Composite joints and methods of forming composite joints are presented. A composite joint comprising: a first composite component formed of one of a thermoset material or a first thermoplastic material; a second composite component formed of a thermoset material or a third thermoplastic material; a thermoplastic joining film formed of a second thermoplastic material between the first composite component and the second composite component, the second thermoplastic material different from the thermoset material, first thermoplastic material, and third thermoplastic material; and a carbon conductive layer in the thermoplastic joining film.

A method and apparatus for welding a thermoplastic structure. The apparatus comprises a base, a cover, and a channel. The base is formed of a material that is magnetically opaque to a frequency in a range of 30 KHz to 350 KHz. The cover is formed of the material. The channel extends between the base and the cover.

A process for laminating a material layer to a support including: providing the support, applying the material layer to the support, a heat-activatable adhesive being applied to s side of the material layer facing the dimensionally stable support and/or to the side of the dimensionally stable support facing the material layer, pressing the flexible material layer and the dimensionally stable support together by means of a lower dimensionally stable mold half and an upper dimensionally stable mold half, irradiating the mold halves, the support and the material layer with electromagnetic radiation, in particular with microwave radiation, high-frequency radiation or induction radiation, whereby the adhesive is activated directly or indirectly.

A method of connecting surfaces of first and second molded parts by electromagnetic welding. The first molded part includes a first lightning strike protection (LSP) material at an outer surface thereof. The method includes providing the first and second molded parts to comprise a heat meltable coupling and an induction-sensitive component; bringing together the surfaces to be connected and pressurizing the surfaces by providing a pressurizing body against the molded parts; generating an electromagnetic field in the surfaces to be connected of the molded parts by means of an inductor, thereby heat melting the coupling means by heating the induction-sensitive component; cooling the outer surface of the first molded part by providing a heat sink in contact with the outer surface; and coupling the molded parts under pressure by the molten heat meltable coupling means. A second lightning strike protection (LSP) material is provided at the surfaces to be connected.

Provided is an electric power control apparatus of an electrofusion coupling pipe using a conductive polymer composite as a heating element and a method of controlling electric power using the same. The electric power control apparatus supplies electric power to the electrofusion coupling pipe using a conductive polymer composite as a heating element to detect resistance variation of the conductive polymer composite and then controls electric power supplied to the synthetic resin pipe electrofusion coupling pipe on the basis of the detected resistance variation.

Described herein are thermoplastic composites and methods of making thereof. The thermoplastic composites disclosed herein can include at least one randomly-oriented carbon fiber layer in the laminate to improve induction heating efficiency of the thermoplastic composite.

A heatsink, a method of manufacturing the heatsink, and an induction welding apparatus including the heatsink. The heatsink includes a carrier sheet and a plurality of tiles. The carrier sheet comprises an electrically non-conductive material and has a contoured profile. The plurality of tiles comprises a thermally conductive and electrically non-conductive material. Each tile of the plurality of tiles has a bonding surface bonded to the carrier sheet and a contact surface opposite the bonding surface. The contact surface is configured to contact a structure to be induction welded.

An induction welding coil includes a spine having a planar body with opposing ends, and a pair of prongs extending perpendicularly from the opposing ends of the spine. Each of the prongs has a planar body, wherein the spine and the pair of prongs are formed from a ferrite material to define a ferrite core. The induction welding coil further includes a coil wire having a plurality of winding that surround the planar body of the spine.

A composite structure and methods of forming composite structures are provided. A composite structure comprises a first composite part; a second composite part welded to the first composite part at a joint; and the joint between the first composite part and the second composite part comprising doped fibers.

A heat sink for use in electromagnetic welding of molded parts includes reinforcing fibers embedded in a matrix material, where substantially all of the reinforcing fibers are oriented unidirectionally in a fiber direction, where the reinforcing fibers have a thermal conductivity at room temperature from 100-1000 W/m. K and an electrical resistivity at room temperature from 0.5-10.m, and where the matrix material comprises a high temperature resistant material, optionally a thermosetting resin, having a glass transition temperature Tg above 350 C. The heat sink is used in a method of connecting surfaces of a first molded part and a second molded part by electromagnetic welding. Cooling of the outer surface of the first molded part is provided by the heat sink in direct contact with the outer surface.