Method for producing structural component and structural component
By alternately applying material layers on both sides of the central workpiece of the motor vehicle structural member, combined with the wire-based surfacing additive manufacturing method, the existing structural members are solved, and the manufacturing of lightweight, low-cost and high-flexible structural members is realized.
Patent Information
- Application Number
- CN202380073232.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-02-01
- Filing Date
- 2023-11-28
- Publication Date
- 2025-05-30
AI Technical Summary
The existing motor vehicle structural components are heavy and have high manufacturing costs, making it difficult to achieve weight reduction and low-cost manufacturing.
Using wire-based surfacing additive manufacturing method, combined with prefabricated central workpieces, the geometric structure is expanded by alternately applying material layers on both sides of the central workpiece to form a lightweight and low-cost structural member.
Weight reduction of structural components and manufacturing cost reduction are achieved, while improving the flexibility and rapid feasibility of components.
Smart Images
Figure CN120076898A_ABST
Abstract
Description
Field of the Invention
[0001] The present invention relates to a method for manufacturing a structural member and a structural member. Background Art
[0002] In a motor vehicle, structural members perform a supporting task and define the stability and crash safety of the vehicle. Usually, structural members are manufactured as steel welded structures from sheet materials and formed parts. Such structural members are often too heavy. In addition, there are known structural members which are manufactured as composite members, for example, in the case of using fiber composite plastics. Such structural members are expensive to manufacture. Summary of the Invention
[0003] In this context, the object of the present invention is to provide an improved feasibility for manufacturing structural members for motor vehicles. In particular, it is now possible to achieve weight reduction and low-cost manufacturing.
[0004] The object is solved by the method for manufacturing a structural member according to claim 1 and the structural member according to claim 9. Other advantageous designs result from the dependent claims and the following description.
[0005] The present invention provides a method for manufacturing a structural member, the method having the following steps:
[0006] - Providing a central workpiece including at least one finished area,
[0007] - Positioning the central workpiece in a predetermined position in a manufacturing apparatus for wire-based surfacing using the finished area,
[0008] - Geometrically expanding the central workpiece on a first side of the central workpiece with a first member section, and
[0009] - Geometrically expanding the central workpiece on a second side of the central workpiece with a second member section, the second side being opposite to the first side,
[0010] wherein the geometric expansion of the central workpiece is performed by layerwise applying material by means of wire-based surfacing.
[0011] The central workpiece is formed, for example, from a sheet, (extruded) shaped part or casting. The sheet can be preformed, for example chamfered, deep-drawn, etc. The central workpiece has at least one finished machined area. The finished machined area is in the state required in a finished structural member. For example, the finished machined area can be a abutment surface that has been finally surface machined. The central workpiece can, for example, be a semi-finished product, so that individual areas have not yet been machined, or the central workpiece can be provided as a completely finished machined component. Preferably, the central workpiece is composed of metal or a metal alloy.
[0012] The at least one finished machined area of the central workpiece is used to position the central workpiece in a manufacturing device for wire-based surfacing. For example, a handling device, such as an industrial robot, can grip and clamp the central workpiece at the finished machined area.
[0013] The manufacturing device for wire-based surfacing is set up to convert a linear material into a molten state and to apply the material to the central workpiece in layers. Here, the molten material is materially bonded to the central workpiece onto which it is applied or to the material. In a particularly preferred design, the first and second component sections are produced by means of WAAM or laser DED. In Wire Arc Additive Manufacturing (WAAM), a metal wire is melted using an electric arc and applied to the component in layers in a desired shape, for example with the aid of a multi-axis manipulator. The Laser Direct Energy Deposition method (Laser DED) proceeds similarly, but the wire is melted with the aid of laser radiation. The two methods are characterized by a very high application rate and a high degree of flexibility in terms of the applicable geometries. This enables weight reduction based on the increased degrees of freedom in the manufacturing method. In addition, components with a very high ductility can be constructed using this method when using the corresponding wire.
[0014] By using a central workpiece, the share of structural components produced by additive manufacturing is reduced. Thereby, the manufacturing time is reduced and the manufacturing costs can be lowered. It has been recognized within the scope of the present invention that by combining a wire-based additive manufacturing method with a prefabricated central workpiece, the advantages of both methods can be combined in an optimized manner. This specifically means that the cost advantages of conventional manufacturing methods (such as casting methods or sheet metal forming methods) and the advantages of additive manufacturing are combined with respect to high flexibility in component design and the resulting weight reduction, low costs, and rapid feasibility of component changes. With the hybrid construction of the structural component according to the invention, the present invention departs from the hitherto common assumption that a structural component should be constructed integrally, at least when the material type should be the same.
[0015] In one preferred design, the central workpiece has its final geometric theoretical shape at the start of the method. The final geometric theoretical shape corresponds to the desired shape in the finished structural component. In particular, the geometric theoretical shape can predetermine the surface orientation (such as the flatness of the surface or the desired curvature).
