Composite parts and processes for their manufacture

Abstract

The present invention relates to a composite part (1) comprising a hollow structure (3) and a foam component (5) inserted into the hollow structure (3), with a gap (15) formed between the hollow structure (3) and the foam component (5), wherein a tension-activated reinforcement structure (17) is connected to the foam component (5) and an end portion (19) of the tension-activated reinforcement structure (17) is connected to the hollow structure (3) such that the foam component (5) does not contact the hollow structure (3) and the gap (15) is formed between the hollow structure (3) and the foam component (5). The present invention further relates to a process for manufacturing a composite part.

Description

[Technical Field]

[0001] explanation The present invention relates to a composite part comprising a hollow structure and a foam part inserted into the hollow structure, forming a gap between the foam part and the hollow structure.

[0002] Foam parts inserted into hollow structures are used, for example, in the automotive industry as reinforcing inserts for mechanical reinforcement or as energy-absorbing inserts for absorbing energy in the event of a collision. Due to the construction of vehicle chassis, foam parts are usually inserted into the hollow structure before painting. For this reason, it is necessary to maintain a gap between the foam part and the hollow structure during the electrophoretic painting process. To achieve sufficient corrosion stability, all metal surfaces are coated with a corrosion inhibitor. To apply the corrosion inhibitor to all surfaces, the vehicle chassis is treated by electrophoretic painting. During electrophoretic painting, the vehicle chassis is immersed in a chemical bath containing a coating solution containing the corrosion inhibitor.

[0003] During immersion of the vehicle chassis in the chemical bath, the coating liquid reaches all free surfaces and the anticorrosion deposits on these free surfaces, and also flows into the gaps between the hollow structure and the foamed part, so that the coating liquid can also be applied to the surfaces of the hollow structure adjacent to the foamed part.

[0004] To provide the gap, currently, spacer points are formed on the outer surface of the foam part, for example in the form of spherical domes to minimize the contact area between the foam part and the hollow structure. Alternatively, the gap is provided by using adhesive pads that define the gap and hold the foam part at a desired distance relative to the surface of the hollow structure.

[0005] In addition to inserting foam parts into hollow structures, it is also known, for example from EP 2 383 170, to use insert parts made of a material with high tensile strength that can be inserted into hollow or U-profiles and have their ends connected to them to reinforce hollow or U-profiles. To achieve the reinforcing properties, a distance must be established between the insert part and the hollow or U-profile. This distance is achieved by spacing elements on one side of the profile and on the other side of the insert part.

[0006] It was an object of the present invention to provide a composite part comprising a hollow structure and a foam part, which allows for a simple fixation of the foam part with a continuous gap between the foam part and the hollow structure, and further improves the performance of the composite part, in particular with regard to energy absorption. A further object was to provide a process for manufacturing such a composite part.

[0007] This object is achieved by a composite part comprising a hollow structure and a foam part inserted into the hollow structure, with a gap formed between the hollow structure and the foam part, wherein a tension-active reinforcement structure is connected to the foam part and an end portion of the tension-active reinforcement structure is connected to the hollow structure such that the foam part does not contact the hollow structure and a gap is formed between the hollow structure and the foam part.

[0008] Surprisingly, the use of a tension active reinforcement structure can further enhance the energy absorption properties of the composite part, especially when no spacing elements are provided on one side of the hollow structure and on the other side of the tension active reinforcement structure. Furthermore, by connecting the end portions of the tension active reinforcement structure to the hollow structure, the fixation of the foam part within the hollow structure can be simplified.

[0009] It is part of the present invention that more than one tension active reinforcement structure can be used to better accommodate different mechanical loads.

