A method and manufacturing unit for producing a rotor blade (5) of a wind turbine (1) from at least a first rotor blade element (11, 11, 12, 12) and a second rotor blade element (11, 11, 12, 12). The first rotor blade element (11, 11, 12, 12) and the second rotor blade element (11, 11, 12, 12) are positioned in the desired relative arrangement with respect to each other such that a joint gap (13) remains between the first rotor blade element (11, 11, 12, 12) and the second rotor blade element (11, 11, 12, 12). Adhesive is introduced into the joint gap (13) for joining the first rotor blade element (11, 11, 12, 12) and the second rotor blade element (11, 11, 12, 12).

A rotary wing aircraft that comprises a structural arrangement with at least one first fiber reinforced polymer component and at least one second fiber reinforced polymer component that are spaced apart from each other by an interspace and that are rigidly attached to an associated structural component, wherein the at least one first fiber reinforced polymer component and the at least one second fiber reinforced polymer component are at least partly interconnected by means of an electrically conductive connection, and wherein the electrically conductive connection comprises at least one sprayed layer of electrically conductive particles, the at least one sprayed layer of electrically conductive particles being provided in the interspace.

A method for connecting a surface-structured workpiece (SSW) and a plastic workpiece using a joining tool with a sonotrode. The method includes: positioning the SSW and the plastic workpiece on an anvil such that a structured contact surface section (SCSS) of the SSW faces a contact surface of the plastic workpiece; positioning the sonotrode in contact with an outer surface of the SSW that is opposite to the SCSS; and applying pressure to the sonotrode and/or the anvil perpendicular to the contact surface to hold the workpieces fixed between the anvil and the sonotrode and applying ultrasonic vibrations to the workpieces by the sonotrode for a predetermined period of time to induce softening of the plastic workpiece and penetrate pin-like elements of the SCSS into the plastic workpiece.

An adhesive (B) of solvent containing adhesive as a suspension of low viscosity is prepared by adding a solvent MIBK to a one-part epoxy adhesive of a dicyandiamide-curable type (A). Metal shaped articles (M1 to M5) as adherends are prepared each of which, through various surface treatment, has specific surface configuration of roughened face and/or ultrafine irregularities and the surface is entirely covered with a thin layer of ceramics such as a metal oxide or metal phosphate. The specified face of each metal shaped article (M1 to M5) is painted with the solvent containing adhesive (B). The faces painted with the adhesive of two metal shaped articles (M1 to M5) are caused to abut each other, the articles are heated to cure the one-epoxy adhesive to accomplish adhesion. With one of the adherends replaced by a CFRP shaped article (P2), a composite of a metal and CFRP can be formed.

A pi-shaped preform, an assembly including the same, and methods of making the same are disclosed herein. In some embodiments, a pi-shaped preform includes a base component, a pair of axially elongated legs coupled to the base component to define a channel between the axially elongated legs, and wherein the base component and the pair of axially elongated legs each comprises an oriented ply stack, wherein each ply in the oriented ply stack comprises aligned continuous fibers, and wherein at least one ply in the oriented ply stack comprises stitching fibers, wherein the stitching fibers hold together the aligned continuous fibers of the at least one ply.

A reinforcing device to provide an alternative improvement in the structural stability of laminated components includes a body structure having an abutment surface and at least one fastening area. The abutment surface extends along a first direction. In a cross-sectional direction, transverse to the first direction, the abutment surface includes a rounded contour section so abutment surface is configured to conform with a concave edge section of a laminated structural member. The at least one fastening area is provided at the body structure opposite to the abutment surface. The at least one fastening area is configured to secure the abutment surface against the concave edge section of the laminated structural member.

A method for applying adhesive to sides of a flange, such as in rotorcraft connection joints, includes attaching an intermediate member to an edge of a flange and flowing adhesive in gaps between sides of the flange and inner edges of a double lap joint element by inserting the flange with the intermediate member into the double lap joint element.

A method of reducing residual stress in a composite assembly may include assembling a first composite part to a second composite part to form a detail assembly. The first and second composite part may each have a flange and a web connected by a bend radius. The webs may be arranged back-to-back. The detail assembly may be cured on a compensated cure tool compensated for cure shrinkage spring-in predicted to occur in the first and second composite part. The method may include allowing the first and second composite part to spring in from cure shrinkage, and assembling the detail assembly to an uncured third composite. The method may also include co-bonding the detail assembly to the third composite part on an assembly cure tool to form a composite assembly having reduced cure shrinkage residual stress in the bend radii of the first and second composite part.

A thermoplastic composite structure is produced by extruding a bead of composite material to a desired cross sectional shape. An extruder extrudes the polymer bead containing reinforcing fibers, using a low compression first extruder stage where the polymer is mixed and de-gassed, and a high compression second stage where the polymer is consolidated and extruded. The cross sectional profile of the polymer bead may be altered using a variable extruder gate.

A thermoplastic composite structure is produced by extruding a bead of composite material to a desired cross sectional shape. An extruder extrudes the polymer bead containing reinforcing fibers, using a low compression first extruder stage where the polymer is mixed and de-gassed, and a high compression second stage where the polymer is consolidated and extruded. The cross sectional profile of the polymer bead may be altered using a variable extruder gate.