The invention relates to the use of a low Tg compatible resin as an adhesive layer for the welding of a thermoplastic composite structure to a thermoplastic or thermoset structure. The invention is especially good for the welding of large parts, such as wind turbine halves and spar caps. A useful thermoplastic composite is one formed by the infusion and curing of long fibers by a reactive acrylic liquid resin system, such as ELIUM® resin systems from Arkema.

A bonded composite joint includes a first carbon fiber-reinforced polymer (CFRP) panel; a second CFRP panel; a corrugated structure placed between the first and second CFRP panels; and an adhesive placed between the first and second CFRP panels and in contact with the corrugated structure. The corrugated structure has a shape defined by a given wavelength λ.

A CFRP material with an Al alloy sheet attached to or a CFRTP material with an Al alloy sheet attached to is prepared by joining an Al alloy sheet with a CFRP material or a CFRTP material by adhesion or by injection molding. The surface of this Al alloy sheet and a surface of metal material such as Ti, etc., are subjected to chemical treatment. After this chemical treatment, the CFRP material with an Al alloy sheet attached to or the CFRTP material with an Al alloy sheet attached to and the metal material are inserted into a metallic mold for injection molding so as to have a gap therebetween. High crystalline thermoplastic resin is injected into this gap to join the metal material with the Al alloy sheet, thus obtaining a laminated composite.

A system for holding a workpiece in position and exposing it to laser radiation, such that: the workpiece includes a bottom surface and a top surface that are electrically insulated from each other. The system includes an electrostatic charge generating device for generating electrostatic charges on the top surface; an electrically conductive support for forming, on the bottom surface, electrostatic charges of opposite sign to those generated on the top surface; and a laser device for machining or welding. The electrostatic charge generating device is arranged to be activated before or during the laser machining or welding, such that the workpiece is held in position relative to the electrically conductive support during the machining or welding thereof.

A joined article includes a first component having a laser-treated surface portion and a second component having a laser-treated surface portion. An adhesive joins the first component to the second component at the treated surface portion. A method of making a joined article form components and a system for making joined articles are also disclosed.

A welder for joining two polymeric sheets together using a wedged heating element allows for a heating profile on opposite faces of the heating element to be varied by controlling where each of the polymeric sheets contacts the corresponding face.

Riveted assemblies are provided that can include a substrate extending between two ends to define opposing substrate surfaces having a first opening extending between the opposing substrate surfaces; a metal-comprising substrate extending between two ends to define opposing metal-comprising substrate surfaces having a second opening extending between the opposing metal-comprising substrate surfaces. The riveted assemblies can further provide that the first and second openings complement one another when the substrate and metal-comprising substrate are engaged; and a rivet shaft extends through the openings and engages the substrate with the rivet head and the metal-comprising substrate with the rivet stop head, at least a portion of the stop head being mixed with, and forming a metallurgical bond with the metal-comprising substrate. Assemblies are provided that can include a rivet stop head mixed with, and metallurgically bonded with a metal-comprising substrate.

Methods for affixing substrates to one another are also provided. The methods can include providing a substrate defining an opening configured to receive a rivet shaft; providing a metal-comprising substrate defining a complimentary opening; operatively engaging the substrates with the rivet shaft; and forming a stop head from the rivet shaft to affix the substrates. The method further includes that the stop head mixes with, and forms a metallurgical bond with the metal-comprising substrate. Methods for mixing materials to form a metallurgical bond are also provided. The methods can include forming a metallurgical bond between a stop head of a rivet and a metal-comprising substrate.

A method for optimizing a welding process to produce a weld joint having a predetermined strength includes measuring a plurality of melt layer thicknesses of weld joints for a plurality of sample assemblies formed by the welding process, measuring a plurality failure loads of weld joints for the plurality of sample assemblies, each of the measured plurality of failures loads being associated with one of the measured plurality of melt layer thicknesses, selecting a first failure load from the plurality of measured failure loads responsive to determining that the first failure load corresponds to a predetermined weld strength, and selecting a first melt layer thickness from the plurality of measured melt layer thicknesses that is associated with the selected first measured failure load.

A method for manufacturing a composite member, in which a composite member having a high joining strength can be manufactured in an inexpensive and efficient way; and the composite member. A metal member and a resin-containing member are joined together by heating the metal member while pressing the resin-containing member against a metal porous film formed on a surface of the metal member. The porous film is formed by impacting the surface of the metal member with metal powder by the cold spray process.

A high-frequency dielectric heating adhesive contains a thermoplastic resin, in which the thermoplastic resin contains a styrene copolymer resin, an amount of the styrene copolymer resin contained in the thermoplastic resin is 40% or more by volume and 100% or less by volume, the styrene copolymer resin has a styrene monomer unit content of 10% or more by mass and 90% or less by mass, the high-frequency dielectric heating adhesive has a tensile modulus of 20 MPa or more, and the high-frequency dielectric heating adhesive has a dielectric property (tan δ/ε'r) of 0.005 or more, where tan δ is a dielectric loss tangent at 23° C. and a frequency of 40.68 MHz, and ε'r is a relative dielectric constant at 23° C. and a frequency of 40.68 MHz.