[0010] The hollow structure may be a closed hollow structure, such as a tube or a closed channel, or an open hollow structure, such as a U-profile. If the hollow structure is a closed hollow structure, it may have any cross-sectional geometric shape, such as a circle, a triangle, a rectangle, or any other polygon. In addition to these channel-like geometries, the cross-sectional geometric shape of a closed channel may also include a recess or have an irregular cross-sectional area. If the hollow structure is an open hollow structure, it may also have any cross-sectional shape other than a U-shape, such as a V-shape, a W-shape, or a shape with a recess. Furthermore, regardless of whether the hollow structure is an open hollow structure or a closed hollow structure, the cross-sectional shape may vary along the hollow structure.

[0011] The hollow structure may be made from any suitable material, for example a metal or an optionally reinforced polymer. Preferably, the hollow structure is made from a metal, in particular steel or aluminum.

[0012] The foam part is preferably made from a polymer foam, however, besides polymer foam, any other foam material, for example, metal foam or glass foam, may also be used to manufacture the foam part.

[0013] Suitable polymers for producing foam parts can be, for example, polyurethanes or polyamides. Preferably, the polymer foam is a polyamide foam, such as a polyamide foam based on polyamide 6, polyamide 6 / 6.36, polyamide 12, polyamide 610, polyamide 6 / 66, polyamide 6.12, or a copolyamide.

[0014] Preferably, the polyamide is a polyamide, such as those described in WO 2020 / 016102, or a copolyamide, such as those described in WO 2021 / 052881.

[0015] Thus, polyamides may be used, for example, (i) 15 to 84 wt. % of at least one lactam; (ii) 16 to 85% by weight of a monomer mixture containing: (ii1) At least one C 32 -C 40 Dimer acid and (ii2) at least one C4-C 12 Diamine and The monomer mixture contains 45 to 55 mol % of component (ii1) and 55 to 45 wt % of component (ii2) based on the total amount of the monomer mixture, and the sum of component (i) and component (ii) is 100 wt %.

[0016] When the polyamide is a copolyamide, the polyamide may be, for example, (A) 5 to 75 weight percent of at least one copolyamide prepared by polymerization of: (A1) 15 to 84 wt. % of at least one lactam; (A2) 16 to 85% by weight of a monomer mixture containing the following: (M1) At least one C 32 -C 40 Dimer acid and (M2) At least one C4-C 12 Diamine (The total of components A1 and A2 is 100% by weight) and (B) 25 to 95% by weight of at least one polyamide different from the copolyamide (A) It may be a polymer mixture consisting of

[0017] Polyamide (B) is polycaprolactam (PA6), polybutylene adipamide (PA4.6), polyhexamethylene adipamide (PA6.6), polyhexamethylene sebacamide (PA6.10), polyhexamethylene dodecane amide (PA6.12), poly-11-aminoundecanamide (PA11), polylaurolactam (PA12), poly-m-xylylene adipamide (PAMXD 6), polypentamethylene sebacamide (PA510), 6T / Z (Z = lactam), 6T / 6I / XY, 6T / XT (X = linear or branched C4-C 18 diamine), XT (X=C4-C 18 diamine), PA PACM 12 (PACM = p-diaminodicyclohexylmethane), PA MACM 12 (MACM = 3,3-dimethyl-p-diaminodicyclohexylmethane), PA MPMD 6 (MPMD = 2-methylpentamethylenediamine), PA MPMD T, PA MPMD 12, polyhexamethylene isophthalamide (PA 6I), polyhexamethylene isophthalamide-co-hexamethylene terephthalamide (PA 6I / 6T), PA 6-3-T (a mixture of terephthalic acid polyamide and 2,2,4- and 2,4,4-trimethylhexamethylenediamine), polybutylene sebacamide (PA 4.10), polydecamethylene sebacamide (PA 10.10), polypentamethylene adipamide (PA 5.6), PA 6 / 66 and PA 66 / 6, PA 6Y (Y=C4-C 18 diacids), and their transamination products.

[0018] The use of polyamide foam has the advantage that such foam parts made from polyamide foam are temperature stable, especially with regard to the temperatures that occur during the coating process.

