A three-dimensional fibrous preform of a fan blade includes a blade root and a blade airfoil between the blade root and a free end of the preform. The airfoil has an area with two skins and a longitudinal stiffener between the skins and, in a transverse plane, transverse yarns of the skins woven in pairs in the first and in the second skin either side of the stiffener, the yarns of a first pair of the first skin are separated into two unit yarns at the stiffener, the unit yarns being woven separately with longitudinal yarns, the yarns of a second pair of the second skin are separated into two unit yarns at the stiffener, the yarns being woven separately with longitudinal yarns, and a yarn of each pair cross over each other twice in the stiffener.

Disclosed herein are articles comprising: (a) a glass micro sheet having top and bottom surfaces and a thickness of about 0.001 to about 0.040 inches; and (b) a layer comprising a plurality of composite layers, the layer having top and bottom surfaces, wherein the bottom layer of the glass micro sheet is bonded to the top surface of the layer comprising a plurality of composite layers; and wherein the (Ra) of the top surface of the glass micro sheet is 1 nm<Ra<1 μm, and methods of making same.

The assembly (24) comprises: a woven first fabric (26) comprising filamentary warp elements (64) comprising first and second filamentary members, a woven second fabric (28), a bearing structure (30) comprising filamentary bearing elements (32) connecting the woven first and second fabrics together. For a length at rest L of the woven first fabric (26): for any elongation of the woven first fabric (26) less than or equal to (2π×H)/L, the first filamentary member has a non-zero elongation and is not broken; there is an elongation of the woven first fabric (26), less than or equal to (2π×H)/L, and beyond which the second filamentary member is broken, in which H0×K≤H where H0 is the distance between the woven first and second fabrics (26, 28) when each filamentary bearing portion (74) is at rest, and K=0.50.

A ballistic-resistant articles, and methods for their preparation, based on sheets of UHMWPE films with discontinuous film splits, which combine flexibility and good ballistic properties, making them suitable for both soft-ballistic and hard-ballistic applications.

There is disclosed a method of providing through-thickness reinforcement in a laminated material. A guide foot is moved to a datum location relative the laminated material, at which the guide foot abuts a reinforcement zone on a surface of the laminated material. An insertion operation is conducted by inserting an insertion element through the guide foot into the laminated material along an insertion direction when the guide foot is in the datum location. The insertion element comprises a needle for forming a hole in the laminated material; a reinforcement rod to be received in the laminated material; or a tamping pin for tamping a reinforcement rod received in the laminated material. A corresponding insertion apparatus is disclosed.

There is disclosed a method of providing through-thickness reinforcement in a laminated material. A guide foot is moved to a datum location relative the laminated material, at which the guide foot abuts a reinforcement zone on a surface of the laminated material. An insertion operation is conducted by inserting an insertion element through the guide foot into the laminated material along an insertion direction when the guide foot is in the datum location. The insertion element comprises a needle for forming a hole in the laminated material; a reinforcement rod to be received in the laminated material; or a tamping pin for tamping a reinforcement rod received in the laminated material. A corresponding insertion apparatus is disclosed.

A gas turbine component made of composite material includes a fiber reinforcement having a three-dimensional weave between a plurality of warp threads and a plurality of weft threads, the fiber reinforcement being densified by a matrix. The densified fiber reinforcement extends in width between a downstream end and an upstream end in an axial direction and in thickness between an inner surface and an outer surface in a radial direction. The fiber reinforcement densified by the matrix has a hollowed-out portion extending through the entire thickness of the fiber reinforcement. A composite material filler piece is present in the free volume of the component delimited by the hollowed-out portion, the filler piece including a fiber preform having a three-dimensional weave, the fiber preform being densified by a matrix.

A method for repairing a part made of composite material includes producing a recessed section by removing the composite material at a damaged area, producing grooves extending on the two faces of the part from edges of the recessed section, producing orifices in the part opening out into the grooves, tree-dimensional weaving of a filling part fiber preforms including a central section having a shape corresponding to the shape of the recessed section and fiber bundles extending from the central section, placing the filling preforms respectively on either face of the part with the fiber bundles in the grooves on the faces of the part and in the orifices such that the fiber bundles open out into the grooves present on the opposite face of the part, impregnating the filling fiber preforms with a precursor resin of a matrix, transforming the resin into a matrix to obtain a filling part.

A method for repairing a part made of composite material includes producing a recessed section by removing the composite material at a damaged area, producing grooves extending on the two faces of the part from edges of the recessed section, producing orifices in the part opening out into the grooves, tree-dimensional weaving of a filling part fiber preforms including a central section having a shape corresponding to the shape of the recessed section and fiber bundles extending from the central section, placing the filling preforms respectively on either face of the part with the fiber bundles in the grooves on the faces of the part and in the orifices such that the fiber bundles open out into the grooves present on the opposite face of the part, impregnating the filling fiber preforms with a precursor resin of a matrix, transforming the resin into a matrix to obtain a filling part.

A stitched multi-axial reinforcement and a method of producing a stitched multi-axial reinforcement. The stitched multi-axial reinforcement (40) may be used in applications where high quality and strength is required. The stitched multi-axial reinforcement includes at least two sets of mono- or bonded multifilaments arranged transverse to one another between reinforcing layers for ensuring good resin flow properties in directions transverse to the direction of the unidirectional rovings (20′, 32′).