Methods for the material-bonded joining of components

Abstract

The invention relates to a method for the material-bonded joining of components (105, 110), comprising the steps (1000) Provide - of a first component (105), - a second component (110), and - a segmented compound foil (135) containing metallic materials which react exothermically when activated, (2000) Arranging the connecting foil (135) on the second component (110) such that the connecting foil (135) has at least two segments (200, 205) which are arranged parallel and / or at an angle to each other, (3000) Placing the connecting foil (135) on the first component (105) so that the connecting foil (135) is positioned between the first and second components (105, 110), and (4000) Activating the metallic materials of the connecting foil (135) via an activating agent (405), wherein the connecting foil (135) is heated such that a metallurgical bond is created between the first component (105) and the second component (110). Furthermore, the invention relates to an arrangement (100) of a second component (110) on a first component (105), wherein the second component (110) has been connected to the first component (105) by such a method.

Description

[0001] The invention relates to a connection between a first component and a second component. In this context, a method for the material-bonded connection of two components and an arrangement of a second component on the first component are particularly claimed. The invention is especially suitable for applications in which the first component is a measuring object, for example a shaft, an axle, or the like, and the second component is designed as a sensor arrangement, in particular comprising a strain gauge.

[0002] German patent DE 10 2021 208 761 A1 discloses a method for connecting a sensor chip to a measurement object. According to this patent, a measurement object, a sensor chip, and a connecting film are provided, the connecting film containing metallic materials that react exothermically upon activation. The connecting film is then placed between the sensor chip and the measurement object. The metallic materials of the connecting film are then activated, causing the connecting film to heat up sufficiently to create a metallurgical bond between the sensor chip and the measurement object.

[0003] The object of the present invention is to provide a method for the material-bonded connection between a first component and a second component, which is flexibly applicable and which also makes it possible to selectively transmit forces and / or strains between the components. The invention achieves this object by means of the subject matter of the independent claims. Dependent claims describe preferred embodiments.

[0004] The present invention proposes a reactive foil soldering process for obtaining a bond, particularly an intermetallic one, between two components. The joining process is based on the use of a bonding foil or reactive multilayer foil as a local heat source. The foil consists of a novel class of nanotechnology material in which self-propagating exothermic reactions can be triggered at room temperature by an ignition process. By inserting such a foil between two components, the heat generated by the reaction in the foil melts the foil as well as any other materials or layers optionally arranged on it, such as a solder layer or adhesion promoter layer, so that the bond is completed at room temperature in approximately one second. The heat induced during the reaction is very low due to the rapid reaction rate (e.g., 10 m / s) and the small material thickness (e.g., <100 µm).

[0005] In this sense, a method for the material-bonded joining of components is proposed according to a first aspect of the invention. In a first step, a first component, a second component, and a segmented bonding film containing metallic materials that react exothermically upon activation are provided. In a second step, the bonding film is arranged on the second component such that the bonding film has at least two segments that are arranged parallel and / or at an angle to each other. In a third step, the bonding film is placed on the first component so that the bonding film is positioned between the first and second components.In a fourth step, the metallic materials of the bonding foil are activated by an activating agent, causing the foil to heat up to such an extent that a metallurgical bond is created between the first and second components. The structured bonding foil can improve the flexibility and / or selective strain transfer between the components.

[0006] The first component can be a measurement object or target, for example, a shaft, an axle, or the like. The second or third component can be a sensor assembly, in particular a sensor chip or strain gauge. The first component can serve as a carrier for the other components. A sensor chip is designed to detect a physical property of the measurement object. A strain gauge is designed to detect tensile and compressive deformations of the measurement object or the first component.

[0007] A segmented bonding film is a non-full-surface reactive multilayer system (RMS) that, in its unactivated state, comprises several segments and, optionally, connecting sections linking the segments together. Upon activation, the RMS creates an effective, metallurgical bond between the two components in the segmented region, while simultaneously achieving optimized force and / or strain transmission behavior. The segmented bonding film is produced by vapor deposition of thousands of alternating nanoscale layers of aluminum and nickel. In the second step of the process, the materials can be vapor-deposited onto the second component. Preferably, the bonding film is applied to the second component using a mask in this second step.In other words, the segments of the bonding film are arranged by vapor deposition or sputtering of the metallic materials through the mask. This ensures that the reactive multilayer system, and in particular the aforementioned bonding film segments, are positioned only at predefined locations on the second component. The mask acts as a template, defining and subdividing areas on the first and / or second component. Specifically, it defines the first area, where an RMS layer or segments and any bonding sections are to be placed, and the second area, where no RMS layer, segments, or bonding sections are to be placed. The mask thus allows for the shading of specific sections or areas. This enables the precise fabrication of a bonding film segment structure while simultaneously saving material.The bonding film thus achieves an interruption and / or structuring of the reactive layer. This can be used to advantage for the material-bonded connection, either thermally and / or mechanically.

