Method for manufacturing a component composite

Abstract

Method for producing a component composite from at least two components (1, 2), wherein - the at least two components (1, 2) are welded together in a fusion welding process, - a first component (1) with at least one overlap joint or parallel joint relative to a second component (2) is arranged such that the two components (1, 2) touch in at least one contact area (K1), and - in which at least one contact area (K1) is formed by a welded connection (S1) between the components (1, 2), - as a result of the creation of the weld joint (S1), heat is introduced into the first component (1) in such a way that previously directed residual stresses in it are released characterized by the fact that - by releasing the previously applied residual stresses, the first component (1) comes into contact with the second component (2) in at least one further contact area (K2, K3), and - after this application, another weld connection (S2, S3) is created in which at least one further contact area (K2, K3) is created between the components (1, 2).

Description

[0001] The invention relates to a method for producing a component composite according to the preamble of claim 1.

[0002] The GDR industrial patent DD 244 093 A1 relates to a method for reducing residual stress in rotationally symmetrical, prismatic, thick-walled tubular parts created by prior weld overlay on the circumference of these parts. The essence of the invention lies in applying additional weld layers to these residual-stress weld overlays and achieving a low-residual-stress state through the shrinkage of these additional weld layers in the area of ​​the actual weld overlay. The additional weld layers are generally removed.

[0003] Furthermore, DE 10 2020 207 603 A1 describes a method for manufacturing a bipolar plate with the following steps: - Providing two flat components that are stacked together, - joining the two flat components by welding in one joining plane, whereby residual stresses are mechanically introduced into one of the two flat components before the joining process, and - in addition to the mechanical introduction of residual stresses prior to the material-bonded joining, a temperature field is introduced into one of the two planar components, the introduction of the temperature field comprising heating the planar component in a seam area and being carried out by beam shaping of a welding laser or by using an additional laser.

[0004] DE 10 2021 207 884 A1 discloses a method for joining two plate-shaped components, in particular two monopolar plates for the production of a bipolar plate, in a media-tight manner, comprising the steps: - placing the first component on a surface of a clamping device, - placing the second component on the first component, - closing the clamping device, - placing a first weld on the second component, wherein a weld penetration depth is selected which is less than the material thickness of the second component, so that a kink forms along the first weld due to the weld distortion, over which the second component comes into line contact with the first component, - placing a joining weld on the first weld, so that the two components are welded together along the kink.

[0005] DE 10 2018 130 964 A discloses a method for joining two sheet metal components to manufacture an outer skin component for a motor vehicle, comprising the steps of: providing an outer sheet metal component with a visible outer surface and a flange angled relative to the outer surface, placing an inner sheet metal component with a free end onto the angled flange, and welding the outer sheet metal component and the inner sheet metal component together using a laser beam, characterized by the further steps of: determining an expected deformation area in the outer surface and generating a counter-pressure or counter-tension in the expected deformation area during welding.

[0006] The object of the present invention is to provide a novel method for producing a component composite.

[0007] The problem is solved according to the invention by a method which has the features specified in claim 1.

[0008] Advantageous embodiments of the invention are the subject of the dependent claims.

[0009] In a process for manufacturing a component composite from at least two components, the at least two components are welded together in a fusion welding process, wherein - a first component with at least one overlap or parallel joint is arranged relative to a second component in such a way that the two components touch in at least one contact area, and - in which at least one contact area is created by creating a welded connection between the components.

[0010] According to the invention, during the creation of the weld joint, heat is introduced into the first component in such a way that any residual stresses present in it are relieved and the first component aligns itself with the second component in at least one further contact area. Subsequently, after this alignment, a further weld joint is created in the at least one further contact area between the components.

[0011] When joining components using lap or parallel joint welding, a technically zero gap between the components is essential to ensure good joint quality. However, this requires very tight manufacturing tolerances in the individual component manufacturing processes, and consequently, high precision in the manufacturing tools and processes. This results in significant effort and high costs in implementing the manufacturing processes. Finally, the joining of the components also necessitates a complex clamping system, for example, in the form of various hold-down devices, to guarantee the zero gap.