[0019] The polymer of the polymer foam may contain additives such as reinforcing additives, dyes, plasticizers, stabilizers, e.g., UV stabilizers and / or flame retardants, to set the properties of the polymer foam. When the polymer for the polymer foam contains reinforcing additives, these may be, for example, short fibers or powder additives such as talcum. When short fibers are used, the fibers may be, for example, carbon fibers, glass fibers, aramid fibers, or mineral fibers.

[0020] The foamed part may be made from open-cell or closed-cell foam. Additionally, the foamed secondary component may also be made from a combination of open-cell and closed-cell foam, including open and closed cells. The foam from which the foamed part is made may be particle foam or open-cell foam, with particle foam being preferred.

[0021] The foam part can have any cross-sectional shape that allows it to be inserted into the hollow structure and form a gap between the inner wall of the hollow structure and the surface of the foam part. The foam part can have a cross-sectional shape that corresponds to the cross-sectional shape of the hollow structure, but is slightly smaller. These corresponding shapes allow for a regular gap between the hollow structure and the molded part. However, depending on the desired properties of the composite part, the foam part can also have a cross-sectional shape that differs from the cross-sectional shape of the hollow structure, for example, by providing recesses or protrusions in the foam part at locations where there are no recesses or protrusions in the hollow structure.

[0022] The tension-active reinforcing structure used in the composite part is preferably made of a material that can reinforce the composite part when a bending load acts on the composite part. Suitable materials are, for example, metals that allow elastic deformation or act like springs. Suitable materials for the tension-active reinforcing structure are, for example, continuous fiber-reinforced polymers, or preferably, metals. Suitable metals for the tension-active reinforcing structure can be, for example, steel or aluminum. The material of the tension-active reinforcing structure is preferably made of the same material as the hollow structure to facilitate mechanical connection (e.g., welding) between the two materials.

[0023] The tension-active reinforcement structure can have any suitable shape. Preferably, the tension-active reinforcement structure is a beam, strip, or rod. Therefore, the shape of the tension-active reinforcement structure is such that at least two end portions of the tension-active reinforcement structure protrude from the foam component.

[0024] In the composite part, the foam part is connected to the tensile-active reinforcing structure. To connect them, the tensile-active reinforcing structure is preferably integrated into the foam part, so that the foam part at least partially surrounds the tensile-active reinforcing structure. Alternatively, it is possible for the tensile-active reinforcing structure to be connected to one surface of the foam part, so that in the composite part, one surface of the tensile-active reinforcing structure faces the inner surface of the hollow structure. However, preferably, the foam part surrounds the tensile-active reinforcing structure so that only the end portions of the tensile-active reinforcing structure protrude from the foam part.

[0025] The protruding end portion can be connected to the hollow structure and is shaped in such a way that after connecting the end portion to the hollow structure, a gap is formed between the foam part and the hollow structure, the gap preferably surrounding the entire foam part so that there is no contact between the foam part and the hollow structure. To this end, the end portion can be, for example, S-shaped, U-shaped, or can include a portion directed toward the inner surface of the hollow structure and a second portion subsequent to the portion directed toward the inner surface of the hollow structure, the second portion being aligned parallel to the surface of the hollow structure to allow connection of the second portion to the hollow structure.

[0026] Any connection method known to those skilled in the art can be used to connect the end portions of the tension-active reinforcement structure to the hollow structure. Suitable connection methods include, for example, screwing, riveting, gluing, welding, soldering, or a combination thereof. In particular, when the tension-active reinforcement structure and the hollow structure are made of metal, particularly steel or aluminum, the end portions of the tension-active reinforcement structure are welded or soldered to the hollow structure. Welding, soldering, or gluing the end portions of the tension-active reinforcement structure to the hollow structure has the added advantage that the connection is a material bond. Therefore, when the composite part is subjected to electrophoretic coating to apply a corrosion inhibitor, it is not necessary to apply the corrosion inhibitor to the portion of the hollow structure to which the end portions are connected and to the portion of the end portion of the tension-active reinforcement structure attached to the hollow structure.

