to form a solidified through-thickness reinforcement element. The hole extends in a through-thickness direction and is open to an exterior surface of the intermediate component.

A method for forming a high temperature coating includes applying carbon powder to a surface of a carbon/carbon (C/C) composite substrate to force the carbon powder into one or more surface voids of the surface of the C/C composite substrate. The carbon powder has a substantially same composition and morphology as a surface portion of the C/C composite substrate. The method includes applying a metal slurry to the surface of the C/C composite substrate following the application of the carbon powder and reacting a metal of the metal slurry with carbon of the carbon powder and carbon of the surface portion of the C/C composite substrate to form a metal-rich antioxidant layer of a metal carbide on the C/C composite substrate.