[0012] The present method makes it particularly advantageous to create a zero gap during welding, even for components that deviate from a target shape due to manufacturing tolerances, by relieving residual stresses in the first component. This allows for the use of simpler and more cost-effective methods with larger manufacturing tolerances. Simultaneously, process reliability is increased by achieving a technically zero gap and, consequently, gap-free welding of the components. Furthermore, the creation of the weld joint eliminates the need for complex clamping of the components relative to each other. This eliminates the need for elaborate clamping technology, resulting in improved component accessibility and a reduction in the required equipment.The process can be implemented particularly well using fusion welding processes, such as electron beam welding and / or laser beam welding, since these methods allow for the precise application of energy to the components to relieve residual stresses. This process is especially suitable for use with metallic materials of the same or dissimilar composition. It is also particularly well-suited for thicker components with a thickness of ≥ 0.50 mm, such as those made of aluminum and / or steel. Various component joints can be produced using this process, such as radiator components for vehicles, body panels for vehicles, etc.

[0013] In one possible embodiment of the process, heat is introduced into the first component during the welding process, causing it to press against the second component in at least one additional contact area and exert a greater than zero pressing force on the second component in this contact area. Thus, by defined and targeted heating of the first component, residual stresses can be released or generated, resulting in the components being pressed together in at least one additional contact area.

[0014] Exemplary embodiments of the invention are explained in more detail below with reference to drawings.

[0015] This shows: Fig. 1 schematically illustrates the process of welding two components together and Fig. Figure 2 schematically shows a further sequence of a process for welding two components.

[0016] Corresponding parts are marked with the same reference symbols in all figures.

[0017] In Fig. Figure 1 shows a possible embodiment of a method for welding two components 1, 2.

[0018] Components 1 and 2 are each made of a metal, which may include steel and / or aluminum. Components 1 and 2 can be made of the same material or different materials. Specifically, components 1 and 2 are welded together to create a composite component, which may be, for example, part of a radiator component for vehicles, a body component for vehicles, or another vehicle component.

[0019] When joining components 1, 2 in an overlap joint or parallel joint by means of fusion welding, a technical zero gap must be present between components 1, 2 in the areas intended for welding in order to ensure good joining quality.

[0020] However, an upper first component 1 deviates from a target shape, for example due to manufacturing tolerances, which, when the first component 1 is placed on the second component 2, results in the first component 1 only resting on a support surface 2.1 to 2.3 of the second component 2.

[0021] In particular, the first component 1 has a thickness t of at least 0.5 mm and a maximum of 6.0 mm and is curved such that, at its end faces, it exhibits a height difference Δh of at least 0.025 mm and a maximum of 2.0 mm between its top surface and the center point of the top surface. This curvature indicates residual stresses within the first component 1. In one possible embodiment, the curvature can be intentionally introduced into the first component 1 during a manufacturing process, particularly a forming process, a stamping process, or another manufacturing process. For example, the curvature is created by overbending the first component 1.

[0022] To connect components 1 and 2, the first component 1 is initially placed onto the second component 2 in such a way that the latter rests on a central support surface 2.2 of the second component 2. This creates a contact area K1 between the first component 1 and the central support surface 2.2. At its end faces, the first component 1 has a distance to a further support surface 2.1, 2.3, which corresponds to the component height difference Δh of the first component 1.

[0023] After the first component 1 is placed onto the second component 2, a weld S1, for example a weld seam, is created between components 1 and 2 in the contact area K1 using a laser beam LS. This weld serves to pre-fix the first component 1 to the second component 2. During the creation of this weld S1, heat is introduced into the first component 1 by means of the laser beam LS. This heat leads to heat flows W1 and W2 within the first component 1, originating from the position of the weld S1. These heat flows W1 and W2 cause the residual stresses present in the first component 1 to be relieved. This results in a component deformation Δz of the first component 1, such that the first component 1, forming further contact areas K2 and K3, conforms to the contact areas 2.1 and 2.3 of the second component 2. The component deformation Δz depends on the height of the contact areas 2.1 and 2.3.In the illustrated embodiment, the component deformation Δz is at least as large as the component height difference Δh. In this embodiment, a component symmetry of the first component 1 is utilized so that it rests against the second component 2 on both sides, starting from the weld joint S1.

[0024] In particular, the system is configured such that the two components 1 and 2 lie flat and flush against each other in contact areas K1 to K3, creating a zero gap between them. Subsequently, a laser beam LS is used to create further welds S2 and S3 between the first component 1 and the bearing areas 2.1 and 2.3 of the second component 2 in the additional contact areas K2 and K3.

[0025] In one possible embodiment, it is provided that, as a result of the creation of the weld joint S1 using the laser beam LS, heat is introduced into the first component 1 such that the first component 1 aligns itself with the second component 2 in the further contact areas K2, K3 and exerts a pressing force greater than zero on the second component 2 in these further contact areas K2, K3. This can further improve the quality of the subsequent weld joints S2, S3.