[0008] The connecting film can be activated by a small pulse of local energy from electrical, optical or thermal sources, causing the segments and any connecting sections of the connecting film to react exothermically in order to generate precise local heat up to temperatures of 1500 °C in fractions of a second, which spreads at a high speed of, for example, up to 8 m / s with low heat input into the environment.

[0009] The segments of the bonding foil are RMS structures which, upon activation of the metallic materials of the bonding foil, create a metallurgical bond between the two components. The segments can intersect or be connected to each other via at least one connecting section.

[0010] The term "arranging the bonding film on the second component" means that the bonding film is first attached or applied to the second component, creating a separately manageable component. This component is then placed on the first component in the third step and bonded to it in the fourth step. Thus, in the second step, the bonding film and the second component form a separately manageable component, resulting in the second component with a directly integrated bonding film or directly integrated RMS.

[0011] The segments of the bonding film are shaped and connected in such a way that, after the fourth step, a rapidly formed and effective metallurgical bond exists between the two components. The propagation of the exothermic reaction front can be precisely controlled by structuring the segments of the bonding film. For example, the segments of the bonding film can be arranged in a meandering pattern, thus guiding the reaction front in a meandering direction. In this case, the segments are essentially arranged parallel to each other and connected via curved sections. The segments are dimensioned such that, after activation of the bonding film, effective bonding layers exist between the two components in the areas where the segments were arranged.

[0012] The proposed method creates a strong adhesive surface to bond the second component, or the separately handled component, to the first component in a single step. The bond between the first and second components is initiated and created using a single activator or ignition source. Thus, the bond is formed in a single activation step.

[0013] The segments of the bonding film are arranged relative to each other and, if necessary, connected with connecting sections and geometrically designed in such a way that, similar to controlled explosions, a precisely defined activation sequence is maintained, so that after the fourth step an effective material bond exists between the first and second components.

[0014] In the fourth step, or activation step, the material of the first component and / or the second component is / are locally melted or partially melted, so that a direct connection is made.

[0015] The respective segment of the bonding foil, positioned between the first and second components, is considered a joining section that forms a bonding layer between the two components after the fourth step. Depending on the arrangement of the segments on the second component, several bonding layers may exist between the components after the fourth step. One or more of the segments can be designed as an activation section or segment, or as a reactive part of the bonding foil. The activating agent is applied to a defined location within the respective segment to initially activate the metallic material of the bonding foil in the fourth step. The reactive part of the bonding foil is only required to provide or conduct energy to activate the bonding section.The activating agent provides sufficient activation energy to melt the connecting foil.

[0016] The activation of the metallic materials of the connecting foil can be achieved, for example, by ignition using the activating agent. The process requires no special heat, vacuum, or gas atmosphere. The connecting foil can be ignited, for example, with a standard 9V battery connected to the connecting foil via the activating agent. The activating agent can comprise wires, such as a positive and a negative terminal, with a potential difference between the terminals. The wires can be separate and handled independently. Alternatively, the two wires can be joined at their ends to form a type of connector, in order to maintain a defined distance between the wires. The activating agent can also be or comprise a voltage source, particularly a battery, or a heating probe.

[0017] During the process, no high pressures or temperatures need to be applied to the components. High electromagnetic fields are also unnecessary. The metallic bonding layer between the components, created by activating the metallic materials of the bonding foil, exhibits particularly high dimensional stability as well as high thermal and electrical conductivity. Furthermore, the manufacturing or bonding process is simplified, enabling particularly cost-effective production.

[0018] The inventive method is characterized by lower temperatures and stresses during joining. These lower stresses induce fewer prestresses in the components. Furthermore, the low temperatures and low pressure allow the use of different materials, such as polymers. The bond between the components produced by the inventive method does not age over time or with temperature changes. Steam, pressure, or similar factors do not alter the parameters of the bond. The composite material is particularly resistant to moisture, chemicals, high / low temperatures, and rapid temperature changes. Therefore, the bond does not change its parameters, especially due to temperature, humidity, pressure, or similar factors. The composite material also offers elastic deformation for repeatability.

