A ultrasonic welding method of joining dissimilar-material workpieces, such as sheet materials, and the joined components formed thereby. The method includes applying ultrasonic energy to a thermoplastic piece to fill a hole of a dissimilar piece to form a weld point that is made up with polymer from the thermoplastic piece. In general, the geometry of the thermoplastic piece is not altered during the process. The dissimilar piece generally has a higher melting temperate and can be metal, thermoset polymers, or other thermoplastic material. The welded pieces can be arranged in a lap, laminate, or double lap configuration. In some embodiments, the hole of the dissimilar sheet material includes undercut features that improve the mechanical interlock between the dissimilar pieces. In some embodiments, the weld point has a mushroom cap to improve mechanical interlock.

Composite structures and methods of forming composite structures are provided. The composite structures can include one or more composite structure components. Each composite structure component is formed from a composite panel that includes one or more sheets of material. The sheets of material include a thermoplastic material and a plurality of reinforcing fibers. A composite panel can be formed in three dimensions to form a composite structure component. Multiple composite structure components can be fused to one another to form a composite structure. In addition, each composite structure component and the composite structure formed therefrom can include an aperture. An interior volume can be formed between adjacent composite structure components. Methods for forming a composite structure can include a step of simultaneously molding and fusing composite structure components.

A method of joining includes disposing a second workpiece adjacent to a first workpiece. The method further includes identifying a determined hardness parameter of at least one of the first and second workpieces at a welding position. The determined hardness parameter is determined by at least one of estimation, calculation, and measurement. The method includes selecting a weld schedule based on the determined hardness parameter and welding the first and second workpieces together using the selected weld schedule. A welding horn includes a shank and a tip having an end face, the tip being disposed at an end of the shank and configured to contact a workpiece and to transmit energy to the workpiece. Knurls are disposed on the end face, each knurl having a distal end. A curved indenter extends from the end face beyond the distal ends of the knurls.

A method for joining together different components or different sections of a single component, wherein at least one of the components is a thermoplastic fiber composite component, by using a threaded fastener. Heat is used for softening the thermoplastic fiber composite component to be joined together with the threaded fastener. A joined-together fiber composite component of a vehicle, aircraft or spacecraft, can be obtained by the disclosed method.

Disclosed are thermoset/thermoplastic composites that include a thermoset component directly or indirectly bonded to a thermoplastic component via a crosslinked binding layer between the two. The crosslinked binding layer is bonded to the thermoplastic component via epoxy linkages and is either directly or indirectly bonded to the thermoset component via epoxy linkages. The composite can be a laminate and can provide a route for addition of a thermoplastic implant to a thermoset structure.

A method of joining workpieces includes the steps of bringing a first workpiece and a second workpiece together, induction heating a susceptor material, and pressing the workpieces together. Each workpiece may include a thermoplastic material, and the workpieces are brought together at a joint interface so that a protrusion of the first workpiece is aligned with a receptacle of the second workpiece. The susceptor material is in contact with the thermoplastic material of the first workpiece during heating such that the thermoplastic material of the first workpiece softens. The step of pressing is performed while the thermoplastic material of the first workpiece is softened, thereby reshaping the first workpiece where the susceptor material is in contact with the thermoplastic material of the first workpiece. The protrusion is deformed to form an interlock with the receptacle at the joint interface.

Laser transparent compositions that may be black in color. The laser transparent compositions may include a matrix material that includes a polypropylene, a dye system that includes one, and optionally two or more, polar organic compounds, a plurality of glass fibers, and a UV stabilizer. Methods of laser welding, which may include irradiating a laser absorbing composition that contacts a laser transparent composition at an interface.

A method of bonding a second object to a first object includes: providing the first object having a thermoplastic liquefiable material in a solid state; providing the second object having a surface portion that has a coupling structure with an undercut, so that the second object is capable of making a positive-fit connection with the first object; pressing the second object against the first object with a tool that is in physical contact with a coupling-in structure of the second object while mechanical vibrations are coupled into the tool; continuing to press and couple vibrations into the tool until a flow portion of the thermoplastic material of the first object is liquefied and flows into the coupling structures of the second object; and letting the thermoplastic material re-solidify to yield a positive-fit connection between the first and second objects by the re-solidified flow portion interpenetrating the coupling structures.

Methods of bonding a first object to a second object, including the steps of: providing the second object having a protrusion; providing the first object having a thermoplastic material; positioning the first object relative to the second object such that an assembly of the first and the second object is formed; applying a relative force between the second and first objects and applying mechanical vibration to the assembly of the first and the second object until at least a flow portion of the thermoplastic material becomes flowable and flows around the protrusion; and causing the thermoplastic material to re-solidify. The first object may be a connecting element including a feedthrough, wherein the second object has a corresponding opening. The protrusion may be deformed such that the protrusion has an undercut relative to an axis along which the first and second objects are pressed against each other.

A composite structure (1) for an aircraft, having at least one insert (2) for receiving attachment devices, each insert (2) includes a core (3) having a major dimension and containing at least one through-hole (4), and a composite strip arrangement formed by a first section (5) surrounding the core (3) and attached to said core (3) by an adhesive polymeric layer, and a second section (6) including at least one free end (6a). The first (5) and the second portion (6) of the composite strip arrangement are disposed over a first surface (1a) of the composite structure (1), such that the major dimension of the core (3) is positioned transversal to said first surface (1 a). The at least one insert (2) is co-cured with the composite structure (1).