[0026] Fig. Figure 2 shows a process of a possible further embodiment of a method for welding two components 1, 2.

[0027] Components 1 and 2 are each made of a metal, which may include steel and / or aluminum. Components 1 and 2 can be made of the same material or different materials. Specifically, components 1 and 2 are welded together to create a composite component, which may be, for example, part of a radiator component for vehicles, a body component for vehicles, or another vehicle component.

[0028] Unlike the one in Fig. In the exemplary embodiment of the method shown in Figure 1, the two components 1, 2 are connected to each other in such a way that they lie against each other over their entire surface.

[0029] However, the upper first component 1 deviates from a target shape, for example due to manufacturing tolerances, which, when the first component 1 is placed on the second component 2, results in the first component 1 only contacting the second component 2 at a contact surface K1.

[0030] In particular, the first component 1 has a thickness t of at least 0.5 mm and a maximum of 6.0 mm and is curved such that, at its end faces, it exhibits a height difference Δh of at least 0.025 mm and a maximum of 2.0 mm between its top surface and the center point of the top surface. This curvature indicates residual stresses within the first component 1. In one possible embodiment, the curvature can be intentionally introduced into the first component 1 during a manufacturing process, particularly a forming process, a stamping process, or another manufacturing process. For example, the curvature is created by overbending the first component 1.

[0031] To achieve full surface contact between the first component 1 and the second component 2 despite this shape deviation, the first component 1 is initially placed onto the second component 2 in such a way that a contact area K1 is formed between the two components 1 and 2 at an edge region of its underside facing one end face. Thus, a contact area K1 is formed between the first component 1 and the contact surface 2.1. At an opposite end face of the first component 1, there is a distance to the second component 2 that is at least twice the difference in component height Δh of the first component 1.

[0032] After the first component 1 is placed onto the second component 2, the first component 1 is pressed onto the second component 2 in the contact area K1 using a hold-down tool 3, and a weld S1 is created between components 1 and 2 by means of a laser beam LS. This weld serves to pre-fix the first component 1 to the second component 2. During the creation of this weld S1, heat is introduced into the first component 1 by means of the laser beam LS. This heat flow W1 leads to a heat flow within the first component 1, originating from the position of the weld S1. This heat flow W1 causes the residual stresses present in the first component 1 to be relieved.This results in a component deformation Δz of the first component 1 such that the first component 1, forming a further contact area K2, in particular over its entire surface, forming a parallel butt joint and a zero gap, contacts the second component 2. In the illustrated embodiment, the component deformation Δz is at least as large as twice the component height difference Δh.

[0033] Following this attachment of the first component 1 to the second component 2, a further weld connection S2 between the first component 1 and the second component 2 is created in the further contact area K2 by means of a laser beam LS.

[0034] In one possible embodiment, the laser beam LS is used to generate the weld joint S1 by introducing heat into the first component 1 such that the first component 1 aligns itself with the second component 2 in the further contact area K2 and exerts a greater than zero pressing force on the second component 2 in this further contact area K2. This further improves the quality of the subsequent weld joint S2.

Claims

[1] Method for producing a component composite from at least two components (1, 2), wherein - the at least two components (1, 2) are welded together in a fusion welding process, - a first component (1) with at least one overlap joint or parallel joint relative to a second component (2) is arranged such that the two components (1, 2) touch in at least one contact area (K1), and - in which at least one contact area (K1) is formed by a welded connection (S1) between the components (1, 2), - as a result of the creation of the weld joint (S1), heat is introduced into the first component (1) in such a way that previously directed residual stresses in it are released characterized by , that - by releasing the previously applied residual stresses, the first component (1) comes into contact with the second component (2) in at least one further contact area (K2, K3), and - after this application, another weld connection (S2, S3) is created in which at least one further contact area (K2, K3) is created between the components (1, 2). [2] Method according to claim 1, characterized by , that the residual stresses are directed into the first component (1) by means of a defined deformation. [3] Method according to claim 1 or 2, characterized by that the fusion welding process is carried out using at least one electron beam and / or laser beam (LS). [4] Method according to any one of the preceding claims, characterized by, that during the creation of the weld joint (S1) heat is introduced into the first component (1) such that the first component (1) contacts the second component (2) in at least one further contact area (K2, K3) and exerts a pressing force greater than zero on the second component (2) in at least one further contact area (K2, K3).

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