DE102023125365A1 - Method for determining the condition of a joint and hybrid component with a joint - Google Patents

Abstract

Method for determining the condition of a joint with the following steps:
a) providing a first component (1) with a first joining surface (11) and a second component (2) with a second joining surface (21),
b) forming a marker structure (110) with at least two different element types (111, 112), wherein each of the different element types (111, 112) comprises a plurality of individual elements (3), which are each formed over at least a surface portion of the first joining surface (11) of the first component (1), and wherein the individual elements (3) are formed protruding from the first joining surface (11) and extend along a respective axis (A),
c) materially joining the first (1) and second component (2) by producing a joining connection between the first (11) and second joining surface (21), wherein the marker structure (110) is arranged at least partially between the first (11) and second joining surface (12),
d) detecting at least one signal with a detection device (4), the signal being changed when damage occurs in the individual elements (3) of the at least two element types (111, 112),
e) evaluating the at least one signal from step d) to determine a damage state of the individual elements (3).

Description

The following invention relates to a method for determining the condition of a joint connection and to a hybrid component with a joint connection.

A variety of methods for determining the condition of a joint are known from the prior art. In this context, a joint is defined as a connection between at least two components, where the two components are joined together, for example, using a material-to-material joining process. The joining process used to join the components can be adhesive, such as bonding, so that components made of different materials, for example, can be bonded together.

Adhesive joining processes enable significant weight savings, as the use of fasteners such as rivets and/or screws can be dispensed with. Therefore, adhesive joining processes represent an essential technology for the production of hybrid components, structures, and materials, such as fiber-metal laminates.

Among the bonded joints, adhesive joints are particularly advantageous over welded or soldered joints, as they represent a relatively low-heat joining method that can be applied locally with virtually no heat input to the components. "Structural bonding," for example, can be used to create large-area joints, enabling force transmission across the entire bonded surface without impairing the component through drilled holes for screws or rivets, or weakening the joint structure.

In addition, hybrid composites and adhesive joints made of fiber-reinforced plastics and metallic materials can also be produced using adhesive joining processes.

In the field of thermosetting matrix systems, for example, vacuum, autoclave, resin transfer molding (RTM) and pressing processes are used to produce adhesive joints.

For thermoplastic matrix systems, compression molding or welding processes such as ultrasonic welding are primarily used to create a joint or to manufacture joined hybrid components. However, injection molding processes can also be used to join components.

Depending on the application and the materials to be joined, different joining methods are more or less suitable for creating a joint. However, all joining methods share the problem of determining the condition of the joint.

In the aforementioned joints, the detection of defects, for example due to incomplete or inadequate adhesion of the respective components, represents a particular challenge. Furthermore, such defects in an adhesively joined component can arise not only during the joining process during manufacturing, but also over the course of the service life of the joined component, for example due to external influences such as cyclic loads acting on the joint. Such defects or types of damage can include delamination, crack formation, or crack propagation. Due to the fact that the aforementioned types of damage cannot be detected or can only be detected inadequately after the component has been joined and/or during operation of a joined component, adhesive joining processes are often combined with other joining processes in practice in order to create joints that meet the requirements, particularly with regard to long-term operational reliability. The lack of knowledge about the current damage state of the joint thus leads to a kind of over-dimensioning of the joint.

In aviation, for example, glued joints are additionally reinforced with rivets, which results in a high additional weight and further manufacturing costs.

A disadvantage of joints, and particularly of adhesive joints from the state of the art, is the inability to detect damage and damage processes, particularly during component operation. Cyclic operating loads acting on the joint are particularly critical. While joints can be examined using an X-ray machine, for example, the size of the joint to be examined is limited to the size of the X-ray machine. Furthermore, such an examination cannot determine the condition of a joint in a component that is in operation and therefore subject to dynamic loads.

Currently, there are no or only inadequate methods available for detecting damage to an adhesive joint in a dynamic state. In practice, the adhesively joined components are examined for damage during maintenance, so This is the earliest possible point in time to detect a defective adhesive joint. Due to the currently inadequate detection options for joints, it is necessary to select inspection intervals so that no critical damage can occur in the area of the joint between inspection times. Such damage can, for example, be cracks outside or inside the joint, which, however, are only detectable once the damage has reached a certain dimension suitable for visual detection or detection, for example, using ultrasonic detection.

Based on the described disadvantages of the methods known from the prior art, the object of the present invention is to provide a method for determining the condition of a joint, and in particular of an adhesive joint. Furthermore, the object of the present invention is to provide a hybrid component with a joint, wherein the condition of the joint can be determined in a particularly simple manner.

According to a first aspect, the present invention relates to a method for determining the condition of a joint.

1. a) Bereitstellen eines ersten Bauteils mit einer ersten Fügeoberfläche und eines zweiten Bauteils mit einer zweiten Fügeoberfläche,
2. b) Ausbilden einer Markerstruktur mit mindestens zwei voneinander unterschiedlichen Elementarten, wobei jede der unterschiedlichen Elementarten eine Mehrzahl von Einzelelementen umfasst, welche jeweils zumindest über einen Flächenanteil der ersten Fügeoberfläche des ersten Bauteils ausgebildet werden und wobei die Einzelelemente von der ersten Fügeoberfläche vorstehend ausgebildet werden und sich entlang einer jeweiligen Verlaufsachse erstrecken,
3. c) stoffschlüssiges Fügen des ersten und zweiten Bauteils durch Herstellen einer Fügeverbindung zwischen der ersten und zweiten Fügeoberfläche, wobei die Markerstruktur zumindest anteilig zwischen der ersten und zweiten Fügeoberfläche angeordnet ist,
4. d) Erfassen mindestens eines Signals mit einer Detektionseinrichtung, wobei das Signal bei Auftreten einer Schädigung in den Einzelelementen der mindestens zwei Elementarten verändert wird,
5. e) Auswerten des mindestens einen Signals aus Schritt d) zur Bestimmung eines Schädigungszustandes der Einzelelemente.