[0019] Advantageously, the electrical connection between the activating agent and the connecting film can be made with the same device used to place the second component with the connecting film attached to it onto the first component and to apply the pressure for a material-bonded connection.

[0020] The bonding foil, especially its segments and other optional sections, can be manufactured with exceptional precision and efficiency using laser cutting to the desired dimensions. The structure and geometry of the bonding foil can be created, for example, after its placement on the second component. Laser cutting is performed primarily before this third step. This allows for virtually any desired structuring of the bonding foil to improve the properties of the material-bonded connection.

[0021] To prevent unpredictable deformation of the bond between the first and second components, a fixing pad can be applied to the layers with low pressure. In this respect, a fixing pad exerting pressure on the first and / or second component is preferably used to counteract deformation of the bonding foil and optional solder layers during activation and metallurgical bonding in the fourth step. The pressure is so low that it does not lead to any stresses within the components that could impair the strength of the bond or the measurement accuracy.

[0022] In one embodiment, the connecting film comprises a first segment and a second segment, which are connected to each other via at least one connecting section. The connecting section is designed and configured to transfer exothermic reaction energy from the first segment to the second segment when the metallic materials of the connecting film are activated. The connecting section is, for example, a cross-connection between two adjacent segments, which, during the activation of the metallic materials of the connecting film, is solely intended for the transmission of the exothermic reaction wave. A segment differs from a connecting section in its function during and after the activation of the connecting film.During activation, the segments and connecting sections are activated to create the material bond between the first and second components. Each segment becomes part of a bonding layer between the two components, thereby enabling torque or force transmission between them. Although the connecting sections are located on the second component, they do not form a material bond between the first and second components during or after activation of the bonding film. Therefore, after activation of the bonding film and the resulting material bond between the two components, no forces and / or strains are transmitted via the respective activated connecting section, but exclusively via the bonding layers formed by the activated segments between the first and second components.

[0023] The segments can be linear. "Linear" means that the respective segment is designed in the form of a straight line, i.e., essentially uncurved. A linear design of the respective segment can be advantageous if the segments or the connecting layers are to be aligned in the direction of a force to be detected by a sensor arrangement after the fourth step. At least one of the segments can alternatively or additionally be curved.

[0024] A segment is preferably compact in shape, such that the ratio of its area to the length of its outline is as small as possible. For example, a segment can have the shape of a circle, a rhombus, a rectangle, or a regular polygon. A segment can also be elongated, i.e., a strip. After activation of the bonding film, the previously existing segment becomes part of the bonding layer, creating a material-bonded connection between the first and second components.

[0025] A connecting section is preferably elongated. A connecting section preferably has a first and a second end, each of which may adjoin a segment. Between the ends, the connecting section typically extends straight or curved. The width of the connecting section may be less than its length. The connecting section is designed to ensure the reliable transfer of reaction energy. The connecting section has a corresponding minimum height and / or minimum width, i.e., a predetermined minimum cross-sectional area.

[0026] In some embodiments, a connecting section has more than two ends, allowing it to connect more than two segments. In the case of three ends, the connecting section can, for example, be Y-shaped. In yet another embodiment, one connecting section adjoins another. For instance, a straight connecting section can be provided, to which a series of further connecting sections adjoin on the right and / or left, each of which can lead to a segment. This allows for a distribution of the reaction energy upon activation of the connecting film.

[0027] The connecting section is thus to be understood as a reaction section of the connecting film, which links at least two segments of the connecting film together before the fourth step. The shape, geometry, and structure of each connecting section are chosen such that the activation step occurs as quickly and effectively as possible. It is conceivable that at least two adjacent segments are connected to each other via two or more connecting sections, so that activation of the respective segment can occur at several points simultaneously. Connecting sections between segments of the connecting film are advantageous if all segments are to be interconnected so that initial activation of the connecting film can be achieved by a single activating agent.The reaction of the metallic material of the connecting foil spreads along the segments, activating the metallic material to create the metallurgical bond between the two components.

[0028] In its simplest form, the connecting film has a substantially constant thickness. In other words, the segments and the optional activation section have the same thickness. It is conceivable, for example, that the connecting section of the film has a first layer thickness, and at least one of the segments has a second layer thickness that differs from the first. In other words, the connecting film can be designed with variable thickness. Preferably, each connecting section of the film is thinner than the segments of the film. This allows for material savings in the connecting film, as each connecting section is designed to be just thick enough to transfer sufficient activation energy from one segment to the next.Accordingly, it can be advantageous to make each connecting section many times narrower than the segments. Conversely, each segment can be thicker to provide sufficient energy for the exothermic reaction of the metallic material of the connecting foil during activation in the fourth step.

