Systems and methods are provided for fabricating a hybrid composite part. A method includes braiding a first set of fibers to form a weave having a closed cross-sectional shape, braiding a second set of fibers into the weave that are chemically distinct from the first set of fibers, impregnating the weave with a resin, and hardening the resin within the weave to form a hybrid composite part.

A fiber-orientation system for a fiber-reinforced thermoplastic is provided. In various embodiments, the system includes a first tool, and a second tool that, in combination with the first tool, defines a gap therebetween configured to define a flow path for a fiber-reinforced thermoplastic melt during an injection molding. A plurality of electrodes are disposed in the first tool. The electrodes have exposed ends disposed in or along the flow path such that the electrodes are configured to, when energized, orient fibers within the thermoplastic melt. This provides a localized, controllable modification of the orientation of the fibers within the melt.

A composite fibrous susceptor for use in induction welding is described, along with methods of its construction and use. The composite fibrous susceptor can include a magnetically susceptible continuous fiber in conjunction with a thermoplastic polymer. The composite fibrous susceptor can be deposited according to an additive manufacturing process on a surface to be bonded according to an induction welding process.

A composite fibrous susceptor for use in induction welding is described, along with methods of its construction and use. The composite fibrous susceptor can include a magnetically susceptible continuous fiber in conjunction with a thermoplastic polymer. The composite fibrous susceptor can be deposited according to an additive manufacturing process on a surface to be bonded according to an induction welding process.

A method for simple and economical positioning of two work pieces with one another wherein the pieces are welded using induction heating to melt a polymer in a composite wherein air can be blown on the surface to limit the welding to an area close to the mating surface of the work pieces and to prevent melting of the outer surface which would deteriorate the quality of the outer surface.

A heating element for resistance welding of thermoplastic components for aircraft comprises electrically conductive elements in the form of wires or fibers, which heat up upon application of an electric voltage to the heating element, to weld a first component to a second component in a region electrically heated by the heating element. The electrically conductive elements extend parallel to one another between contact regions for electrically contacting the heating element. After the welding procedure, the heating element remains between the welded components to enhance the strength of the welded bond. A device for bonding thermoplastic components by resistance welding comprises the heating element and a unit in the form of roller electrodes for displacing an electrically heated region of the components in the welding direction. The electrically conductive elements extend parallel to the axis of rotation of the roller electrodes.

An in-situ fiber-optic temperature field measurement is disclosed that can allow process monitoring and diagnosis for thermoplastic composite welding and other applications. A distributed fiber-optic sensor can be permanently embedded in a thermoplastic welded structure when it is welded and left there to perform lifelong monitoring and inspection. The fiber optic sensor can include a dissolvable coating, or a coating matched to the composite material to be welded. Other applications include in-situ fiber-optic temperature field measurement on thermoset composite curing (autoclave), for thermoplastic and thermoset composites during compression molding, and for fiber-optic field measurements on freeze/thaw of large items of public health interest, such as stored or transported foodstuffs.

An end effector for welding composite components includes an end effector housing and a welding member mounted to the end effector housing. The end effector further includes a leading roller mounted to the end effector housing forward of the welding member and at least one follower roller mounted to the end effector housing aft of the welding member. The end effector further includes at least one first cooling air jet positioned to direct a first stream of cooling air toward the at least one follower roller.

A method for assembling by welding at least two components of composite material includes positioning at least one connection layer of fibers so as to be interposed between the contact surfaces of the two components and/or positioned in the region of at least one contact surface of the two components, each connection layer having unidirectional fibers which are oriented in a direction different from the directions of the fibers of at least the fiber layers of the two components close to the contact surfaces. An induced electrical current is generated in a direction approximately parallel with the direction of the fibers of each connection layer. This method enables heating to be concentrated in the region of the contact surfaces. An assembly is disclosed of at least two components of composite material by carrying out the method.

A fuselage structure of an aircraft includes a fuselage skin, and a plurality of frame elements spaced apart from one another in a direction parallel to the aircraft longitudinal axis for supporting the fuselage skin. The fuselage skin includes a plurality of interconnected fiber-reinforced composite skin panels that extend between each pair of frame elements and are connected thereto. The composite skin panels further comprise a stiffener integrally formed in each composite skin panel. A method for manufacturing the fuselage skin. The composite skin panels may be interconnected and/or connected to a frame element through an induction welded connection.