A method for integrating a fitting (110) fitted between two wings of a composite profile (100) comprising the steps of: i) obtaining a preform of a fitting impregnated with a thermosetting resin, comprising two flanges (111) and a rib (114); ii) pre-curing the laminate preform of the fitting to obtain a partial polymerization of the preform; iii) laying up a laminate preform of the profile so that fibers impregnated with a thermosetting resin included in two of the wings of the laminate preform of the profile are laid up over the two flanges of the preform of the partially polymerized fitting; and iv) completely polymerizing an assembly comprising the laminate preform of the profile and the laminate preform of the partially polymerized fitting while maintaining into contact the flanges of the laminate preform of the fitting with the wings of the laminate preform of the profile.

The invention also pertains to a tooling for implementing the method and a wing spar obtained by this method.

A method for bonding composite structures which includes providing a first and second composite substrate and coupling a co-cure prepreg tape having chemically protected polymerizable functional groups onto a surface of both the first and second composite substrates. The first and second composite substrates are then cured to the co-cure prepreg tape at a first temperature to form a co-cure prepreg tape portion where the first and second composite substrates are fully cured and the co-cure prepreg tape is partially cured. The co-cure prepreg tape portion of the first composite substrate is then coupled to the co-cure prepreg tape portion of the second composite substrate and a deprotection initiator is applied to facilitate deprotection of the chemically protected polymerizable functional groups and cure the co-cure prepreg tape portion of the first and second composite substrates to form a single covalently bonded composite structure.

Process for forming a permanent join between two sections of fibrous material contained in a thermosetting resin matrix, said process comprising overlaying the two sections and subjecting the overlaid sections to ultrasonic welding to form a permanent join between the two sections, wherein there is no significant change in the sub-ambient Tg of the fibrous material contained in the thermosetting resin matrix in the region of the permanent join.

An apparatus and a method for stitching are provided. The apparatus includes a separator for separating in a separation position the leading end and the trailing end from a working surface to form a separation space, a stitcher unit with a stitcher foot to support the leading end and the trailing end from the separation space and a stitcher head for stitching the leading end and the trailing end on the stitcher foot from outside the separation space, a stitcher drive for driving the stitcher unit, a separator drive for retracting the separator, and a control unit to control the separator drive and the stitcher drive simultaneously such that, during the stitching, the separator is retracted in the stitching direction ahead of the stitcher unit.

A method for joining structural elements to a component made of at least one fiber-reinforced plastics material, includes providing at least two structural elements made of at least one fiber-reinforced plastics material having a particular matrix; providing at least one film element made of a thermoplastic heavy-duty material; arranging the at least one film element on a surface of one of the structural elements or between surfaces to be joined of the at least two structural elements to be joined; and producing the component to be joined in a curing process.

A hollow tube assembly is constructed from two or more concave segments, each having longitudinal edges that are tapered perpendicular to the longitudinal direction of the assembly with substantially identical tapers. The respective tapered edges are joined at respective joining faces forming scarf joints, either with or without applying an adhesive between opposing joining faces. The overall thickness of the scarf joint may substantially correspond to the thickness of the segments. The scarf joints may be straight or arcuate. The segments may be constructed by overlaying layers of a composite material made of carbon fiber reinforced polymers and may be provided in pre-impregnated (prepreg) form.

Composite laminate structures are produced using partially cured parts. Partial curing of the parts is achieved by applying a catalyst to regions of the parts that are to be fully cured. These regions cure at a lower-than-normal temperature while remaining regions of the part remain uncured, allowing them to be co-bonded or co-cured to other structures.

Provided is a method for forming a co-cured composite article. The method includes: providing a bag carrier; providing a vacuum bag, wherein the vacuum bag at least partially surrounds the bag carrier; providing an outer skin, wherein the outer skin at least partially surrounds the vacuum bag; forming a space between the bag carrier and the the outer skin; and providing a filler between the outer skin and the bag carrier.

An open-channel stiffener for stiffening a panel has a bonding flange for bonding the stiffener to the panel through a bondline formed between the bonding flange and the panel to form a stiffened panel. The open-channel stiffener has a cross-sectional shape that aligns, or substantially aligns, a shear center of the stiffener with a centroid of the stiffener and aligns the shear center proximate an edge of the bondline, and removes the need for a radius filler noodle. A plurality of perforations may be formed through the bonding flange to permit an adhesive to wick into the perforations and create a mechanical interlock between the bonding flange and the panel.

A method and an apparatus for welding a first object to a second object, wherein the first object is produced from a thermoset and comprises a thermoplastic material outer layer, wherein the second object comprises at least one thermoplastic material outer layer. In addition, a layer of carbon nanotubes is applied to the thermoplastic material outer layer of the first object, and the second object is placed onto the first object. At least some of the thermoplastic material outer layer of the second object lies atop the applied layer of carbon nanotubes. In addition, a potential is applied to the layer of carbon nanotubes, such that an electrical current flows through the carbon nanotubes, wherein the thermoplastic material outer layer of the first object and the thermoplastic material outer layer of the second object are heated and are welded to one another.