The method according to the invention for determining the condition of a joint comprises the following steps:

1. a) providing a first component with a first joining surface and a second component with a second joining surface,
2. b) forming a marker structure with at least two different element types, wherein each of the different element types comprises a plurality of individual elements, which are each formed over at least a portion of the first joining surface of the first component, and wherein the individual elements are formed protruding from the first joining surface and extend along a respective axis,
3. c) joining the first and second components by producing a joint between the first and second joining surfaces, wherein the marker structure is arranged at least partially between the first and second joining surfaces,
4. d) detecting at least one signal with a detection device, the signal being changed when damage occurs in the individual elements of the at least two element types,
5. e) evaluating the at least one signal from step d) to determine a damage state of the individual elements.

• - einem ersten Bauteil mit einer ersten Fügeoberfläche,
• - einem zweiten Bauteil mit einer zweiten Fügeoberfläche und
• - einer Markerstruktur mit mindestens zwei voneinander unterschiedlichen Elementarten, wobei jede der unterschiedlichen Elementarten eine Mehrzahl von Einzelelementen umfasst, welche jeweils zumindest über einen Flächenanteil der ersten Fügeoberfläche des ersten Bauteils ausgebildet ist,

wobei sich die Einzelelemente von der ersten Fügeoberfläche abstehend entlang einer jeweiligen Verlaufsachse erstrecken,
wobei eine stoffschlüssige Fügeverbindung zwischen der ersten und zweiten Fügeoberfläche ausgebildet ist und wobei die Markerstruktur zumindest anteilig zwischen der ersten und zweiten Fügeoberfläche angeordnet ist.According to a second aspect, the present invention further relates to a hybrid component with a joint and

• - a first component with a first joining surface,
• - a second component with a second joining surface and
• - a marker structure with at least two different element types, each of the different element types comprising a plurality of individual elements, each of which is formed over at least a portion of the first joining surface of the first component,

wherein the individual elements extend from the first joining surface along a respective axis,
wherein a material-to-material joining connection is formed between the first and second joining surfaces and wherein the marker structure is arranged at least partially between the first and second joining surfaces.

The first component can have a wide variety of geometries, whereby the first joining surface can have varying contours and surfaces and is not limited to a flat surface according to the invention.

Furthermore, the first component is not limited in its dimensions, so that both microscopic and macroscopic component sizes can be used for the method according to the invention. Macroscopic components are preferably used in the aerospace and automotive industries, so the method according to the invention is particularly advantageously suited for components from these sectors. The first component can, for example, be designed either as a solid plate or as a comparatively thin sheet and can have both concave and convex structures. The same applies to the second component with a second joining surface.

According to the invention, a marker structure is formed on the first joining surface of the first component. The marker structure has at least two different element types, each of the element types comprising a plurality of individual elements. The individual elements are formed so as to protrude at least over a surface portion of the first joining surface of the first component and extend along a respective axis. Thus, with the inventive With the method according to the invention, it is particularly advantageous to use only a portion of the first joining surface and not the entire first joining surface, so that only the condition of a portion of the joining connection can be determined. The method according to the invention thus makes it possible to determine the condition of the joining connection in locally defined areas or portions of the total area. The individual elements can also be formed in several partial areas of the first joining surface.

In this context, an individual element can be, for example, a pin arranged on a surface portion of the first joining surface and protruding from this joining surface. The pin extends along its axis of extension, so that the pin is arranged, for example, orthogonally to the joining surface. The pin can be designed as a straight pin, but meandering or hook-shaped forms of the individual elements are also possible and encompassed by the method and the component according to the invention.

Because the individual elements extend along the axis of the joint, projecting from the first joining surface and thus being formed between the first and second joining surfaces, the marker structure forms an additional load-bearing element within the integral joint. According to the invention, the marker structure is preferably embedded in the material forming the joint.

At least two identical individual elements form one element type. At least two different element types, in turn, form the marker structure according to the invention. The marker structure thus has at least four protruding individual elements arranged on the first joining surface. The individual elements, designed as pins, for example, can differ in that they have different diameters, for example. In other words, the marker structure can have more massive and finer pins. The finer pins, for example, can already exhibit structural deformations such as permanent plastic deformation or even fracture under a specified first load, whereas the more massive pins can still withstand this defined first load and thus exhibit no permanent deformation.

When the same defined first load is applied to the more massive pins as to the finer pins, the more massive pins, due to their larger diameter, still behave elastically and thus differently than the finer pins, which, due to their smaller diameter, can already exhibit plastic deformation or fracture under the defined first load. Furthermore, acoustic signals, for example, can be emitted when a pin deforms due to the load.

According to method step c) and according to the component according to the invention, the first and second components are joined in a material-to-material bond by creating a joint between the first and second joining surfaces. The material-to-material bonding can be achieved, for example, by a thermal joining process or by an adhesive joining process, such as a bonding process. The marker structure is located within the joint and is arranged on the first joining surface of the first component and thus between the first and second components and thus, in turn, at least partially between the first and second component surfaces. The marker structure is thus located at least partially within the joint, whereby the material-to-material bonding can be adapted to the marker structure. If the marker structure consists of a material with a comparatively low melting temperature, a joining process can be selected in which comparatively low joining temperatures exist. Comparatively low temperatures exist, for example, in bonding processes.