[0027] The use of a reinforcing structure improves the anti-corrosion coating process of hollow structures, as it allows corrosion inhibitors and other liquids to flow cleanly through the gaps, thus improving the corrosion protection effect.

[0028] A process for manufacturing such a composite part comprising a hollow structure and a foam part inserted into the hollow structure, with a gap formed between the hollow structure and the foam part, comprises: (a) forming a hollow structure; (b) forming a foam component having a tension-activated reinforcement structure inserted therein, wherein an end portion of the tension-activated reinforcement structure protrudes from the foam component; (c) attaching an end portion of the tension activated stiffening structure to the hollow structure; Includes.

[0029] The hollow structure may be formed by any process for forming hollow structures known to those skilled in the art. If the hollow structure is an open hollow structure, it may be formed, for example, by bending a flat sheet into the desired shape.

[0030] If the hollow structure is a closed hollow structure, it can be formed by any process for forming a profile known to those skilled in the art, for example, by manufacturing at least two profile sections and connecting the profile sections by roll forming or extrusion. Other techniques for forming hollow structures are pultrusion or extrusion to form a closed profile that is not welded.

[0031] When a hollow structure is formed by manufacturing at least two profile sections and connecting them, the connection can be realized by any connection method known to those skilled in the art. The profile sections can be connected, for example, by welding, gluing, soldering, screwing, or riveting. In particular, when the profile sections are connected by screwing or riveting, the profile sections can be arranged so that parts of the walls of the profile sections overlap and the rivets or screws are guided through the overlapping walls. Alternatively, each profile section can be provided with a flange, which can be connected to form the hollow structure.

[0032] When closed hollow structures are formed by roll forming, a profile is first formed from a coil. To form the profile, the edges of the sheet from the coil are bent so that they meet. After forming the profile, the abutting edges are welded, thus producing a closed hollow structure.

[0033] The extrusion process for producing hollow structures can also be used to produce open or closed hollow structures. Forming hollow structures by extrusion has the advantage that, due to the pressing of metal through a die, any shape of profile can be produced, including shapes that cannot be produced by roll forming or bending.

[0034] In a second step, which can be performed independently of the formation of the hollow structure, a foam part with an inserted tension-active reinforcement structure is formed. The hollow structure and the foam part with an inserted tension-active reinforcement structure can be produced simultaneously or in stages. If the components are produced sequentially, the hollow structure can be produced first, followed by the foam part with the inserted tension-active reinforcement structure, or the foam part with the inserted tension-active reinforcement structure can be produced first, followed by the formation of the hollow structure. Furthermore, particularly when multiple composite components are to be produced, all necessary hollow structures and all necessary foam parts with inserted tension-active reinforcement structures can be formed separately, and after the separate components are produced, all foam parts with inserted tension-active reinforcement structures can be connected to the hollow structure.

[0035] To manufacture a foamed part with an inserted tension-active reinforcing structure, the tension-active reinforcing structure is generally first formed. The tension-active reinforcing structure can be formed, for example, by casting, or preferably by a pressing or deep-drawing process.

[0036] When the foam part is made from an open-cell foam, it is preferable to place a tension-activated reinforcing structure in a mold, and then inject a polymer melt containing a blowing agent or a polymer-producing reactant and a blowing agent into the mold to form the foam part in the mold. In the mold, the blowing agent expands to form a polymer foam. When a polymer-producing reactant is injected into the mold, the reactant reacts during expansion to form a polymer. Injecting the reactant into the mold is particularly preferable when the polymer is thermosetting. Injecting a polymer-containing blowing agent into the mold is preferable for thermoplastic polymers. In this case, a polymer melt is injected into the mold, and the foam part is produced by an injection molding process.

[0037] When a foam part is made from particle foam, the foam part with the inserted tension-activated reinforcing structure can be formed, for example, by placing the tension-activated reinforcing structure in a mold, injecting expanded polymer beads into the mold, and connecting the expanded polymer beads to form the foam part. The particle foam is preferably made from a thermoplastic polymer. To connect the expanded polymer beads, superheated steam is typically injected into the mold under pressure. The superheated steam begins to melt the surfaces of the expanded polymer beads, thus welding the expanded polymer beads together to form the particle foam.