[0029] Everything said here regarding the first and second segments also applies, of course, to further segments of the connecting foil. Therefore, the connecting foil preferably comprises more than two segments. All segments can be arranged parallel to each other. Alternatively, some of the segments can be arranged parallel to each other, and others at an angle to each other. In one embodiment, the segments are arranged parallel to each other, with the respective connecting section between the two segments positioned perpendicular to them. Thus, a right-angled arrangement of segments and connecting sections can be achieved. This allows for a kind of checkerboard pattern, with spaces or recesses without metallic material in the connecting foil between the segments and connecting sections.Thus, when the connecting foil is arranged on the second component, the segments and / or connecting sections enclose at least one free space or recess. In one embodiment, a regular arrangement of recesses is provided on the connecting foil, which divides the metallic materials of the connecting foil into segments and, optionally, connecting sections.

[0030] In one embodiment, the connecting foil comprises a first segment and a second segment that intersect at a point of intersection. In contrast to the previous example, connecting sections can be omitted in such a connecting foil, since the segments overlap at the point of intersection. This allows for the creation of a network-like segment structure with intersecting segments, where several segments of the same orientation are arranged parallel to one another. Preferably, a second segment is arranged at an angle between 0° and 90° to a first segment.

[0031] In another embodiment, the connecting film comprises a segmented structure with a network of ring-shaped segments. Preferably, the segments are hexagonal and have linear sections that, in their extent around the corresponding surface area, form a hexagon, such that the sections each form the edges of the hexagons. Preferably, the network of ring-shaped segments is configured as a honeycomb structure. In this case, adjacent hexagons are abutting each other, so that, in this example as well, no connecting sections are required. However, hexagonal segments can also be spaced apart from each other and connected by at least one connecting section.

[0032] Preferably, the second component is configured as a sensor assembly comprising a strain gauge with conductive tracks. In the second step, the bonding film is arranged on the second component such that, after the third step, the first segment is positioned between the first component and a first conductive track of the strain gauge, and the second segment is positioned between the first component and a second conductive track of the strain gauge or an electronic component. Thus, the bonding film can be used for the metallurgical bonding of a sensor to the first component and, optionally, for the metallurgical bonding of an electronic component to the first component. The segmentation of the bonding film can therefore be used for the functional integration of strain gauges and evaluation electronics on a common substrate, for example, a PI film or the like.The segments of the connecting film are designed, aligned and arranged relative to each other in such a way that the component strain is optimally transferred to the strain gauge, in particular without negatively affecting the function of the evaluation electronics.

[0033] A strain gauge (or strain gauge) is designed to measure strain, compression, and / or torque generated by, emanating from, or transmitted by the first component. The strain gauge preferably comprises a carrier layer facing the first component and the connecting film, as well as a measuring grid of conductive traces. The strain gauge is preferably a foil strain gauge, meaning that the measuring grid, made of resistance wire preferably 3 to 5, preferably up to 8 µm thick, is laminated onto a thin polymer-based plastic substrate and etched, and provided with electrical connections that enable electronic communication with the electronic module.

[0034] Additionally, the measuring grid can be covered by a protective layer that is bonded, in particular glued, to the carrier layer and provides mechanical protection for the measuring grid. The protective layer can be omitted if the strain gauge is encapsulated in a housing. Multiple measuring grids can also be arranged on the carrier layer. Advantageously, the carrier layer and / or the protective layer is in the form of a film. Thus, the carrier layer is preferably a carrier film and / or the protective layer a protective film. The carrier layer is preferably made of polyimide. If a protective layer is provided, it can also be made of polyimide.

[0035] In cases where the segments are connected via connecting sections or reaction sections, the respective connecting section is arranged without contact points with the conductor tracks and / or the electronic component of the sensor assembly. Accordingly, the metallurgical bond is generated exclusively at the precisely positioned segments, whereas the connecting sections are solely intended for the transmission of activation energy.

[0036] The strain gauge with the structured connecting film is flexible in its application because the individual RMS segments do not need to bend as much, and the bending can be shifted to the spaces between the segments. As soon as the strain gauge is applied to a surface that is not perfectly flat, the probability of the connecting film being unexpectedly damaged, especially breaking, is low.

[0037] By applying the metal layers of the bonding film to a partial surface using the aforementioned mask, it is possible to selectively transfer strains after the material bond has been established. The deformation of the first component is primarily transferred to the sensor arrangement, particularly the strain gauges, via the bonding layers or the activated segments of the bonding film. It is conceivable to use multiple strain gauges, which could, for example, be arranged in a superimposed configuration.