The inventive method according to the first aspect of the invention provides for the detection of at least one signal with a detection device. Furthermore, the inventive component according to the second aspect of the invention provides that the marker structure is detectable by a detection device. The signal to be detected by the detection device changes upon the occurrence of damage or deformation of at least one individual element or initially occurs in conjunction with this, so that a change in state that has occurred in the joint can be inferred from the signal. The change in state of the individual element can be triggered by breakage or irreversible deformation.

The detection device, via which the signal is detected, can be designed as a detection system that can be attached, for example, by clamping, gluing, or screwing to the joined component or near the joint. The signal generated by the damage or deformation of the individual element is transmitted from the point of origin, the individual element, through the joint towards the detection device and then detected by it. However, the detection device can also be permanently arranged, in particular embedded, in the region of the joining connection in the region of the first and/or second joining surface.

Within the scope of the invention, the detection device can be a resistance measuring device, an X-ray device, a computer tomography scanner, a device that records structure-borne sound emissions, a thermographic sensor system, etc. The structure-borne sound emission can be an acoustic signal emitted by a damaged individual element, for example, due to a fracture of the individual element. The damage occurring in the marker structure, which can be detected by the detection device, can advantageously be used to draw conclusions about the condition of the marker structure and thus the condition of the joint. A particularly advantageous feature is that neither the joint nor the hybrid component need to be destroyed for the condition detection. The joint is thus examined in a completely non-destructive manner, which can save time and money during maintenance and inspection of a component. Furthermore, the method according to the invention and the hybrid component according to the invention can save resources because non-destructive testing provides insights into the condition of the joint, allowing early action to be taken to counteract overloading and/or wear of the component. Furthermore, the method according to the invention and the hybrid component according to the invention are suitable for so-called live monitoring, i.e., monitoring the component, or more precisely, the joint, while the component is in use.

Alternatively or in addition to an acoustic signal, the signal for damage detection can also be in the form of a resistance or a change in resistance, which can be detected with the detection device. If, for example, the resistance of the joined component changes due to the occurrence of deformation or damage to an individual element, the changed resistance can be used to determine the condition of the marker structure or the joint connection, or the condition of the joined component.

Furthermore, the detectable signal can be correlated with the time of the damage or deformation event, so that the signal can advantageously be used to infer the state and the temporal change in state of the joint. Of course, the detectable signal can occur not only at a single individual element, but also at multiple individual elements at different positions within the joint.

At least one signal is evaluated to determine the damage status of the individual elements. Based on the evaluation, the position and type of damage to the joint can be derived. The position of the state change is determined from the position at which the signal is generated, and a temporal change in the state of the joint is determined from several temporally offset signals.

By evaluating the damage signals from spatially resolved areas of the joint, it is possible to derive a prognosis for the component or joint in terms of its remaining service life or the need for maintenance. Thus, by determining the damage state of the individual elements or a single element, the damage state of the joint can be deduced, whereby the damage state of the joint can be determined with temporal and spatial resolution.

The method according to the invention also makes it possible to make a prediction regarding one or more future damage states of an individual element. An individual element can emit a signal without already being damaged. In this case, the signal can be an electrical resistance, for example. This signal can be emitted by a non-critical elastic or plastic deformation of an individual element and subsequently detected by the signaling device. If the elastic deformation subsequently reaches a critical value, the emitted signal also changes. Thus, even from an initially non-critical signal, conclusions can be drawn about a potentially future critical signal and a potentially future damage state of the individual element or the joint. The detection method according to the invention also makes it possible to detect locally resolved elastic deformations in the joint.

The method according to the invention allows the damage state of an individual element and thus the damage state of a joint to be determined in a particularly simple manner. The condition of the joint can be determined both during loading of a component and in the unloaded resting state, for example during maintenance. The method according to the invention thus offers the advantage of providing a monitoring method for joints. On the other hand, maintenance work at joints can be advantageously reduced, since these can be counteracted with information about the condition of the joint, for example by adapting the load to the joint or to the component. At the same time, the method according to the invention advantageously represents a non-destructive method. The maintenance method according to the invention can also be used to initiate proactive maintenance measures depending on deformations and/or damage that occur in the area of the joint.

Preferably, according to the first aspect of the invention, which relates to the method according to the invention, and according to the second aspect of the invention, which relates to the hybrid component according to the invention, the first component is provided as a metallic component. For example, the first component can be made of titanium or aluminum, although the metallic component can also consist of a metallic alloy such as steel, brass, or duralumin. By providing a metallic component, the method according to the invention and the component according to the invention can be used particularly advantageously for a variety of applications.

In a preferred embodiment according to the first and second aspects of the present invention, the second component is provided as a fiber composite component, preferably as a fiber composite plastic component. Fiber composite and fiber composite plastic components have a high degree of application depth in the economical processing of today's industry. Such a fiber composite component can, for example, consist of a glass fiber or carbon fiber composite with a thermoset or thermoplastic matrix. The choice of material depends on the technical requirements of the application, the cost flexibility, and any limitations in manufacturing options. By using the method according to the invention with a fiber composite component as the second component, this can be particularly advantageously combined with a joining method in which the first and second components are joined by pressing. Such methods are used, for example, in the automotive and aviation industries.

According to the first aspect of the invention, it is preferably provided that in step c) during the material-to-material joining of the first component to the second component, at least a portion of the marker structure penetrates into the second component in the region of the second joining surface and is embedded in the second component.

According to the second aspect of the invention, it is preferably provided that at least a portion of the marker structure penetrates into the second component in the region of the second joining surface.

The marker structure can be penetrated and embedded into the second component by external pressure applied by a machine, resulting in a particularly strong joint. For example, a first metallic component can be joined to a second component made of fiber-reinforced plastic using a hot-pressing process, with a portion of the marker structure applied to the metallic component penetrating the fiber-reinforced plastic component during the hot-pressing process. The resulting hybrid joint exhibits particularly strong strength.