[0038] After the hollow structure and the foam part with the inserted tensile active reinforcement structure are manufactured, the hollow structure and the foam part with the inserted tensile active reinforcement structure are connected.

[0039] To connect the foam part with the inserted tension-active reinforcement structure to the hollow structure, the end portion of the tension-active reinforcement structure protruding from the foam part is attached to the hollow structure. The end portion of the tension-active reinforcement structure can be attached to the hollow structure by welding, gluing, screwing, riveting, soldering, or a combination thereof. Preferably, the end portion of the tension-active reinforcement structure is attached to the hollow structure by welding, gluing, or soldering, particularly by welding.

[0040] The composite part thus produced may be further finished, for example by coating.

[0041] Typically, the composite part is part of a larger structure, such as a vehicle chassis. In this case, the composite part and additional parts are connected to form the larger structure, and the larger structure may then be subjected to a coating process. If the larger structure is a vehicle chassis, the vehicle chassis is typically electrophoretically painted to apply a corrosion inhibitor to the chassis before spraying a color coating onto the vehicle. After each coating step, the chassis is passed through a drying oven to dry and cure the coating layer. Due to the temperatures in the drying oven and the electrophoretic painting bath, the foam part needs to be made from a temperature-stable material. Therefore, it is preferable to use a temperature-stable polyamide to form the composite part.

[0042] Embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description. [Brief explanation of the drawings]

[0043] [Figure 1] FIG. 2 is a three-dimensional schematic view of a hollow structure and a foam part inserted into the hollow structure. [Figure 2] 1A and 1B are schematic diagrams of hollow structures with embedded composite parts made from foam parts with inserted tension active reinforcement structures. [Figure 3] FIG. 10 shows a foam part with embedded tension active reinforcement structures under bending load. [Figure 4a] 1A-1C illustrate different possible cross-sectional shapes of foam parts. [Figure 4b] 1A-1C illustrate different possible cross-sectional shapes of foam parts. [Figure 4c] 1A-1C illustrate different possible cross-sectional shapes of foam parts. [Figure 4d]1A-1C illustrate different possible cross-sectional shapes of foam parts. [Figure 5] FIG. 10 shows simulated force-displacement curves for a hollow structure, a hollow structure with a foam component, a hollow structure with a tension-active reinforcement structure, and a hollow structure with a foam component and a tension-active reinforcement structure.

[0044] FIG. 1 shows a schematic representation of a hollow structure and a foam part to be inserted into the hollow structure.

[0045] The composite part 1 comprises a hollow structure 3 and a foam part 5. In the embodiment shown herein, the hollow structure 3 comprises a first profile section 7 and a second profile section 9 connected to form a closed hollow profile 3. To connect the first and second profile sections 7 and 9, the first and second profile sections 7 and 9 each comprise a flange 11, which is placed one above the other and connected. To connect the flanges 11, for example, screws or rivets can be used. Furthermore, it is also possible to connect the flanges by welding, soldering, or gluing.

[0046] In addition to using flanges as shown in Figure 1, the first and second profile sections 7 and 9 can also be connected by sliding one of the profile sections over the other so that parts of the walls of the first and second profile sections are in contact, and the first and second profile sections can be connected by screwing, riveting, gluing, soldering or welding. If the first and second profile sections are connected by welding or soldering, it is also possible to position the edges of the profile sections and connect the edges.

[0047] After forming the hollow structure 3 , the foam piece 5 is inserted into the hollow structure 3 , as indicated here by the arrow 13 .

[0048] A schematic cross-sectional view of the composite part 1 is shown in FIG.