[0016] Alternatively, in one design it is provided that the central workpiece has an initial shape deviating from the final geometric theoretical shape at the start of the method, the initial shape being determined such that the central workpiece is transformed into the final geometric theoretical shape by thermal deformation occurring during the method. For example, the component deformation occurring during the method can be simulated in a preparation phase or determined experimentally. The component deformation then acts, for example, in the negative direction on the final geometric theoretical shape, thereby obtaining the initial shape of the central workpiece. The thermal deformation during the method then ensures that the central workpiece is transformed back into the final geometric theoretical shape.
[0017] The component section and the second component section are manufactured by layerwise material application to a central workpiece. The first and second component sections preferably assume structural tasks in the structural component and can, for example, represent parts of the load path. It can be provided that the first component section is completed first and then the second component section is produced. The manufacturing equipment for wire-based welding can be designed to position the central workpiece in such a way that the material application can be carried out optimally. For example, the operating device can be designed to rotate the central workpiece, whereby, for example, the material application can be carried out in the direction of gravity. Particularly advantageous for minimizing component deformation is to alternately produce the cladding of the first component section and the cladding of the second component section. For example, the central workpiece can be oriented such that the first layer of material is applied on one side. Subsequently, the central workpiece is rotated, for example, by 180 degrees so that the second side is on top and the first layer of material is applied there. These steps are repeated, whereby the first and second component sections grow evenly into space. If the first or second component section is completed, the method is continued only on the side of the other component section in order to also complete that component section. By alternately applying material layers on opposite sides of the central workpiece, the heat input is improved and a (nearly) deformation-free construction of the central component can be achieved. This method is particularly advantageous to apply especially in cases where the central workpiece already has the final theoretical geometric shape at the start of the method.
[0018] In order to provide the feasibility for fastening to a vehicle in a simple manner, the central workpiece can, in one design, have fastening points at the start of the method that are required on the completed structural component. These fastening points can be, for example, threads, receiving holes, connection surfaces for welding, etc. That is, the fastening points can already be manufactured on the central workpiece. Since the central workpiece can be significantly smaller than the completed structural component, the handling is simpler and smaller equipment can be used. Correspondingly, the manufacture of the fastening points is simplified.
[0019] Particularly advantageous for the low-cost manufacture of the structural component is to use fastening points for positioning the central workpiece at the start of the method, which are constructed in the finished machining area and are required on the completed structural component. For example, these fastening points or also multiple fastening points, such as openings, threads or through-holes required on the completed structural component, can be used to fix the operating equipment thereon. Thus, not only is the precise positioning on the operating equipment ensured, but two functions are combined in one feature.
[0020] In one design, the central workpiece consists of a sheet metal. The sheet metal can, for example, be bent, cut, drilled or otherwise processed. Using sheet metal as the central workpiece enables a particularly low-cost manufacture.
[0021] Preferably, the central workpiece is a plate-shaped body. The plate-shaped body preferably has a thickness that is much smaller than the remaining dimensions of the plate-shaped body. For example, the thickness can be in the range of a few millimeters, such as less than 5 mm. The plate-shaped body can in particular be used as a base plate for the construction on both sides of the first and second component sections. The susceptibility of the plate-shaped body to thermal deformation can be compensated for according to the invention in such a way that the construction of the first and second component sections is preferably carried out alternately. For this purpose, it can also be advantageous to already take into account the component deformations occurring during the manufacture of the plate-shaped body and to provide the plate-shaped body with an initial shape that deviates from the final geometric theoretical shape.
[0022] In one design, the first and / or second component section has a hollow body. Thereby, a particularly light construction of the structural member can be achieved. By constructing the first and second component sections from the central workpiece in two opposite directions, a degree of freedom of the geometric structure can be achieved, which degree of freedom could otherwise only be constructed with a costly and time-consuming support structure in a generative manufacturing method. For example, the first and second component sections can have a hollow body structure that tapers towards the free ends from the central workpiece.
[0023] Furthermore, a structural member is provided, which structural member comprises: a central workpiece having at least one exposed area; a first component section manufactured by wire-based surfacing, which first component section is attached to the central workpiece on a first side of the central workpiece; and a second component section manufactured by wire-based surfacing, which second component section is attached to the central workpiece on a second side of the central workpiece opposite the first side. The exposed area is used during the manufacture of the additively manufactured component section for receiving and positioning the central workpiece in a manufacturing device and accordingly remains free of an additively manufactured additional structure. Preferably, the structural member is constructed using the above method and achieves the same technical effects and advantages as described for the method.
[0024] The structural member is preferably a structural member for a motor vehicle and is, for example, a body member, such as a tunnel reinforcement for a vehicle body.