Preferably, according to the first aspect of the invention, it is provided that in step d) the detection of the at least one signal is carried out with the detection device, wherein the signal is changed when damage to a part of the fiber-reinforced plastic component occurs.

By embedding the marker structure, the signal to be detected can be additionally or alternatively modified, for example, by a damaged fiber of a fiber-reinforced plastic component. The signal can also be modified without damage to an individual element of the marker structure occurring, whereby the evaluation of the at least one signal carried out according to method step e) can be carried out in such a way that, for example, the damage state of a damaged fiber of the fiber-reinforced plastic surrounding the individual element is determined. Thus, the condition of the joint can be deduced from a damaged fiber alone. The method according to the invention can thus advantageously determine the condition of the joint even with comparatively minor damage.

Furthermore, the embedding of the marker structure makes it more difficult for the marker structure to shift relative to the second component in at least one spatial direction, so that the joint advantageously has additional stability.

Preferably, according to the first aspect of the present invention, the individual elements are designed such that they have at least one of the features selected from the following group.

• 1) Die Einzelelemente weisen orthogonal zu der Verlaufsachse eine definierte Querschnittsform auf;
• 2) Die Einzelelemente weisen in einer Ebene orthogonal zu der Verlaufsachse entlang der Verlaufsachse eine variierende Abmessung und /oder Querschnittsform auf;
• 3) Die Einzelelemente weisen eine Verlaufsachse auf, welche einen definierten Winkel im Bereich von 30° bis 90° zwischen der Verlaufsachse und der ersten Fügeoberfläche bzw. relativ zu einer Tangente in dem Schnittpunkt des Einzelelementes mit der ersten Fügeoberfläche einschließt;
• 4) Die Einzelelemente sind entlang der ersten Fügeoberfläche in ungleichen Abständen zueinander angeordnet;
• 5) Die Einzelelemente bestehen aus einem definierten metallischen Werkstoff und/oder einer definierten metallischen Legierung;
• 6) Die unterschiedlichen Einzelelemente weisen orthogonal zu der Verlaufsachse unterschiedliche Abmessungen und/oder Querschnittsformen auf.

According to the second aspect of the present invention, the individual elements preferably have at least one of the criteria of the following group:

• 1) The individual elements have a defined cross-sectional shape orthogonal to the axis of travel;
• 2) The individual elements have a varying dimension and/or cross-sectional shape in a plane orthogonal to the axis of travel along the axis of travel;
• 3) The individual elements have a course axis which encloses a defined angle in the range of 30° to 90° between the course axis and the first joining surface or relative to a tangent at the intersection point of the individual element with the first joining surface;
• 4) The individual elements are arranged at unequal distances from each other along the first joining surface;
• 5) The individual elements consist of a defined metallic material and/or a defined metallic alloy;
• 6) The different individual elements have different dimensions and/or cross-sectional shapes orthogonal to the axis.

According to the invention, the individual elements can thus have a variety of different geometric shapes. An individual element that has a defined cross-sectional shape orthogonal to the axis of travel can, for example, be designed as a pin, a column, or as a rod-like feature.

An individual element that has a varying dimension along the axis of travel can be a pin that has a larger diameter in a central region than in the region that is close to the joining surface and facing away from the region of the joining surface. In other words: in one exemplary embodiment, the pin can have a bulbous characteristic. Likewise, the design of the individual element as a pin with multiple prongs is possible, wherein the prongs of the pin can be formed approximately parallel to the joining surface. In this embodiment, the prongs of the pin function as resistance elements arranged on the pin. With such a design of the individual element, it can only be released from the joining connection with increased force. This means that the individual element cannot be easily pulled out of the joining connection due to delamination or debonding to the material of the joining connection due to a lack of bond.

If the axis of travel and the first joining surface form an angle in the range of 30°-90°, the individual elements can also be arranged at an angle on the joining surface. Not all individual elements need to have the same defined angle, so that individual elements can be arranged at different inclinations on the first joining surface. The individual elements arranged at an angle can be particularly advantageously aligned in the direction of an expected load or explicitly against an expected load. A signal emitted by an individual element inclined in this way can be particularly advantageously detected by the detection device. By means of individual elements that are explicitly aligned to an application in this way, the change in state of the joint can be determined particularly precisely.

If the individual elements are arranged at unequal distances from one another along the first joining surface, individual elements can be arranged at a higher density at a location with increased loading than at a location with lower loading. By arranging the individual elements at unequal distances, the method according to the invention can be adapted accordingly to a component geometry and/or an expected load case. Depending on the geometry of the component, for example, more individual elements can be arranged at locations with higher local loading, and fewer individual elements can be arranged at locations with lower loading, so that the individual elements are arranged at unequal distances from one another along the first joining surface.

Furthermore, the individual elements can consist of a defined metallic material and/or a defined metallic alloy and/or a ceramic material and/or a plastic and/or a composite material. Of course, not only the individual elements, but also the element types can be made of different material classes. By configuring the individual elements in this way, the method according to the invention can be advantageously adapted to different static and dynamic loading cases and to the respective application of the joint.

If the different individual elements orthogonal to the axis have different dimensions and/or cross-sectional shapes, the individual elements can be adapted to the component geometry and the locally varying loads of the joint. Furthermore, the different individual elements emit different signals, so that the method according to the invention can be tailored specifically to the application.

Preferably, according to the first aspect of the present invention, it is provided that in step b) the individual elements are connected to form a grid and/or a loop and/or the individual elements are formed in the form of a column and/or a pin and/or a pin with a hemisphere and/or a sphere and/or with at least one barb and/or an anchoring element projecting laterally to the axis of travel.

