A method for joining two objects by anchoring an insert portion provided on one of the objects in an opening provided on the other one of the objects. The anchorage is achieved by liquefaction of a thermoplastic material and interpenetration of the liquefied material and a penetrable material, the two materials being arranged on opposite surfaces of the insert portion and the wall of the opening. Before such liquefaction and interpenetration, an interference fit is established in which such opposite surfaces are pressed against each other, and, for the anchoring, mechanical vibration energy and possibly a shearing force are applied, wherein the shearing force puts a shear stress on the interference fit.

To reduce the processing time in the case of repairing of excessively countersunk bolt openings or surface damage in fiber composite workpieces, it is proposed to countersink the corresponding surface spot to produce a contact surface and a depression for a fiber composite insert body. The fiber composite insert body is placed onto the contact surface and is fixed on the fiber composite workpiece in the depression. In the case of an excessively countersunk bolt opening, a new bolt opening is drilled into the fiber composite insert body, which new bolt opening is subsequently countersunk to the correct countersunk bore depth. In the case of the method, a three-legged application tool can be used which positions and orients the fiber composite insert body correctly and presses it onto the fiber composite workpiece during the curing of the adhesive.

A method for manufacturing a structural element of a wind turbine blade including forming of at least one injection hole in at least one laminate provided on a top side of a core material of a first portion and a second portion of the structural element and a bottom side of a core material of the first portion and the second portion, so that the at least one injection hole is fluidically connected to the cavity. Further, injecting adhesive through the injection hole into the cavity, curing the adhesive injected into the cavity and thereby forming a joint between an end of the core material of the first portion and an end of the core material of the second portion. Further, a method for manufacturing a wind turbine blade and the structural element, the wind turbine blade is also provided.

Polymeric based closed cell foams, such as shape memory polymer foams, contain bubbles. Making these bubbles continuous is called reticulation. Disclosed are embodiments of a device and method to controllably reticulate polymer-based closed cell foams by puncturing the membranes of these polymer-based closed cell foams.

A method for joining two objects by anchoring an insert portion provided on a first object in an opening provided on a second object. The anchorage is achieved by liquefaction of a thermoplastic material and interpenetration of the liquefied material and a penetrable material, the two materials being arranged on opposite surfaces of the insert portion and the wall of the opening. During the step of inserting the insert portion in the opening and/or during anchorage a clamping force is applied to opposing surfaces of the second object to prevent the second object from cracking or bulging.

High-frequency welding method for welding an accessory to a substrate by high-frequency welding machinery which includes a female mold, having a cavity formed by a profile having substantially the same shape and dimensions as the accessory, and a male mold, having a relief formed by a profile having substantially the same shape and dimensions as the accessory. The method includes: mounting the female mold on a movable upper plate of the machinery and the male mold on a fixed lower plate of the machinery, or vice versa, such that the profile of the cavity is aligned in a closure direction of the molds with the profile of the relief. The method further includes: positioning the accessory on the relief or in the cavity; positioning the substrate above the accessory; moving the upper plate towards the lower plate; supplying high-frequency welding energy to the upper plate and/or to the lower plate.

A method for joining two objects by anchoring an insert portion provided on one of the objects in an opening provided on the other one of the objects. The anchorage is achieved by liquefaction of a thermoplastic material and interpenetration of the liquefied material and a penetrable material, the two materials being arranged on opposite surfaces of the insert portion and the wall of the opening. Before such liquefaction and interpenetration, an interference fit is established in which such opposite surfaces are pressed against each other, and, for the anchoring, mechanical vibration energy and possibly a shearing force are applied, wherein the shearing force puts a shear stress on the interference fit.

A method for manufacturing a rivet connection of a fiber composite component. The method includes positioning a first component which contains a fiber composite material in an overlap joint with a second component, laser-drilling a shared through-hole at least through the fiber composite material of the first component, inserting a rivet into the through-hole and fixing the rivet to the first and to the second component.

A composite material with an insert-molded attachment steel is provided. The composite material includes a plurality of burring apertures, each of which has a flange in one direction on the attachment steel and is inserted between fibers. A resin is then introduced between the fibers in each burring aperture and external to the flange.

A joining method for joining a resin member and a metal member by heating is provided. Joining of the resin member and metal member is performed by heating a joining interface of the resin member and metal member to a temperature in a range of equal to or higher than a decomposition temperature of the resin member and lower than a temperature at which gas bubbles are generated in the resin member and by cooling a surface of the resin member on the opposite side from a joining surface thereof with the metal member to a temperature that is lower than the melting point of the resin member.