[0038] Preferably, the activation agent is attached to the connecting foil at two or more activation positions. For example, the sensor arrangement or strain gauge can be designed such that the connecting foil can be activated at one or more activation positions. These activation positions can be, for example, a hole, a thinning of the strain gauge carrier foil, or a gap between strain gauge conductor tracks. At these positions, as already described, a small pulse of local energy from electrical, optical, or thermal sources can be introduced to activate the connecting foil. For example, a laser can be used to trigger the activation from above through the strain gauge. Alternatively, an electric current can be used to trigger the activation from above. In both variants, either a hole can be pre-made or the strain gauge carrier foil can be pierced.The activation position influences the reaction of the bonding foil and the associated bond quality.

[0039] It is conceivable to provide all activation positions only on the first segment, with the activation of the connecting foil originating from the first segment. Furthermore, it is conceivable to initiate activation simultaneously on several segments. The activation paths can be combined or remain separate, allowing for the realization of multiple connection layers. Additionally, it is conceivable to connect the activation means to an activation section of the connecting foil, where the activation section is at least indirectly connected to one or more segments.

[0040] In the second step, the interconnecting foil can be arranged or bonded to a first solder layer on the second component. In the third step, the interconnecting foil can be positioned on the first component such that it is located between the second component, and optionally a first solder layer, and a second solder layer. Accordingly, the aforementioned solder layer is arranged, provided, or applied to a side or surface of the respective component facing the interconnecting foil. This surface is, in particular, a flat surface.

[0041] In one embodiment, the surfaces of the first and / or second component can be curved. In this case, the connecting film preferably has a shape complementary to the outer geometry of the first and / or second component. If the second component comprises a sensor arrangement with a strain gauge, the sensor arrangement or the strain gauge can be pre-shaped before the metal layers are applied to the second component, particularly the strain gauge's carrier film. For example, the strain gauge, including the carrier film (and optionally the metallization), can be pre-curved slightly so that it already has the curvature of a first component, such as a shaft, when used later. Since the RMS layer structure of the connecting film is relatively brittle, the pre-defined curvature prevents unwanted, premature breakage of the connecting film.

[0042] According to a second aspect of the invention, an arrangement of a connecting film is provided on a second component, wherein the connecting film has at least two segments that are arranged parallel and / or at an angle to each other. In other cases, the arrangement is designed as a separately handleable component that can, in principle, be stored for any length of time and can be connected to a variety of different first components in a subsequent step. Such an arrangement is, for example, a sensor arrangement with an integrated connecting film.

[0043] According to a third aspect of the invention, an arrangement of a second component is provided on a first component, wherein the second component has been joined to the first component by a method according to the above descriptions. The arrangement can be manufactured in a single joining process. Alternatively, the second component, together with the connecting film arranged thereon, can be materially bonded to the first component as a separately handleable component according to the second aspect of the invention. The first component can be a measuring object, in particular a carrier, a shaft, an axle for an engine or transmission of a motor vehicle, or a robot arm segment for a robot, or the like, and the second component can be a sensor arrangement. The sensor arrangement is configured to detect a physical property of the measuring object.If the sensor arrangement includes one or more strain gauges, then the sensor arrangement is configured to detect tensile and compressive deformations of the first component. The sensor arrangement is therefore configured to measure a deformation, strain, force, and / or torque generated or transmitted by the first component.

[0044] Where elements are designated by means of a number, for example "first component," "second component," "first segment," and "second segment," this numbering or designation is solely for differentiation purposes and does not imply any dependency between the elements or a mandatory sequence. This means, for example, that the connecting foil does not need to have a "second segment" to be able to have a "third segment," and vice versa. The connecting foil can also include a "third segment" and a "fourth segment" without necessarily having a "second segment."

[0045] The invention will now be described in more detail with reference to the attached figures, in which: Fig. 1 a view of an arrangement according to the invention of a first component on a second component according to a first embodiment; Fig. 2 a longitudinal sectional view of a section of the arrangement according to the invention Fig. 1 to illustrate a layer structure; Fig. 3 a top view of the section of the arrangement according to the invention Fig. 1 and Fig. 2; Fig. 4 an exploded view of layers and tools for joining a first component to a second component using a connecting film (left) and the arrangement resulting from the joining (right); Fig. 5 a block diagram to illustrate a process of a method according to the invention for connecting the first component with the second component; Fig. 6 A greatly enlarged cross-sectional view of the connecting foil for the arrangement according to Fig. 1 to Fig. 4; Fig. 7 a top view of a strain gauge of the second component and of a connecting foil arranged thereon for connecting the first component to the second component according to the preferred embodiment according to Fig. 1 to Fig. 6; Fig. 8 a top view of the connecting foil for connecting the first component to the second component according to a first embodiment alternative; and Fig. 9 a top view of the connecting foil for connecting the first component with the second component according to a second design alternative; represents, where identical or similar elements are provided with the same reference symbol.