According to the second aspect of the present invention, it is provided that the hybrid component preferably comprises individual elements, wherein the individual elements are connected to form a grid and/or a loop and/or have the shape of a column and/or a pin and/or a pin with a hemisphere and/or sphere and/or with at least one barb and/or an anchoring element projecting laterally to the axis of extension.

If the individual elements are connected to form a grid and/or a loop, at least two individual elements can already form a grid and/or a loop. However, more than two individual elements or all individual elements of one element type can be connected to form a grid or a loop with many loop elements. By connecting several individual elements to form a grid and/or loop, a larger area of the first joining surface is covered with connected individual elements, so that the condition of the joint can advantageously be deduced from the grid and/or the loop. The method according to the invention can then determine the condition with respect to an area covered by the grid or loop, rather than with respect to a single point. The method according to the invention, in which the individual elements are connected to form a grid or loop, can thus advantageously be used for large components.

The individual element designed as a column has a shape in which the length of the column extending in the direction of travel is longer than a width of the column, which corresponds to a diameter of the column. The column can have an elliptical cross-section and can have an approximately flat top surface. However, the individual element can also consist of column elements, with the diameter of the column being greater than the length of the column.

The individual element designed as a pin basically has a similar shape to a column, but has a comparatively much narrower cross-section and can have a pointed top surface. Due to the narrower cross-section of the pin compared to the column, it is plastically deformed under lower load influences than the column. Both the column and the pin can have a pointed top surface, with the tip preferably running through the axis of the pin and column. The column and pin have a shell surface that has no further structural features, so that both the column and the pin can penetrate the second component, which consists of a fiber composite component, with comparatively little resistance.

If the pin and/or the column have a hemisphere, this can be formed on the top surface or in an upper region of the pin. The flat base of the hemisphere can be arranged parallel to the first joining surface of the first component. In other words, the hemisphere can be arranged on the pin. Furthermore, the hemisphere can be arranged in a central region or in an upper region or at the end of the pin facing away from the joining surface. Due to the hemisphere arranged on the pin, the pin has a type of anchoring element so that the pin with the hemisphere can only be released again with increased force after penetrating the second component during the joining process, compared to a single element without a hemisphere. The joining connection that has an individual element designed in this way has the additional advantage that the strength and damage tolerance of the joining connection can be further increased. In addition, it is ensured that the occurrence of damage in the joint also leads to damage in the formed individual elements.

Another design provides for the pin to have a ball, with the center of the ball running through the pin's axis. Naturally, the resistance that must be overcome to release the joint is significantly influenced by the size of the ball.

In order to increase the resistance to releasing the individual elements, at least one barb can be formed on the pin. The barb can be The end of the individual element should be tapered towards the first joining surface so that the barb provides particularly strong resistance to the loosening of the individual element.

It can also be provided that an anchoring element protruding laterally from the axis of travel is formed on the individual element. This anchoring element can be designed, for example, as a barb or a combination of several barbs or a series of barbs. Furthermore, the anchoring element can also have a significantly more complex structure than a barb.

The different configurations of the individual elements can advantageously influence the stability of the connection between the individual elements and the material of the joint. Furthermore, the design of the individual element can influence the signal generated when damage occurs to the individual element. For example, the signal from a damaged pin differs significantly from the signal from a damaged grid. This advantageously allows conclusions to be drawn about the type of damaged individual element from the signal. Of course, different types of individual elements can also be combined in a joint. The different configurations of the individual elements thus allow the method according to the invention to be designed in a particularly flexible manner.

In a preferred embodiment of the first aspect of the invention, it is provided that in step b) the formation of the marker structure takes place at least partially by an additive manufacturing process on the first joining surface. The marker structure, in particular the individual elements, can be produced, for example, by means of 3D printing, investment casting, electron beam melting, a machining process, or an additive or subtractive laser process. The marker structure can thus be produced on the first joining surface using different processes, adapted to the material of the first component. Due to the marker structure optionally formed at least partially by an additive manufacturing process, the method according to the invention can particularly advantageously use a variety of materials and utilize marker structures with undercuts and penetrations such as internal channels.

According to the first aspect of the present invention, it is preferably provided that in step c) the first component and the second component are joined in a material-to-material bond using a thermal joining process and/or an adhesive joining process. The adhesive process offers the advantage that almost all material classes can be joined together in any combination in a long-term, durable manner. The adhesive joining process can, for example, be an adhesive bonding process. Furthermore, the material properties of the first component and the second component are almost completely retained, since no thermal energy, or only very low or short-term thermal energy, which influences the structure of the materials to be joined, is introduced into the components during the adhesive joining process. Furthermore, it is possible to integrate properties into the joint connection using an adhesive joining process that go beyond the actual connection of the first and second components. For example, an adhesive joining connection can also provide insulation, sealing against gases and liquids, vibration damping, corrosion protection, or compensation for different joining part dynamics. Furthermore, the adhesive joining process can be adapted to the marker structure.

Alternatively or additionally, the first and second components can be joined using a thermal joining process. A distinction must be made between local and global thermal joining processes. In a global joining process, the entire component group, consisting of at least the first and second components, is heated. In the local thermal joining process, thermal energy is introduced at the interface between the first and second components. Thermal joining processes used within the scope of the invention can be, for example, ultrasonic welding, arc welding, beam welding, electron beam welding, soldering or stress-relieving annealing, whereby the thermal joining process can be adapted to the marker structure. Using a thermal joining process, the first and second components are advantageously joined to one another in a particularly stable manner.

