Abstract: A gas turbine engine blade includes a platform, an airfoil section extending from the platform in a first direction, a mount extending from the platform in a second direction opposite the first direction, and a damper deposited on one of the platform, the airfoil section, and the mount. A method of sizing a damper for a gas turbine engine blade is also disclosed.

Abstract: A method of forming a ceramic matrix composite includes arranging a plurality of fibers into a preform, each of the plurality of fibers being formed from silicon carbide, depositing a nucleating layer on the plurality of fibers, the nucleating layer comprising a crystalline material having an a-lattice constant and a c-lattice constant, and depositing a boron nitride layer on the nucleating layer. The c-lattice constant of the crystalline material of the nucleating layer corresponds to an a-lattice constant of the silicon carbide, such that the c-lattice constant of the crystalline material is within 3.0% of the a-lattice constant of the silicon carbide.

Abstract: A reactor furnace for coating fiber tow includes an elongate reactor having a fiber tow inlet and a fiber tow outlet; a thermo-chemical reactor section positioned along the elongate reactor; a first microwave source for directing microwave energy along the reactor from a first end of the reactor toward a second end of the reactor; a second microwave source for directing microwave energy along the reactor from the second end of the reactor toward the first end of the reactor; a gas inlet upstream of the thermo-chemical reactor; and a gas outlet downstream of the thermo-chemical reactor.

Abstract: A ceramic matrix composite includes a plurality of ceramic fibers, an interface coating disposed on the plurality of ceramic fibers, and a ceramic matrix surrounding the plurality of ceramic fibers. The ceramic matrix includes a silicon carbide phase and an oxide phase. The oxide phase includes at least two of cordierite, mullite, sapphirine, spinel, alumina, periclase, and forsterite. A method of fabricating a ceramic matrix composite is also disclosed.

Abstract: A method of manufacturing a heat exchanger core from glass ceramic matrix composite includes placing one or more reinforcing fibers around one or more mandrels into a mold cavity. A glass matrix material infiltrates the one or more reinforcing fibers to produce an infiltrated core and the one or more mandrels is removed to create one or more passages passing through the infiltrated core.

Abstract: A method for coating a fiber tow includes moving a fiber tow across a wedge to separate the fiber tow into a plurality of sub-tows, and coating the plurality of sub-tows.

Abstract: A method of spreading fiber tows includes applying a coupling medium to a surface of a fibrous structure, positioning an ultrasonic probe adjacent to the surface of a fibrous structure, such that a tip of the ultrasonic probe is in contact with the coupling medium, moving at least one of the ultrasonic probe and the fabric structure relative to the other of the ultrasonic probe and the fibrous structure according to a first pattern, and imparting ultrasonic vibration with the ultrasonic probe to the surface of the fibrous structure while moving the ultrasonic probe along the surface of the fibrous structure. Imparting ultrasonic vibration to the surface of the fibrous structure spreads tows of the fibrous structure.

Abstract: A reactor furnace for coating fiber tow includes an elongate reactor having a fiber tow inlet and a fiber tow outlet; a thermo-chemical reactor section positioned along the elongate reactor; a first microwave source for directing microwave energy along the reactor from a first end of the reactor toward a second end of the reactor; a second microwave source for directing microwave energy along the reactor from the second end of the reactor toward the first end of the reactor; a gas inlet upstream of the thermo-chemical reactor; and a gas outlet downstream of the thermo-chemical reactor.

Abstract: A method of forming a ceramic matrix composite includes arranging a plurality of fibers into a preform, each of the plurality of fibers being formed from silicon carbide, depositing a nucleating layer on the plurality of fibers, the nucleating layer comprising a crystalline material having an a-lattice constant and a c-lattice constant, and depositing a boron nitride layer on the nucleating layer. The c-lattice constant of the crystalline material of the nucleating layer corresponds to an a-lattice constant of the silicon carbide, such that the c-lattice constant of the crystalline material is within 3.0% of the a-lattice constant of the silicon carbide.

Abstract: A gas turbine engine blade includes a platform, an airfoil section extending from the platform in a first direction, a mount extending from the platform in a second direction opposite the first direction, and a damper deposited on one of the platform, the airfoil section, and the mount. A method of sizing a damper for a gas turbine engine blade is also disclosed.