[0049] In the composite part, the foam part 5 is located within the hollow structure 3 such that a gap 15 is formed between the foam part 5 and the hollow structure 3. The gap 15 is thereby formed such that the entire surface of the foam part 5 does not contact the hollow structure 3.

[0050] To position the foam part 5 within the hollow structure 3, a tension-activated reinforcing structure 17 is used. The tension-activated reinforcing structure 17 is embedded within the foam part 5, with only an end portion 19 protruding from the foam part 5. The end portion 19 comprises a portion 21 oriented toward the inner surface 23 of the hollow structure 5 and a second portion 25 aligned parallel to the inner surface 23 of the hollow structure 3.

[0051] To secure the foam part 5 within the hollow structure 3, the second portion 25 of the end piece 19 is secured to the inner surface 23 of the hollow structure 3. The securing of the second portion 25 of the end piece 19 can be achieved by any securing method known to those skilled in the art, such as screwing, riveting, welding, soldering or gluing, with welding, soldering or gluing being preferred.

[0052] The tension active reinforcing structure 17 and foam component 5 support the hollow structure 5 in absorbing energy when an impact acts on the composite component. The tension active reinforcing structure 17 is preferably positioned within the hollow structure 5 such that the tension active reinforcing structure 17 bends toward the side of the hollow structure 5 on which the second portion 25 is mounted. Such a variation of the foam component 5 with an embedded tension active reinforcing structure 17 is exemplarily shown in FIG. 3 .

[0053] During impact 27, the composite part 1, including the foam part 5 and the tension-active reinforcement structure 17, deforms, and this deformation absorbs the energy of the impact. The tension-active reinforcement structure 17 and the foam part 5 support the energy absorption properties of the composite part, and in particular increase the load that can be absorbed by the composite part before it ultimately fails. On this side, as the impact acts on it, the foam part is compressed and compressive stresses act on the foam part and the tension-active reinforcement structure, while on the other side, tensile stresses act on the foam part and the tension-active reinforcement structure.

[0054] Furthermore, as shown in Figure 3, the tension active reinforcing structure 17 is positioned within the foam part 5 in an area of ​​positive stress under bending. This allows the tension active reinforcing structure 17 to absorb high tension forces despite being bent because the compressive strength of the foam part 5 allows the tension active reinforcing structure 17 to stay in place and contribute to bending stiffness.

[0055] If there are multiple loading directions that differ depending on the location of the tension and compression distribution, it is preferable to use two or more reinforcing structures to ensure that in the case of mechanical loading, at least one of them is under tension.

[0056] Different shapes of foam parts that can be inserted into the rectangular hollow structure 3 are shown in Figures 4a-4d.

[0057] 4a and 4b, the foam part 5 has a rectangular cross-sectional shape with rounded edges. By using a foam part 5 with such a shape, it is possible to achieve a gap between the foam part 5 and the hollow structure 3 with a substantially uniform width.

[0058] In addition to the tension-active reinforcing structure 17 for providing a gap between the foam part 5 and the hollow structure 3, additional spacers 29 can be arranged between the hollow structure 3 and the foam part 5 to adjust the gap 15.

[0059] In particular, to reduce the mass of the composite part, it may be advantageous to form recesses 31 in the surface of the foam part 5, as shown in Figures 4c and 4d, for example, which maintain the energy absorption properties, and in particular the support function, of the foam part 5 despite the reduced mass of the foam part 5.

[0060] In FIG. 5, force-displacement curves for hollow structure 3, hollow structure 3 with foam part 5, hollow structure 3 with tension-active reinforcing structure 17, and hollow structure 3 with foam part 5 and tension-active reinforcing structure 17 are shown to highlight the mechanical improvements possible with the described invention.

[0061] In the diagram of FIG. 5, the abscissa 33 indicates the magnitude of the displacement in mm and the ordinate 35 indicates the magnitude of the force in N.

