A method for welding at least two parts including a thermoplastic material and having respective surfaces to be welded, including: inserting an insert between the surfaces to be welded of the two parts; generating heat via the insert; wherein the insert moves in relation to the parts to be welded in a welding direction. Also, an installation adapted for implementation of this method.

A method for welding at least two parts including a thermoplastic material and having respective surfaces to be welded, including: inserting an insert between the surfaces to be welded of the two parts; generating heat via the insert; wherein the insert moves in relation to the parts to be welded in a welding direction. Also, an installation adapted for implementation of this method.

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.

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.

A composite rotatable assembly for an axial flow compressor comprises a spool having a plurality of blade assemblies arranged in stages on the spool and attached thereto by a wound band. Each blade assembly comprises a blade and a base, with the base having a forward tang extending axially forward of a leading edge of the blade and an aft tang extending axially aft of a trailing edge of the blade. The band is wound over at least a portion of the forward and aft tangs of the plurality of blade assemblies to hold the blade assemblies to the spool under centrifugal loading. An abradable layer may be added over the wound band.

A fastener comprising a polymer composition [composition (C)] comprising at least one polyaryletherketone polymer [(PAEK) polymer], and at least one nitride (NI) of an element having an electronegativity (ε) of from 1.3 to 2.5, as listed in <<Handbook of Chemistry and Physics>>, CRC Press, 64.sup.th edition, pages B-65 to B-158, based on the total weight of the composition (C).

Disclosed is a method of resistance welding between composite articles. A conductive element is provided between faying surfaces, having a plurality of lower resistivity electrode portions spaced apart along the length of the contact area between the composite articles. The electrode portions can be used to spot weld across the electrode portions, and along a longitudinal portion of the conductive element between the electrode portions by application of an electrical current. Also disclosed are apparatus for use in the resistance welding methods and composite articles and structures and elements incorporating the conductive element.

Disclosed is a method of resistance welding between composite articles. A conductive element is provided between faying surfaces, having a plurality of lower resistivity electrode portions spaced apart along the length of the contact area between the composite articles. The electrode portions can be used to spot weld across the electrode portions, and along a longitudinal portion of the conductive element between the electrode portions by application of an electrical current. Also disclosed are apparatus for use in the resistance welding methods and composite articles and structures and elements incorporating the conductive element.

A first member formed of a thermoplastic resin molding mixed with a fiber material and a second member formed of a molding containing at least a thermoplastic resin are welded by friction stir spot welding using a double-acting tool for friction stir spot welding. An overlapping part between the first member and the second member is formed, and the tool is disposed against the overlapping part while the pin and the shoulder are rotated about the rotation axis. The pin is plunged into the overlapping part, and friction stir is performed to cause extension fibers to remain around a plunging region of the pin while the shoulder is retracted to release an overflow material. The shoulder is brought closer to the overlapping part to wrap the extension fibers into the overflow material when the overflow material is backfilled while the pin is retracted from the overlapping part.

A first member formed of a thermoplastic resin molding mixed with a fiber material and a second member formed of a molding containing at least a thermoplastic resin are welded by friction stir spot welding using a double-acting tool for friction stir spot welding. An overlapping part between the first member and the second member is formed, and the tool is disposed against the overlapping part while the pin and the shoulder are rotated about the rotation axis. The pin is plunged into the overlapping part, and friction stir is performed to cause extension fibers to remain around a plunging region of the pin while the shoulder is retracted to release an overflow material. The shoulder is brought closer to the overlapping part to wrap the extension fibers into the overflow material when the overflow material is backfilled while the pin is retracted from the overlapping part.