Abstract: In accordance with at least one aspect of this disclosure, a pump system for an aircraft includes, a cylinder barrel configured to rotate within a pump housing of a pump, and a plurality of pistons seated within a respective bore defined in the cylinder barrel. Each piston further includes a piston ring disposed at an end thereof configured to form a hydrodynamic seal with an inner surface of the respective bore. Each respective piston ring is of silicon nitride. In embodiments, the piston ring can include a chamfer on at least a leading edge of the piston ring. In embodiments, the piston ring can include a cut therethrough configured to allow for thermal expansion of the piston ring.

Abstract: A method of forming a part includes forming a glass-ceramic matrix composite material to form a pre-consolidated feedstock sheet with a pre-determined shape. The pre-consolidated feedstock sheet is sectioned into a first piece of pre-consolidated feedstock sheet and a second piece of pre-consolidated feedstock sheet. The first piece of pre-consolidated feedstock sheet and a second piece of pre-consolidated feedstock sheet are assembled with a second piece of pre-consolidated feedstock sheet to form a composite layup. The first piece of pre-consolidated feedstock sheet and the second piece of pre-consolidated feedstock sheet are joined by compressing the composite layup to form a glass-ceramic matrix composite part.

Abstract: A reactor furnace for coating fiber tow includes an elongate reactor having a fiber tow inlet and a fiber tow outlet; a thermo-chemical reactor section positioned along the elongate reactor; a first microwave source for directing microwave energy along the reactor from a first end of the reactor toward a second end of the reactor; a second microwave source for directing microwave energy along the reactor from the second end of the reactor toward the first end of the reactor; a gas inlet upstream of the thermo-chemical reactor; and a gas outlet downstream of the thermo-chemical reactor.

Abstract: A method of coating a seal slot according to an exemplary embodiment of this disclosure, among other possible things includes applying a coating to a slot in a component and machining the coating to provide an open width configured to receive a seal. after the applying, the slot has an initial open width that is smaller than the open width after the machining. A method of forming a sealing assembly is also disclosed.

Abstract: A system for chemical vapor deposition coating of fiber tows includes a coater having a housing having a tow entrance and a tow exit and defining an interior space, the coater further having a process gas inlet and a process gas outlet; at least one of an entrance side marker gas inlet at the tow entrance and an exit side marker gas inlet at the tow exit; and at least one of an entrance side detection probe upstream of the entrance side marker gas inlet, and an exit side detection probe downstream of the exit side marker gas inlet, the at least one entrance side detection probe and exit side detection probe being configured to detect marker gas. A method is also disclosed.

Abstract: A method of manufacturing a heat exchanger core from glass ceramic matrix composite includes placing one or more reinforcing fibers around one or more mandrels into a mold cavity. A glass matrix material infiltrates the one or more reinforcing fibers to produce an infiltrated core and the one or more mandrels is removed to create one or more passages passing through the infiltrated core.

Abstract: A method for coating a fiber tow includes moving a fiber tow across a wedge to separate the fiber tow into a plurality of sub-tows, and coating the plurality of sub-tows.

Abstract: A tow coating reactor system includes a reactor for receiving fiber tow, a wedge situated adjacent the reactor and configured to receive the tow at a tip end, such that as the tow moves across the wedge, the wedge spreads the tow into a plurality of sub-tows.

Abstract: A method of spreading fiber tows includes assembling a fibrous composite from a plurality of tows, applying an aqueous solution to the fibrous composite, freezing the fibrous composite after applying the aqueous solution, freeze drying the fibrous composite to remove water from the fibrous composite, and heating the fibrous composite after freeze drying to remove a cryoprotectant from the fibrous composite. The aqueous solution comprises water and the cryoprotectant and freezing the fibrous composite spreads filaments within the plurality of fiber tows.

Abstract: A method of spreading fiber tows includes applying a coupling medium to a surface of a fibrous structure, positioning an ultrasonic probe adjacent to the surface of a fibrous structure, such that a tip of the ultrasonic probe is in contact with the coupling medium, moving at least one of the ultrasonic probe and the fabric structure relative to the other of the ultrasonic probe and the fibrous structure according to a first pattern, and imparting ultrasonic vibration with the ultrasonic probe to the surface of the fibrous structure while moving the ultrasonic probe along the surface of the fibrous structure. Imparting ultrasonic vibration to the surface of the fibrous structure spreads tows of the fibrous structure.