[0062] The force-displacement curve of hollow structure 3 without foam component 5 and without tension-active reinforcement structure 7 is shown by solid line 37, the force-displacement curve of hollow structure 3 with tension-active reinforcement structure 7 but without foam component 5 is shown by dashed line 39, the force-displacement curve of hollow structure 3 with foam component 5 but without tension-active reinforcement structure 17 is shown by dash-dot line 41, and the force-displacement curve of composite component 1 of the present invention with hollow structure 3, foam component 5, and tension-active reinforcement structure 17 is shown by dotted line 43.

[0063] As can be seen, the force that can be absorbed by the structure first increases, exceeds a maximum value, and then decreases again for hollow structure 3 without foam parts and tension-active reinforcement structure, and hollow structure 3 with only tension-active reinforcement structure 17, with hollow structure 3 with tension-active reinforcement structure 17 being able to absorb more force than hollow structure 3 without any reinforcement components.

[0064] When the hollow structure 3 comprises a foam element 5, the force that can be sustained reaches a maximum value, after which it decreases only slightly.

[0065] A composite part comprising a foam component 5 and a tension-active reinforcement structure 17 can sustainably support much greater forces than other structures, the maximum of which is higher than would be expected by applying additional forces that can be absorbed by the foam component 5 alone or by the tension-active reinforcement structure 17 alone.

[0066] Since the induced energy is directly proportional to the integral of the force-displacement curve, the energy absorbed by a component is proportional to the force applied. Therefore, all previous conclusions apply to both force and absorbed energy.

Claims

1. A composite component (1) comprising a hollow structure (3) and a foam component (5) inserted into the hollow structure (3), with a gap (15) formed between the hollow structure (3) and the foam component (5), wherein a tension-active reinforcement structure (17) is connected to the foam component (5) and an end portion (19) of the tension-active reinforcement structure (17) is connected to the hollow structure (3) such that the foam component (5) does not contact the hollow structure (3) and the gap (15) is formed between the hollow structure (3) and the foam component (5).

2. 2. A composite part according to claim 1, wherein the hollow structure (3) is made of metal.

3. The composite part of claim 2 , wherein the metal is steel or aluminum.

4. A composite part according to any one of claims 1 to 3, wherein the foam part (5) is made from polymer foam.

5. The composite part of claim 4 , wherein the polymer foam is one of a polyurethane foam or a polyamide foam.

6. 6. A composite part according to claim 4 or 5, wherein the polymer foam is a particle foam.

7. 7. A composite part according to any one of claims 1 to 6, wherein the tension active reinforcement structure (17) is a beam, strip or rod.

8. The composite part according to any one of claims 1 to 7, wherein the tension active reinforcement structure (17) is made from metal.

9. A method for manufacturing a composite part according to any one of claims 1 to 8, comprising the steps of: (a) forming a hollow structure (3); (b) forming a foam component (5) with a tension-activated reinforcement structure (17) inserted therein, the end portions (19) of the tension-activated reinforcement structure (17) protruding from the foam component (5); (c) attaching the end portion (19) of the tension active reinforcement structure (17) to the hollow structure (3).

10. 10. The method of claim 9, wherein the end portion (19) of the tension active reinforcement structure (17) is attached to the hollow structure (3) by welding, gluing, screwing, riveting, soldering, or a combination thereof.

11. 10. The method according to claim 9, wherein the hollow structure (3) is formed by manufacturing at least two profile sections (7, 9) and connecting the profile sections (7, 9) by roll forming or extrusion.

12. 12. The method according to any one of claims 9 to 11, wherein the foam part (5) with the tension-activated reinforcement structure (17) inserted therein is formed by placing the tension-activated reinforcement structure (17) in a mold, injecting a foaming agent containing a polymer melt or a reactant for producing a polymer and a foaming agent into the mold, and forming the foam part (5) in the mold.

13. 12. The method of any one of claims 9 to 11, wherein the foam part (5) with the inserted tension-active reinforcement structure (17) is formed by placing the tension-active reinforcement structure (17) in a mold, injecting expanded polymer beads into the mold, and connecting the expanded polymer beads to form the foam part (5).

Images