C04B2235/5248

PARTICLE BASED INSERTS FOR CMC
20230047461 · 2023-02-16 ·

A method for forming a ceramic matrix composite component includes forming a fibrous preform of the component with a plurality of fiber layers and a fill region disposed between one or more of the plurality of fiber layers. Ceramic particles are provided in the fill region, which is densified using chemical vapor infiltration.

Process for depositing a coating on short fibres by calefaction

A process for depositing a coating on short fibres of carbon or silicon carbide from a coating precursor, the short fibres having a length of between 50 μm and 5 mm, the process including at least heating the short fibres by placing a mixture including the fibres and a liquid phase of the coating precursor in a microwave field so as to bring the surface of the fibres to a temperature allowing the coating on the fibres from the coating precursor to be formed by calefaction.

Indirect laser brazing of SiC/SiC CMCs for manufacturing and repair

A method of connecting two CMC substrates that includes providing two substrates; placing one substrate approximate to the other substrate, such that at least a portion of the two substrates overlap and define a brazing area; placing a brazing material approximate the brazing area; defining a primary raster pattern that encompasses the brazing area and a portion of the two substrates outside the brazing area; defining a secondary raster pattern that encompasses the brazing area; allowing a laser to scan the primary raster pattern to preheat the brazing area to a temperature below the brazing material's melting point; allowing the laser to scan the secondary raster pattern to heat the brazing area to a temperature that is above the brazing material's melting point; melting and allowing the brazing material to flow within the brazing area; and cooling the brazing area to form a brazed joint connecting the two substrates.

CMC component with integral cooling channels and method of manufacture

A fiber-reinforced component for use in a gas turbine engine includes a first braided fiber sleeve forming a cooling channel and a plurality of fiber plies enclosing the first braided fiber sleeve, with the plurality of fiber plies forming first and second walls separated by the first braided fiber sleeve. The fiber-reinforced component further includes a matrix material between fibers of the braided fiber sleeve and the plurality of fiber plies.

Method of manufacturing CMC components using boron carbide
11578774 · 2023-02-14 · ·

A method of manufacturing a ceramic matrix composite component includes pressure casting a fibrous preform with a slurry comprising boron carbide and densifying the fibrous preform using a liquid source of carbon. The method may include forming holes in the fibrous preform before pressure casting the fibrous preform with the slurry. The method may also include sintering the boron carbide after the pressure casting. In various embodiments, the sintering may be performed before the densifying.

Production method incorporating particles containing silicon
11554989 · 2023-01-17 · ·

A production method is provided in which submicronic particles containing silicon are incorporated into a matrix, wherein, during the incorporation of the particles, the particles are in a compacted state with a bulk density of more than 0.10 grams per cubic centimeter, and the compacted particles have a specific surface area at least 70% of that of the particles considered separately without contact between each other.

METHOD FOR MAKING A PASSIVATING COATING BASED ON ONE OR MORE SILICON COMPOUNDS ON A CERAMIC MATRIX COMPOSITE REINFORCED WITH CARBON FIBRES AND CERAMIC MATRIX COMPOSITE REINFORCED WITH CARBON FIBRES WITH SUCH COATING

A method makes a silicon compound-based passivating coating on a ceramic matrix composite reinforced with carbon fibers. A piece made in a ceramic matrix composite reinforced with carbon fibers is placed in a closed chamber of an oven. A predefined load of solid silicon is placed in the chamber avoiding direct contact between the silicon and the piece. The oven is heated while maintaining inside the chamber predefined medium/low vacuum conditions, to generate silicon vapors inside the chamber. The vapors react with substances on the surface of the piece to form a surface coating having composites of the substances with the silicon. The partial pressure of the vacuum, temperature inside the chamber and exposure times of the piece to the silicon vapors to obtain a predefined thickness of the surface coating are chosen. The piece is cooled once the predefined thickness of the passivating coating is reached.

METHOD FOR MAKING A PASSIVATING COATING BASED ON ONE OR MORE SILICON COMPOUNDS ON A CERAMIC MATRIX COMPOSITE REINFORCED WITH CARBON FIBRES AND CERAMIC MATRIX COMPOSITE REINFORCED WITH CARBON FIBRES WITH SUCH COATING

A method makes a silicon compound-based passivating coating on a ceramic matrix composite reinforced with carbon fibers. A piece made in a ceramic matrix composite reinforced with carbon fibers is placed in a closed chamber of an oven. A predefined load of solid silicon is placed in the chamber avoiding direct contact between the silicon and the piece. The oven is heated while maintaining inside the chamber predefined medium/low vacuum conditions, to generate silicon vapors inside the chamber. The vapors react with substances on the surface of the piece to form a surface coating having composites of the substances with the silicon. The partial pressure of the vacuum, temperature inside the chamber and exposure times of the piece to the silicon vapors to obtain a predefined thickness of the surface coating are chosen. The piece is cooled once the predefined thickness of the passivating coating is reached.

COMPOSITES AND METHODS OF FORMING COMPOSITES HAVING TAILORED HARDNESS PROFILE
20230234331 · 2023-07-27 · ·

An aerospace component may comprise a fiber reinforced composite material. The fiber reinforced composite material includes a plurality of fiber layers and a carbon matrix surrounding the plurality of fiber layers. A plurality of ceramic particles is dispersed in the carbon matrix. A first fiber layer of the plurality of fiber layers may include a carbon fiber, and a second fiber layer of the plurality of fiber layers may include a non-carbon fiber. A hardness of the non-carbon fiber is greater than a hardness of carbon fiber.

Microstructured fiber interface coatings for composites

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.