In a preferred embodiment of the first aspect of the invention, it is provided that in step d), the detection device detects at least one electrical and/or electromagnetic and/or acoustic signal. The electrical signal can, for example, be an electrical resistance, which is detected via a detection device designed as a resistance measuring device. The electrical resistance of the joint with undamaged individual elements or an undamaged structure differs from the resistance of the same joint with a damaged marker structure or with damaged individual elements. The condition of the joint can thus be determined from the different resistance.

Additionally or alternatively, the detection device can detect an electromagnetic signal. An electromagnetic signal can, for example, be a signal based on X-ray radiation. The X-ray radiation is first emitted by an X-ray device, then transmitted through the joint, and then detected by another part of the detection device designed as an X-ray device. The detected signal of an undamaged individual element differs from the detected signal of a damaged individual element. By detecting an electromagnetic signal designed as an X-ray signal, the condition of a joint can advantageously be determined optically. Of course, other electromagnetic waves can also be used in this context instead of X-ray radiation.

Additionally or alternatively, the detection device can detect at least one acoustic signal. The acoustic signal can be caused by the damage process of the individual element. For example, an individual element emits an acoustic signal when it is elastically and/or plastically deformed or suffers a complete fracture or failure. The acoustic signal can be used to draw both qualitative and quantitative conclusions about the condition of the joint. For example, the acoustic signal of an individual element designed as a pin differs from the acoustic signal of an individual element designed as a column if the pin and the column break. The detection device, which detects an acoustic signal, can be arranged by clamping or screwing on the joint or on the joined component. Particularly advantageously, the detection device can be permanently incorporated in the area of the joint, for example by being embedded in the joint. In addition to the location of the damage, the acoustic signal can also be used to determine the type of damage to the individual element, for example, whether the individual element is fractured or deformed. The type of damage can be used to assess the condition of the component or joint, which in turn can be used to determine the remaining service life and/or the need for repair of the component or joint before critical and/or spontaneous failure. The condition of the joint can be advantageously determined during loading or in the unloaded state.

In a preferred embodiment according to the first aspect of the invention, in step d), the detection device is arranged at a defined distance from the joint connection. The defined distance can, for example, be virtually zero if the detection device is clamped or screwed or arranged in some other way on the joint connection or on the first and second components. However, the detection device can also be arranged on the joint connection at a distance that is not equal to zero, for example, if the detection device is designed as an X-ray device. In this case, the distance between the detection device and the joint connection can advantageously be adapted to the geometry of the joint connection or to the geometry of the joined components. It can also be provided that the distance between the joint connection and the detection device is adapted to the signal to be evaluated, so that the detection device is arranged, for example, step by step at different positions on the joint connection. The detection device detects at least one signal at each step and determines the condition of the joint step by step. Due to the defined distance, the method according to the invention can determine the condition of the joint particularly advantageously, and at the same time, the method can be used flexibly for components and joints with different geometries.

In a preferred embodiment, according to the first aspect of the invention, steps d) and e) are performed multiple times. The multiple execution can take place at a time interval that can be, for example, one second or several hours, in particular several hundred operating hours of the joined components, such as flight hours. The multiple execution of steps d) and e), in which the time interval between the steps is several operating hours, such as flight hours, can be carried out in particular for a joint arranged in a component of an aircraft or spacecraft. Since maintenance or inspection is regularly scheduled for such joints after a predetermined number of flight hours, the method according to the invention is particularly suitable for applications in aerospace. By performing steps d) and e) multiple times, the method according to the invention determines the condition of the joint particularly advantageously over a time course, so that the condition of the joint can be advantageously evaluated.

Preferably, according to the first aspect of the invention, at least one load is applied to the joint after step c). The applied load can be static or dynamic, wherein For example, tensile compressive stress on the joint can be regarded as a static load, and tensile compressive stress on the joint that changes over time can be regarded as a dynamic load. The corresponding signal detected by the detection device differs depending on the type of load. The method according to the invention can therefore advantageously determine the condition of a joint that is subjected to static and/or dynamic loads. So-called life monitoring or structural health monitoring is particularly advantageous in this context, as the signal can be evaluated almost simultaneously with the occurrence of the load or subsequently within a short interval. For example, the signals from the joint can be recorded during an aircraft flight, and after the flight, the signals can be evaluated before the next flight in order to determine the condition of the joint. This means that conclusions about the condition of the joint can be drawn almost immediately from a static and/or dynamic load on the joint.

In a particularly preferred embodiment, according to the first aspect of the invention, at least the first and/or second joining surface is chemically and/or mechanically and/or physically pretreated prior to step c). Chemical pretreatment can be etching or pickling. Mechanical pretreatment can be polishing or grinding on the first and/or second joining surface. Physical pretreatment can be carried out by plasma treatment or a laser-based cleaning process, so-called laser cleaning. Depending on the material and the surface quality of the component, mechanical and/or chemical and/or physical pretreatment is preferable for the respective component. The pretreatment removes unwanted surface films and impurities and/or changes the surface activity and/or creates a desired surface structure. Thus, the chemical and/or mechanical and/or physical pretreatment cleans the first and/or second joining surface, so that the first and second components can be joined particularly advantageously.

In a preferred embodiment according to the second aspect of the invention, it is provided that a first of the at least two element types is designed to fail mechanically under a first load value, wherein a second of the at least two element types is designed to fail mechanically under a second load value, wherein the first load value is smaller than the second load value. In this case, the first element type can, for example, be made of a different material than the second element type. Alternatively, the first and second element types can have the same geometric shape but be dimensioned differently. In other words: the first element type can be designed as a thick pin and the second element type can be designed as a thin pin, so that the thin pin fails at the first load value and the thick pin only fails at the second load value, which is greater than the first load value. Of course, the first element type of the at least two element types can also be designed from a first material and with a first shape, and the second element type can be designed from a second material with a second shape. By configuring the at least two element types in this way, the joint can be advantageously adapted to the geometry of the hybrid component and, furthermore, the joint can be adapted to the loads acting on the component. The hybrid component with the joint can thus be advantageously used for a wide variety of applications.

