A method of assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, positioning an array of airfoils about an outer periphery of a hub, the hub being rotatable about an engine longitudinal axis of a gas turbine engine, the hub including a plurality of flanges, and each one of the airfoils including an airfoil section extending from a root section. An array of platforms are positioned about the outer periphery of the hub, each of the platforms including one or more slots defined by a plurality of platform flanges, and including the one or more slots receiving a respective one of the flanges of the hub. A plurality of retention pins are moved relative to the array of airfoils such each one of the retention pins extends through the flanges of the hub and through the plurality of platform flanges of a respective one of the platforms to mechanically attach a respective one of the platforms and the root section of a respective one of the airfoils to the hub. At least one of the airfoils and the platforms includes a plurality of composite layers that define an internal cavity, and includes a lattice structure in the internal cavity that extends between the plurality of composite layers.

A method for manufacturing a blade made of composite material for a turbine engine, in particular of an aircraft, the steps of injecting a resin in order to impregnate a fibrous preform woven in three dimensions and polymerizing the resin so as to form the blade that includes an airfoil, one longitudinal end of which is connected to a platform. The platform includes pressure and suction portions connected to the airfoil by a fillet, wherein a separation is formed in the fibrous preform between the pressure and suction portions. The method further includes reinforcing a leading edge of the airfoil; and reinforcing the fillets by integration of a metal reinforcement on at least one part of the pressure and suction portions of the platform and in the separation.

An assembly for a gas turbine engine includes an airfoil that includes an airfoil section that extends from a root section. The airfoil section extends between a leading edge and a trailing edge in a chordwise direction and extends between a tip portion and the root section in a radial direction. The airfoil section defines a pressure side and a suction side separated in a thickness direction. A platform is dimensioned to receive a retention pin to mount the platform to a rotatable hub. The platform includes a plurality of composite layers that define an internal cavity. A filler includes a stacked composite structure in the internal cavity that extends between the plurality of composite layers.

An airfoil includes a ceramic matrix composite airfoil core that defines an airfoil portion and a root portion. The ceramic matrix composite airfoil core is subject to core thermal growth. A platform includes a ceramic matrix composite that wraps around the root portion. The platform is subject to platform thermal growth. A buffer layer is located between the root portion and the platform. The buffer layer absorbs a mismatch between the core thermal growth and the platform thermal growth.

An airfoil includes a ceramic matrix composite airfoil core that defines an airfoil portion and a root portion. The ceramic matrix composite airfoil core is subject to core thermal growth. A platform includes a ceramic matrix composite that wraps around the root portion. The platform is subject to platform thermal growth. A buffer layer is located between the root portion and the platform. The buffer layer absorbs a mismatch between the core thermal growth and the platform thermal growth.

A protective coating composition for providing protection to a component of a ram air turbine system in need thereof. The protective coating composition comprises an aqueous-soluble or alkaline-soluble polymer matrix, one or more compressible fillers, and one or more non-compressible fillers. The disclosure also provides a method for providing a protective coating onto components of a ram air turbine system in need thereof for providing indentation and scratch resistance thereto.

A method of assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, positioning an array of airfoils about an outer periphery of a hub, the hub being rotatable about an engine longitudinal axis of a gas turbine engine, the hub including a plurality of flanges, and each one of the airfoils including an airfoil section extending from a root section. An array of platforms are positioned about the outer periphery of the hub, each of the platforms including one or more slots defined by a plurality of platform flanges, and including the one or more slots receiving a respective one of the flanges of the hub. A plurality of retention pins are moved relative to the array of airfoils such each one of the retention pins extends through the flanges of the hub and through the plurality of platform flanges of a respective one of the platforms to mechanically attach a respective one of the platforms and the root section of a respective one of the airfoils to the hub. At least one of the airfoils and the platforms includes a plurality of composite layers that define an internal cavity, and includes a lattice structure in the internal cavity that extends between the plurality of composite layers.

An assembly includes a first part and a second part separate from the first part, the first and second parts being intended to be in frictional contact, the first part being made of an organic matrix composite material that has, on its surface, an abrasion-resistant area including a resin that contains polytetrafluoroethylene particles, the polytetrafluoroethylene particles being only present at the surface of the first part, and the second part being made of an organic matrix composite material and being in contact with the abrasion-resistant area of the first part.

A method of manufacturing an article having a first component that mates with a second component is provided. The method includes: producing a first component having a first mating feature; measuring the dimensions of the first mating feature and creating a profile representative of the measured dimensions; and producing a second component having a second mating feature that mates with the first mating feature, wherein the second mating feature is produced using the profile.

An assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, an airfoil that has an airfoil section extending from a root section. The airfoil section extends between a leading edge and a trailing edge in a chordwise direction and extending between a tip portion and the root section in a radial direction. The airfoil section defines a pressure side and a suction side separated in a thickness direction. A platform is dimensioned to receive a retention pin to mount the platform to a rotatable hub. At least one of the airfoil and the platform includes a plurality of composite layers that define an internal cavity. A lattice structure in the internal cavity extends between the plurality of composite layers. The lattice structure has a plurality of branches that extend from a plurality of nodes.