C04B2237/38

SEAL COATS TO PREVENT SILICON LOSS DURING RE-MELT INFILTRATION OF SI CONTAINING COMPOSITES
20200199028 · 2020-06-25 ·

Provided is a method including obtaining ceramic matrix composite (CMC) with a first matrix portion including a silicon carbide and silicon phase dispersed therewithin, disposing a coating thereupon to form a sealed part, and forming thereupon another segment comprising a CMC, which may be another matrix portion including a silicon carbide and a silicon phase dispersed within therewithin. Also provided is a gas turbine component with a CMC segment including a matrix portion including a silicon carbide and a silicon phase dispersed therewithin, a sealing layer including silicon carbide enclosing the first segment, and a second segment on the sealing layer, wherein the second segment includes a melt-infiltrated CMC having a matrix portion including a silicon carbide and a silicon phase dispersed therewithin.

SELF-HEALING MATRIX FOR A CERAMIC COMPOSITE

A method for forming a self-healing ceramic matrix composite (CMC) component includes depositing a first self-healing particulate material in a first region of a CMC preform of the CMC component and depositing a second self-healing particulate material having a different chemical composition than the first self-healing particulate material in a second region of the CMC preform distinct from the first region.

Composite airfoil assembly for an interdigitated rotor
10677075 · 2020-06-09 · ·

Rotor assemblies and methods for manufacturing airfoils for rotor assemblies are provided. For example, a rotor assembly comprises a rotary structure extending circumferentially about an axial centerline of a gas turbine engine, an airfoil having a root and a tip, and a pin extending through the root. The root is coupled to the rotary structure and has a bulbous shape, and the airfoil is formed from a plurality of composite plies. The pin defines both a planar first surface and a planar second surface on a pin body having a generally circular cross-section. Further, the pin includes a first end and a second end that contact the rotary structure. The first and second surfaces together form a point that is oriented toward the tip of the airfoil. In one embodiment, the rotary structure is an outer rotor of an interdigitated rotor assembly and the airfoil extends radially inward.

TURBINE BLADE ASSEMBLY INCLUDING MULTIPLE CERAMIC MATRIX COMPOSITE COMPONENTS
20200173293 · 2020-06-04 ·

A turbine blade having an airfoil portion includes a first ceramic matrix composite (CMC) component having a first outer surface and a second ceramic matrix composite (CMC) component having a second outer surface. The second CMC component is positioned adjacent the first CMC component such that the first outer surface and the second outer surface align with one another and at least partially define the airfoil portion. A ceramic bead is at least partially formed at an interface between the first CMC component and the second CMC component. The formation of the bead melts a portion of the first CMC component and the second CMC component, such that the ceramic bead, the first CMC component, and the second CMC component become a single contiguous component and the bead fixedly attaches the first CMC component and the second CMC component. The bead includes a bead outer surface that extends outward beyond the first outer surface and the second outer surface and an overlayer is deposited onto the airfoil portion, the overlayer bonded to the first outer surface, the second outer surface, and the bead outer surface.

Method for joining dissimilar engine components

A method for joining engine components includes positioning a first plurality of thermal protection structures across a thermal protection space between a first thermal protection surface and a second thermal protection surface. The first and second engine components are locally joined by forming a first plurality of transient liquid phase (TLP) or partial transient liquid phase (PTLP) bonds along corresponding ones of the first plurality of thermal protection structures between the first thermal protection surface and the second thermal protection surface. The second thermal protection surface is formed from a second surface material different from a first surface material of the first thermal protection surface.

INTEGRAL CERAMIC MATRIX COMPOSITE FASTENER WITH NON-POLYMER RIGIDIZATION
20200147835 · 2020-05-14 ·

A method of forming an integral fastener for a ceramic matrix composite component comprises the steps of forming a fiber preform with an opening, forming a fiber fastener, inserting the fiber fastener into the opening, and infiltrating a matrix material into the fiber preform and fiber fastener to form a ceramic matrix composite component with an integral fastener. A gas turbine engine is also disclosed.

ACCELERATED CVI DENSIFICATION OF CMC THROUGH INFILTRATION

A process for densification of a ceramic matrix composite comprises forming a reinforcing ceramic continuous fiber stack having a central zone bounded by an outer zone adjacent; locating first particles within the central zone; coating the first particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; locating second particles within the outer zone; coating the second particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; forming the stack into a predetermined three dimensional shape; and densifying the stack.

Systems and methods for manufacturing prepreg tapes

Systems and methods for manufacturing unidirectional fiber prepreg tapes for CMC articles are provided. In one exemplary aspect, the method includes casting a matrix material on a carrier film to form a matrix film. The matrix material of the matrix film is then allowed to dry for a predetermined time. The matrix film is then wrapped on a drum and the matrix material is wet to a predetermined viscosity with a solvent. Thereafter, a fiber tow that includes of a plurality of fibers is wound about the drum so that the fiber tow penetrates into the matrix material and the matrix material impregnates the fiber tow to form the prepreg tape.

CERAMIC MATRIX COMPOSITE TURBINE NOZZLE SHELL AND METHOD OF ASSEMBLY

A method of manufacturing a ceramic matrix composite (CMC) turbine nozzle shell is provided. The method includes: assembling a primary outer nozzle platform, a primary inner nozzle platform, a core and trailing edge preform, and an airfoil-shaped body; joining the primary outer nozzle platform to a secondary outer nozzle platform of the airfoil-shaped body; and joining the primary inner nozzle platform to a secondary inner nozzle platform of the airfoil-shaped body. Composite plies circumferentially surround the airfoil-shaped body, and their longitudinal edges are cut into fingers that are folded down. The fingers are interleaved between secondary platform plies to form the secondary outer and inner nozzle platforms.

CERAMIC MATRIX COMPOSITE TURBINE NOZZLE SHELL AND METHOD OF ASSEMBLY

A ceramic matrix composite turbine nozzle includes a primary outer nozzle platform; a primary inner nozzle platform; and an airfoil-shaped body extending between the primary inner and primary outer nozzle platforms. The body includes core plies defining a cavity; composite wrap plies circumscribing the core plies and defining an airfoil shape; a secondary outer nozzle platform in contact with the primary outer nozzle platform; and a secondary inner nozzle platform in contact with the primary inner nozzle platform. Each composite wrap ply has two layers of unidirectional fibers oriented transverse to each other and has first and second longitudinal edges. The first and second longitudinal edges are cut into fingers, which are folded in a transverse direction away from a turbine nozzle longitudinal axis and are interleaved between platform plies to define the secondary inner nozzle platform and the secondary outer nozzle platform.