System includes a first object having an energy-assisted bonding (EAB) mechanism along a surface of the first object. The EAB mechanism includes a heat-activatable adhesive layer and a carbon-filled (CF) sheet material. The CF sheet material is electrically conductive for resistive heating. A control sub-system is configured to control a coupling actuator to drive an actuator body toward the first object, wherein the actuator body and the first object engage each other. The coupling actuator is configured to apply pressure to the EAB mechanism along the surface of the first object. The control sub-system is also configured to control the power source to apply a current through the CF sheet material of the EAB mechanism to provide thermal energy through resistive heating that activates the adhesive layer along the interface.

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.

A method for joining a device to an object with the aid of a combination of ultrasonic vibration energy and induction heating, wherein the device includes a portion of a thermoplastic polymer and a susceptor additive wherein this portion is at least partly liquefied or plasticized through the ultrasonic vibration energy in combination with the induction heating and wherein the joining includes establishing a connection between the device and the object which connection is at least one of a positive fit connection, a weld, a press fit connection, and an adhesive connection. The induction heating is applied for rendering the device portion suitable for absorption of ultrasonic vibration energy than other device portions by raising its temperature above the glass transition temperature of the polymer. The ultrasonic vibration energy is used for liquefying or at least plasticizing the thermoplastic polymer of the named device portion.

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.

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 installation for welding a stack of parts made of thermoplastic composite materials (20) in a local welding plane (P), this installation including an electromagnetic induction head (8), pairs of elements for guiding and pressing the workpiece stack (20) in this local plane (P), and, on each side of the induction head (8), at least one pair of guide elements, each pair of guide elements having a lower guide element (14) and an upper guide element (10) that are superposed, receiving between one another the stack of parts (20) by guiding it in the direction perpendicular to the local welding plane (P).

System includes a first object having an energy-assisted bonding (EAB) mechanism along a surface of the first object. The EAB mechanism includes a heat-activatable adhesive layer and a carbon-filled (CF) sheet material. The CF sheet material is electrically conductive for resistive heating. A control sub-system is configured to control a coupling actuator to drive an actuator body toward the first object, wherein the actuator body and the first object engage each other. The coupling actuator is configured to apply pressure to the EAB mechanism along the surface of the first object. The control sub-system is also configured to control the power source to apply a current through the CF sheet material of the EAB mechanism to provide thermal energy through resistive heating that activates the adhesive layer along the interface.

A joining method for thermoplastic elements that comprises the steps of providing two thermoplastic parts having two surfaces to be joined, locating a graphene layer between the two thermoplastic parts adjacent to the surfaces to be joined, and heating the graphene layer such that the graphene layer melts the thermoplastic resin of the adjacent surfaces of the two thermoplastic parts that are to be joined.

A method for joining a device to an object with the aid of a combination of ultrasonic vibration energy and induction heating, wherein the device includes a portion of a thermoplastic polymer and a susceptor additive wherein this portion is at least partly liquefied or plasticized through the ultrasonic vibration energy in combination with the induction heating and wherein the joining includes establishing a connection between the device and the object which connection is at least one of a positive fit connection, a weld, a press fit connection, and an adhesive connection. The induction heating is applied for rendering the device portion suitable for absorption of ultrasonic vibration energy than other device portions by raising its temperature above the glass transition temperature of the polymer. The ultrasonic vibration energy is used for liquefying or at least plasticizing the thermoplastic polymer of the named device portion.

The disclosure relates to reversible bonded structural joints using active adhesive compositions that can allow for dis-assembly, repair, and re-assembly. The disclosure is particularly directed to the adhesive composition material, irrespective of the type of the substrate(s) being joined. The adhesive composition can include any thermoplastic adhesive material that can be remotely activated for targeted heating of just the adhesive composition (e.g., and not the surrounding substrates being joined) via the inclusion of electromagnetically excitable particles in the adhesive composition. The substrates can be any metal material, any composite material, any hybrid material, or otherwise. The disclosed adhesive compositions allow for recyclability of parts at the end of their lifetime and repair/replacement of parts during their lifetime.