[0046] The Fig. Figures 1 to 4 show an arrangement 100 in which a first component 105, serving as the measurement object, is materially bonded to a second component 110, serving as the sensor arrangement. The sensor arrangement includes a strain gauge 115, which is configured to detect tensile and compressive deformations of the first component. The strain gauge 115 comprises, according to Fig. 1 in conjunction with Fig. 7 a carrier film 120 and a measuring grid with several conductor tracks 125, 128, 130, which according to Fig. 7 are connected to each other via deflection sections 700, connected in series and arranged in a meandering pattern on the carrier film 120.

[0047] The second component 110 is manufactured using a process that takes into account Fig. As described in more detail in section 4, the first component 105 is materially bonded. The first component 105 is significantly larger than the second component 110.

[0048] After Fig. 1 to Fig. Figure 4, left, shows a state of the arrangement 100 before the metallurgical bond between the first component 105 and the second component 110 is created. A segmented connecting foil 135 is provided to create a strong, at least metallurgical, bond between the first component 105 and the second component 110. The connecting foil 135 is a so-called NanoFoil®, i.e., a reactive multilayer foil (RMS for short), which is produced by vapor deposition of thousands of alternating nanoscale layers of aluminum 600 and nickel 605. A highly magnified cross-sectional view of the connecting foil 135 with the aluminum and nickel layers 600 and 605 is shown in Figure 4. Fig. Figure 6 shows that when the bonding foil 135 is activated by a small pulse of local energy from electrical, optical, or thermal sources, it reacts exothermically to generate precise local heat up to temperatures of 1500 °C in fractions of a second. The aluminum and nickel layers 600 and 605 are to be understood as the metallic materials of the bonding foil 135 within the meaning of the invention.

[0049] In a first process step 1000 of the process according to the invention, which is in Fig. As illustrated in Figure 5 as a block diagram, components 105, 110 and the connecting foil 135 are first provided. In a second process step 2000, the connecting foil 135 is applied to the second component 110 by means of a mask (not shown here) by vapor deposition of the metallic materials. After being applied to the second component 110, the connecting foil 135 has several linear segments 200, 205, 210, which can be arranged parallel and / or at an angle to each other, depending on the requirements. In the first embodiment, the segments 200, 205, 210 are arranged parallel to each other, and according to Fig. 7. Two adjacent segments 200, 205, 210 are connected to each other via several uniformly spaced connecting sections 705 in the form of narrow, rib-like reaction sections. The connecting sections 705 are provided for the transfer of reaction energy between the segments 200, 205 and 205, 210, respectively, and can therefore be many times narrower than the segments 200, 205, 210, as is also shown here. The connecting sections 705 run essentially perpendicular to the segments 200, 205, 210. Spaces 215 are provided between the segments 200, 205, 210 and the connecting sections 705, in which no metallic materials are present. Fig. 6 are arranged.

[0050] After the second process step 2000, a separately handleable component 220 is available, consisting of the connecting foil 135 and the second component 105. This component 220 is in Fig. 2 and Fig. 3 indicated by the dashed rectangle around the connecting foil 135 and the second component 105.

[0051] The connecting foil 135 is, as in Fig. As shown in more detail in Figure 7, the second component 110 is arranged such that the first segment 200 of the connecting foil 135 is located below the first conductor track 125 of the strain gauge 115, the second segment 205 of the connecting foil 135 is located below the second conductor track 128 of the strain gauge 115, and the third segment 210 of the connecting foil 135 is located below the third conductor track 130 of the strain gauge 115, and so on. Alternatively or additionally, one of the segments can be located below an optional electronic component of the sensor assembly. The segments 200, 205, 210 are applied in the measuring direction of the strain gauge 115, with the connecting sections 705 between the segments 200, 205, 210 arranged transversely to it.

