A method of making a fiber preform, and the preform, for fabricating a turbine engine blade out of composite material, the method including: making a single-piece fiber blank by three-dimensional weaving with layers of longitudinal yarns interlinked by yarns of layers of transverse yarns; and shaping the fiber blank to obtain a single-piece fiber preform including a portion forming an airfoil preform and at least one portion forming a platform preform. During weaving, yarns of a first group of longitudinal yarns are extracted from the fiber blank beside one of side faces of the blank to form a portion corresponding to a blade platform preform, and yarns of a second group of longitudinal yarns are inserted into the fiber blank with mutual crossing of the yarns of the first group and the yarns of the second group.

A centrifugal impeller for a turbomachine is provided. The centrifugal impeller comprises a plurality of aerodynamic vanes, each of the aerodynamic vanes having internal walls on which is associated a fabric element.

Methods for manufacturing a turbomachine composite part, such as a fan blade, are provided. The composite part has a fibrous structure with a three-dimensional fibrous preform coated with a surface fibrous web, and which is embedded in a polymer matrix The methods include: forming the surface web in a cavity of a mold in order to shape it, wetting and forming the preform on the surface web in order to shape it, and closing the mold, drying the fibrous structure, and injecting thermosetting resin into the mold in order to form said polymer matrix. The surface web is wetted before and/or during the forming thereof.

In a fiber structure woven as a single piece by three-dimensional weaving, first warp yarns interlink layers of weft yarns in a first portion of the fiber structure adjacent to a non-interlinked zone and also weft yarns of a second portion of the fiber structure beyond the non-interlinked zone, and second warp yarns interlink layers of weft yarns of the second portion of the fiber structure adjacent to the non-interlinked zone and also layers of weft yarns of the first portion of the fiber structure beyond the non-interlinked zone, such that the paths of the first and second warp yarns cross in at least one transition zone extending within the fiber structure from the end of the non-interlinked zone, the transition zone extending in the warp direction over a distance greater than the pitch between adjacent warp columns.

Provided is a vacuum pump in which no finish processing has to be carried out after shaping of a cylindrical rotor even in use of a cylindrical rotor obtained by shaping a fiber-reinforced plastic material into a cylindrical shape. The vacuum pump has a turbo-molecular pump section and a thread groove pump section. The upper end section of a cylindrical rotor, which is obtained by shaping a fiber-reinforced plastic material into a cylindrical shape, of the thread groove pump section, is joined to the lower end section of a rotor of the turbo-molecular pump section. A joining portion of the rotor of the turbo-molecular pump section and the cylindrical rotor of the thread groove pump section is disposed upstream of an exhaust passage. As a result, finish processing does not have to be carried out after shaping of the cylindrical rotor. If finish processing is performed after shaping of the cylindrical rotor a resin may be coated onto a rugged portion of the cylindrical rotor, or fibers may be helically wound at a winding angle not greater than 45 degrees.

A ceramic matrix composite seal is disclosed. The ceramic matrix composite seal including a ceramic matrix and a number of ceramic fiber fabrics embedded in the ceramic matrix. The ceramic matrix composite seal is formed into a strip with a desired geometry such that the seal strip is configured to be assembled with a number of components to create a seal between the components.

A fan track liner for a fan containment arrangement for a gas turbine includes a cellular impact structure and a supporting sub-laminate integrally formed with each other from fibre-reinforced material. The fan track liner further includes a ballistic barrier comprising a woven reinforcing fibre ply and a layer of reinforcing fibre felt. There is also disclosed an associated fan containment arrangement and a method of manufacturing a fan track liner.

An airfoil includes an airfoil wall that defines a leading end, a trailing end, and pressure and suction sides that join the leading end and the trailing end. The airfoil wall includes a wishbone-shaped fiber layer structure that has a pair of arms that merge into a single leg. The pair of arms are formed by first and second S-shaped fiber layers each of which is comprised of a network of fiber tows. The first and second S-shaped fiber layers merge to form the single leg. The single leg comprises fiber tows from each of the first and second S-shaped fiber layers that are interwoven, and the single leg forms at least a portion of the trailing end of the airfoil wall.

A multi-layer braided article and a method of making the multi-layer braided article. The multi-layer braided article includes a braid extending along a first axis, wherein the braid is folded over itself to form a first layer and a second layer; and a wrapper laid over the first layer of the braid and extending circumferentially around the first axis, wherein the wrapper defines an edge of the first layer about which the braid is folded. The multi-layer braided article may form part of a blade for an aircraft. A sleeve may be provided around a conical portion of the article to connect the article to something else, such as a propeller hub, where the multi-layer braided article is formed as part of a blade. The sleeve may provide a primary or secondary load path.

The disclosure describes composite liners (such as acoustic panels, fan track liners, and/or ice impact panels or boxes for turbofan engines) and techniques for forming composite liners. In some examples, the composite liner includes at least one region comprising a reinforcement architecture comprising a matrix material, a plurality of relatively tough polymer-based reinforcement elements, and a plurality of second reinforcement elements. The plurality of relatively tough polymer-based reinforcement elements and the plurality of second reinforcement elements are embedded in the matrix material.