[0025] Other advantages, features, and details of the invention result from the following description, in which embodiments of the invention are described in detail with reference to the drawings. Here, the features mentioned in the claims and the description can be important for the invention individually or in any combination. As long as the concept "can" is used in this application, it refers not only to technical feasibility but also to an actual technical implementation. Description of the Drawings
[0026] Embodiments are explained below with the aid of the drawings. In the drawings, it is schematically shown:
[0027] Figure 1 shows the various method steps of an exemplary method and
[0028] Figure 2 and 3 shows perspective views of an exemplary structural member in two views. Detailed Description
[0029] In an exemplary method for manufacturing a structural member 1, a central workpiece 10 including two finished regions 12, 14 is first provided. These finished regions 12, 14 are used to grip and position the central workpiece 10 in a manufacturing apparatus 100 for wire-based surfacing by means of two handling robots 110. Now, first and second member segments 20, 30 are produced on both sides of the central workpiece, thereby geometrically expanding the central workpiece 10. The first member segment 20 and the second member segment 30 are produced by means of wire-based surfacing. For this purpose, a linear material is melted and deposited in a predetermined path. The material is connected thereto in a material-locking manner to the central workpiece 10 or to the material layer located thereunder.
[0030] The first member segment 20 as well as the second member segment 30 thus each include a plurality of superimposed material layers or material coatings 21, 22, 23,... 31, 32, 33,.... In order to reduce thermal deformation in the member, it is particularly preferred that the material layers of the first member segment 20 and the material layers of the second member segment 30 are produced alternately in the method. For this purpose, the central workpiece 10 can be rotated, for example, by 180° after the formation of a material layer. Thus, the first member segment 20 and the second member segment 30 grow uniformly in height. Preferably, this remains the same at least for the first material layer, for example, the first 5 or 10 layers. Subsequently, the member segment is produced.
[0031] Figure 2 and 3 shows an exemplary structural member 1, which is manufactured by means of the method. The shown structural member 1 forms a tunnel reinforcement for a motor vehicle. A plate-shaped sheet body is used as the central workpiece 10, which already has a plurality of finished regions 12, 13, 14 in its edge region. In these regions, fastening points 16 in the form of through-holes are formed, which are used for a subsequent screwed connection of the structural member 1 to the vehicle. Screws in the through-holes have been shown by way of example. On a first side of the central workpiece 10, a first member segment 20 including two hollow bodies 26, 28 is formed, which extend substantially vertically from the central workpiece 10 into the space. On the opposite side, a second member segment 20 is formed in the intermediate region, which forms a reinforcing and strengthening structure.
[0032] List of reference signs
[0033] 1 Structural member
[0034] 10 Central workpiece
[0035] 12, 14 Machined areas
[0036] 16 Fixing points
[0037] 20 First member section
[0038] 21, 21, 22,... Material layers
[0039] 26, 28 Hollow bodies
[0040] 30 Second member section
[0041] 31, 32, 33,... Material layers
[0042] 100 Manufacturing equipment for wire-based surfacing
[0043] 110 Manipulating robot
Claims
1. A method for manufacturing a structural component (1), in particular for a motor vehicle, the method comprising the steps of: providing a central workpiece (10) comprising at least one finished area (12, 14); positioning the central workpiece (10) in a predetermined position in a manufacturing apparatus (100) for wire-based surfacing, using the finished area (12, 14); geometrically enlarging the central workpiece (10) on a first side of the central workpiece (10) with a first component section (20) and geometrically enlarging the central workpiece (10) on a second side of the central workpiece (10) with a second component section (30), the second side being opposite the first side; wherein the geometric enlargement of the central workpiece (10) is effected by layerwise application of material by wire-based surfacing.
2. The method according to claim 1, wherein the central workpiece (10) has its final geometric theoretical shape at the start of the method.
3. The method according to claim 1, wherein the central workpiece (10) has an initial shape deviating from the final geometric theoretical shape at the start of the method, the initial shape being determined such that the central workpiece (10) is transformed into the final geometric theoretical shape by thermal deformation occurring in the method.
4. The method according to any one of claims 1 to 3, wherein claddings (21, 22, 23,...) of the first component section (20) and claddings (31, 32, 33,...) of the second component section (30) are alternately produced.
5. The method according to any one of the preceding claims, wherein in order to position the central workpiece (10) at the start of the method, fastening points (16) are used, which are constructed in the finished area (12, 14) and are required on the finished structural component (1).
6. The method according to any one of the preceding claims, wherein the central workpiece (10) is made of sheet metal.
7. The method according to any one of the preceding claims, wherein the central workpiece (10) is configured as a plate-shaped body.
8. The method according to any one of the preceding claims, wherein the first and / or second component section (20) has a hollow body (26, 28).
9. A structural component (1), in particular manufactured by the method according to any one of claims 1 to 8, the structural component comprising: a central workpiece (10) having at least one exposed area (12, 13, 14); a first component section (20) attached to the central workpiece on a first side of the central workpiece (10); and a second component section (30) attached to the central workpiece on a second side of the central workpiece (10) opposite the first side, wherein the first and second component sections (20, 30) are manufactured by wire-based surfacing.