[0052] In a third process step 3000, the connecting foil 135 is placed on the first component 105, so that the connecting foil 135 is arranged between the first and second components 105 and 110. After process step 3000, the first segment 200 is arranged between the first component 105 and the first conductor track 125 of the strain gauge 115, the second segment 205 is arranged between the first component 105 and the second conductor track 128 of the strain gauge 115, and the third segment 210 is arranged between the first component 105 and the third conductor track 130 of the strain gauge 115, and so on. The connecting sections 705 are arranged free of contact points with the conductor tracks 125, 128, 130 and / or the optional electronic component of the sensor arrangement, as these are only intended for energy transmission between the segments 200, 205, 210.

[0053] The connecting foil 135 is after Fig. 4 connected via a wire 400 to an activation agent 405 in the form of a battery 410, wherein the battery 410 or the wire 400, in particular a positive terminal and a negative terminal of the wire 400, according to Fig. Component 220 is connected to the connecting foil 135 at two activation points 300 and 305. The activation points 300 and 305 are arranged symmetrically around a longitudinal and transverse axis of component 220. The position of the activation points 300 and 305 influences the reaction of the connecting foil 135 and the resulting quality of the material-bonded connection between components 105 and 110 after an activation process of the connecting foil 135.

[0054] The battery 410, acting as an ignition source, provides electrical current to activate the metallic materials of the connecting foil 135 in a fourth process step 4000. When the activation agent 405 is activated, the current is introduced into the connecting foil 135, for example, the first segment 200 of the connecting foil, via the wire 400 and the activation points 300, 305. The segments 200, 205, 210 can be connected in series and / or parallel, so that when the metallic material in the segments 200, 205, 210 and the connecting sections 705 of the connecting foil 135 is activated by the battery 410, a kind of chain reaction is triggered, which successively activates all segments 200, 205, 210 of the connecting foil 135. In this sense, in process step 4000 the metallic materials of the connecting foil 135 are activated via the activating agent 405, so that the connecting foil 135 orThe segments 200, 205, 210 and the connecting sections 705 are heated such that a metallurgical bond is created in the areas of segments 200, 205, 210 between the first component 105 or a surface 140 of the first component 105 and the second component 110 or the carrier film 120 of the sensor arrangement. Since the reaction rate of the connecting film 135 is approximately 10 m / s due to its small thickness, the activation and the associated metallurgical bond between the first component 105 and the second component 110 are perceived as a simultaneous process.

[0055] In the left part of the Fig. Figure 4 shows a state in which no material bond has yet been created between the first component 105 and the second component 110. The right part of the Fig. Figure 4 shows the state after the formation of the material-bonded connection between the two components 105 and 110 to realize the arrangement 100. After process step 3000, all layers are located in the Fig. The four components are stacked on top of each other in the sequence shown on the left. A fixing pad 415 exerts a pressure p on the stack formed by the first component 105, the bonding film 135, and the second component 110 via a compliant layer 420 at the beginning of process step 4000, or before. The pressure p is very low and acts perpendicularly on the top surface of the second component 110. The pressure p serves to counteract deformation of the bonding film 135 during activation in the fourth process step 4000. Activation creates a stable bonding layer 425 between the first component 105 and the second component 110, cf. Fig. 4, right.

[0056] Depending on the design of the second component 110, the segments 200, 205, 210 can alternatively be arranged rotated by 90°, so that the segments 200, 205, 210 are arranged vertically and spaced apart, with the narrow connecting sections 700 connecting the segments 200, 205, 210 horizontally to each other.

[0057] The segments 200, 205, 210 of the connecting foil 135 are in a further embodiment according to Fig. 8 arranged at an angle to each other such that any two of the segments 200, 205, 210 intersect at a crossing point 800. After Fig. Figure 8 shows several first segments 200 arranged horizontally and parallel to each other, with several second segments 205 arranged at an angle of +45° relative to them and also parallel to each other. Several third segments 210 are arranged at an angle of -45° to the first segments 200 and also parallel to each other. Such an arrangement of the segments 200, 205, 210 is particularly advantageous when several superimposed strain gauges 115 are rotated 45° clockwise and counterclockwise. Furthermore, such a connection can be used flexibly, i.e., for different applications.

[0058] According to a further embodiment according Fig.The connecting foil 135 comprises a segment structure 900 with a network of ring-like segments 200, 205, 210, wherein the segment structure 900 is designed as a honeycomb structure. Thus, the segments 200, 205, 210 are hexagonal segments 200, 205, 210. The network of hexagonal segments 200, 205, 210 has a plurality of hexagons, with each adjacent hexagon forming a common hexagonal edge. Each hexagon therefore has an edge that simultaneously forms the edge of another adjacent hexagon. The hexagons are of the same size or have a substantially identical enclosed surface area or free space 905.