According to the second aspect of the invention, the marker structure is preferably arranged at least partially at locations with increased mechanical stress on the hybrid component. Increased mechanical stress occurs, for example, in the edge regions of the joint. The marker structure can have a different configuration at locations with increased mechanical stress than at locations without increased mechanical stress. The joint can thus be advantageously used on a hybrid component that is exposed to particularly high mechanical stress.

In the following, preferred embodiments of the method according to the invention and of the hybrid component according to the invention are explained in more detail with reference to the following figures.

• 1 schematische Darstellungen ausgewählter Verfahrensschritte einer beispielhaften Ausführungsform des erfindungsgemäßen Verfahrens zur Zustandsbestimmung einer Fügeverbindung,
• 2 eine schematische Darstellung einer beispielhaften Ausführungsform eines erfindungsgemäßen hybriden Bauteils mit einer Fügeverbindung, und
• 3 schematische Darstellungen verschiedener beispielhafter Ausführungsformen von Einzelelementen der Markerstruktur.

They show:

• 1 schematic representations of selected method steps of an exemplary embodiment of the method according to the invention for determining the condition of a joint,
• 2 a schematic representation of an exemplary embodiment of a hybrid component according to the invention with a joint connection, and
• 3 schematic representations of various exemplary embodiments of individual elements of the marker structure.

The 1a to 1d show schematic representations of selected method steps according to an exemplary embodiment of the method according to the invention for determining the condition of a joint.

1a shows the provided first component 1 with a first joining surface 11, wherein the marker structure 110 is formed on the first joining surface 11. The marker structure 110 has different element types 111, 112. Each of the different element types 111, 112 comprises a plurality of individual elements 3, wherein the individual elements 31 shown have the shape of a column. As shown, the column-like individual elements 31 of the first element type 111 have a different diameter than the column-like individual elements 31 of the second element type 112. Of course, other geometric characteristics such as the length or the alignment of the column-like individual elements 31 relative to one another can also vary.

According to the illustrated embodiment, the individual elements 3 of an element type 111, 112 are arranged uniformly relative to one another. Of course, the arrangement can also be adapted to the respective application, so that the distances between the respective individual elements 3 can vary. For example, in an area in which the signal is to be detected with particularly precise location, the individual elements 3 can be arranged particularly densely, i.e., with a relatively small spatial distance from one another. For example, in surface areas where high local loading is to be expected, more individual elements per unit area can be provided with a smaller distance relative to one another than in surface areas where lower loads are to be expected.

The individual elements of the marker structure 110 can be arranged on the first joining surface 11, for example, by an additive manufacturing process. In the region of the first joining surface 11, an adhesion-promoting layer can also be provided for applying the marker structure, at least in partial regions of the first joining surface 11.

1b shows, by way of example, method step c), according to which the first component 1 and the second component 2 are connected to one another by producing a joining connection between the first joining surface 11 and the second joining surface 21. In the exemplary embodiment shown, the columnar individual elements 31 of the marker structure 110 penetrate at least partially into the second joining surface 21, wherein the first and second components 1, 2 are moved towards one another in the Y direction. The material-to-material joining can be carried out, for example, by an adhesive process, wherein an adhesive is introduced in the region of the first and second joining surfaces 11, 12 and in the region of the marker structure 110. The first and second components 1, 2 can thus be materially connected by the adhesive process.

In an exemplary embodiment, the second component 2 with the second joining surface 21 can consist, for example, of a fiber-reinforced plastic component, wherein in method step c) the matrix material has not yet been cured, so that the individual elements 31 of the marker structure 110 can penetrate between individual fibers of the fiber-reinforced plastic component when the first and second components 1, 2 are joined together and, in addition to the adhesive connection, are at least partially also positively connected to one another by the individual elements 31 penetrating the second joining surface 21. The additional partial positive connection is created in that the individual elements 31, which are arranged between the individual fibers, prevent vertical displacement of the first and second components 1, 2 relative to one another in the X direction. The joint connection produced by the method according to the invention thus has the further advantage of particularly high stability.

1c shows the joint connection produced by the method according to the invention or a hybrid component 10, wherein the individual elements 31 of the marker structure 110 have almost completely penetrated into the material of the second component 2 in the region of the second joining surface 21. A detection device 4 is arranged on the first component 1, which, for example, detects an acoustic signal from the joint connection or from the hybrid component 10. The detection device 4 can be designed, for example, in the form of a device that detects structure-borne sound emissions.

The recorded signal can be evaluated and graphically displayed by an evaluation device 5 connected to the detection device 4. The temporal course of the acoustic signal, which according to 1c recorded with the detection device 4, does not show any significant deflections, since no significant damage occurred on the individual elements 31 during the signal recording period. The course of the signal according to 1c shows an example of a so-called "background noise" of the signal. The detection device 4 offers the advantage that it can be particularly easily mounted on the first component 1, preferably in the area of the first joining surface. 11, without the hybrid component 10 having to be structurally modified.

1d shows the hybrid component 10 according to the invention, wherein an individual element 3a has been damaged by a load acting on the joint. The damage to the individual element 3a results in a signal that is detected by the detection device 4 and evaluated by the evaluation device 5. The detected signal can be an acoustic signal, for example a fracture noise, triggered by the damage. The signal detected by the detection device 4 can be graphically displayed by the evaluation device 5, so that the damage process, such as a fracture noise of the damaged individual element 3a, can be recognized as a signal peak in the illustrated schematic signal curve.