[0059] It is of course conceivable to adapt the shape of the connecting film 135 to an external geometry of the first and / or second component 105, 110, in particular the surface 140 and the carrier film 120. The strain gauge 115, including the carrier film 120, can be curved before the connecting film 135 is attached to it in process step 2000. Furthermore, it is conceivable to provide two or more strain gauges in the sensor arrangement. Reference sign p print 100 arrangement 105 First component 110 Second component 115 strain gauges 120 Carrier film of the strain gauge 125 First conductor track of the strain gauge 128 Second conductor track of the strain gauge 130 Third conductor track of the strain gauge 135 Connecting foil 140 Surface area of ​​the first component 200 First segment of the connecting foil 205 Second segment of the connecting foil 210 Third segment of the connecting foil 215 free space 220 component 300 First activation position 305 Second activation position 400 battery 405 Activating Agents 410 wire 415 Fixing pad 420 compliant layer 425 Compound layer 600 aluminum layer 605 Nickel layer 700 Deflection section 705 Connecting section 800 Intersection point 900 Segment structure 905 free space 1000 process step 2000 process step 3000 process step 4000 process step QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 208 761 A1

[0002]

Claims

[1] Method for joining components with a material bond (105, 110), comprising the steps (1000) Provide - of a first component (105), - a second component (110), and - a segmented compound foil (135) containing metallic materials which react exothermically when activated, (2000) Arranging the connecting foil (135) on the second component (110) such that the connecting foil (135) has at least two segments (200, 205) which are arranged parallel and / or at an angle to each other, (3000) Placing the connecting foil (135) on the first component (105) so that the connecting foil (135) is positioned between the first and second components (105, 110), and (4000) Activating the metallic materials of the connecting foil (135) via an activating agent (405), wherein the connecting foil (135) is heated in such a way that a metallurgical bond is created between the first component (105) and the second component (110). [2] Method according to claim 1, wherein the connecting foil (135) comprises a first segment (200) and a second segment (205) which are connected to each other via at least one connecting section (705), wherein the connecting section (705) is designed and configured to transfer exothermic reaction energy from the first segment (200) to the second segment (205) when the metallic materials of the connecting foil (135) are activated. [3] Method according to claim 2, wherein the segments (200, 205) are arranged parallel to each other, wherein the connecting section (705) is arranged between the two segments (200, 205) and perpendicular to them. [4] Method according to claim 2 or claim 3, wherein the connecting section (705) is many times narrower than the respective segment (200, 205). [5] Method according to claim 1, wherein the connecting foil (135) comprises a first segment (200) and a second segment (205) which intersect at a crossing point (800). [6] Method according to claim 1, wherein the connecting foil (135) comprises a segment structure (900) with a network of ring-shaped segments (200, 205). [7] Method according to claim 6, wherein the network of ring-like segments (200, 205) is designed as a honeycomb structure. [8] Method according to one of the preceding claims, wherein the bonding film (135) is applied to the second component (110) in step (2000) by means of a mask. [9] Method according to one of the preceding claims, wherein in step (2000) a separately manageable component (220) is formed from the connecting film (135) and the second component (110). [10] Method according to one of the preceding claims, wherein the second component (110) is designed as a sensor arrangement comprising a strain gauge (115) with conductor tracks (125, 128), wherein in step (2000) the connecting film (135) is arranged on the second component (110) such that after step (3000) the first segment (200) is arranged between the first component (105) and a first conductor track (125) of the strain gauge (115) and the second segment (205) is arranged between the first component (105) and a second conductor track (128) of the strain gauge (115) or an electronic component. [11] Method according to claim 10 in conjunction with one of claims 2 to 4, wherein the connecting section (705) is arranged free of contact points with the conductor tracks (125, 130) and / or the electronic component of the sensor arrangement. [12] Method according to one of the preceding claims, wherein the activation means (405) is attached to the connecting foil (135) at two or more activation positions (300, 305). [13] Method according to one of the preceding claims, wherein the connecting foil (135) has a shape complementary to the outer geometry of the first and / or second component (105, 110). [14] Arrangement (100) of a connecting film (135) on a second component (110), wherein the connecting film (135) has at least two segments (200, 205) which are arranged parallel and / or at an angle to each other. [15] Arrangement (100) of a second component (110) on a first component (105), wherein the second component (110) has been connected to the first component (105) by a method according to any one of claims 1 to 13.

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