The method according to the invention thus makes it possible to draw conclusions about the state of the joint connection or the state of the hybrid component 10 according to the invention from a signal in a particularly simple manner. Destroying the joint connection or the hybrid component 10 is not necessary, so that the method according to the invention is particularly advantageously suited for live monitoring, but also for monitoring the hybrid component 10 or the joint connection while the hybrid component 10 is in use.

The 2 schematically shows a hybrid component 10 according to the invention, in which the second component 2 with the second joining surface 21 consists of a fiber composite material. The fiber composite component accordingly has various oriented fibers 6, 7, each arranged in layers in the second component 2. The layers with fibers 6 oriented in a first direction of the fiber composite component are arranged offset by 90° from the layers with fibers 7 oriented in a second direction. Such a layered arrangement of fibers is common in fiber composite components.

Particularly advantageous is the embedding of the marker structure 110 in the second component 2 in the region of the second joining surface 12, with individual elements 3 having proven particularly suitable which are designed as a pin with a hemisphere 33. In particular, if the second joining surface 21 or the second component 2 consists of a fiber composite plastic and the first component 1 and the second component 2 are joined by means of an adhesive process, the matrix material solidifies during the joining process on the individual element in the form of a pin with a hemisphere 33 in such a way that, in addition to the material-locking connection, a type of positive connection is also created between the first component 1 and the second component 2 after the matrix material has hardened. The cured matrix material engages behind the hemisphere and solidifies particularly advantageously between the flat plane of the hemisphere and the first joining surface 11. A joint produced in this way therefore has particularly high stability. Of course, according to the invention, the second component 2 can also be made from a material other than a fiber composite material, with an adhesive layer then being applied in the area of the second joining surface 21, for example, into which the individual elements 3 of the marker structure 110 can penetrate.

An essential feature of the method according to the invention and of the hybrid component according to the invention is the marker structure 110, which has at least two different element types 111, 112, each of the different element types comprising a plurality of individual elements 3. The 3a to 3f show different exemplary designs of the individual elements 3 of the marker structure 110. Depending on the load case and the respective component geometry, different designs of the individual elements 3 are suitable.

3a shows the first component 1 with the first joining surface 11, wherein individual elements 31 are arranged on the first joining surface 11, each having the shape of a column with a cross-sectional shape defined orthogonally to the axis A. The individual elements 31 formed as a column also have a flat end face that is arranged approximately parallel to the first joining surface 11.

3b shows individual elements 31 in the form of a column, wherein the individual element 31 has a running axis A which encloses a defined angle α in the range of 30° to 90° between the running axis A and the first joining surface 11. The individual elements 31 designed as a column in turn have a flat end face which, as shown in the example, is arranged approximately parallel to the first joining surface 11. Such a configuration of one of the individual elements 3 is suitable, for example, for a joint that is loaded relatively heavily and preferably from one direction. For example, the individual elements 31 inclined by the angle α can then be inclined in the direction from which the joint is particularly loaded.

3c shows the arrangement of individual elements 32, which have a pointed end opposite the first joining surface 11. Such Individual elements 32 designed as a pin are particularly suitable, for example, for penetrating a second component 2 in the region of a second joining surface 21, which consists, for example, of a fiber-reinforced plastic. The individual element 32 can be pressed between individual fibers of a fiber-reinforced plastic component via the tip of the pin, applying relatively little force. In the exemplary embodiment shown, the individual element 32 designed as a pin thus differs from the individual element 31 designed as a column by a tapered end region.

3D shows the design of an individual element 34, which has a different cross-sectional shape orthogonal to the axis A. The 3D The individual element 34 shown has a pin-shaped base body which has a spherical section in a central region. Such an individual element 34 can be inserted particularly easily into a second component surface 21 of a second component 2, which consists for example of a fiber composite plastic, due to the pointed end and, after the joining process, simultaneously represents increased resistance to separation of the joint due to the spherical shape in the central region of the individual element 34. Thus, during the joining process, an increased amount of force must initially be applied, for example in comparison to the joining process with an individual element 32 according to the 3c to the individual elements 34 according to the 3D in the second joining surface 21. However, to release such a joint, an increased amount of force is required, so that a joint which comprises the individual elements 34 according to the 3D has a particularly high level of stability.

According to the 3e The individual element 33 has a pin with a hemisphere. Such an individual element 33 has proven to be particularly advantageous for the material-to-material joining, for example by an adhesive process, of a first component 1 and a second component 2, wherein the second component 2 consists of a fiber-reinforced plastic. Via the tip and the rounded edge of the hemisphere, the individual element 33 can initially be introduced relatively easily into the adhesive layer during a material-to-material joining process, wherein the adhesive, after curing, is particularly advantageously arranged in an area between the first joining surface 11 and the flat surface of the hemisphere of the individual element 33. Thus, in addition to the material-to-material joining connection, an approximately positive-fitting joining connection is also created. Such a connection has proven to be particularly stable.

3f shows an individual element 35 that has at least one barb. Such an individual element with a barb 35 can particularly advantageously hook into a second joining surface 21 consisting of a fiber composite plastic, so that a particularly stable positive-locking joint is additionally created. Of course, the barbs of the individual elements 35 can also be formed in different directions, wherein the extension axis A of the respective individual elements 35 can also enclose an angle between the first joining surface 11 and the extension axis A that deviates from 90°. The individual element 35 formed with a barb can thus penetrate into the second joining surface 21 of the second component in a similar way to a hook-and-loop fastener principle, so that such a joint is particularly stable due to the additional positive joining.

3g shows the arrangement of individual elements 3, which are connected on the first joining surface 11 to form a grid 8. The grid 8 can, as shown, have two horizontally arranged strut-like structures. In the case of a damaged individual element 3 of a grid 8 according to 3g the signal emitted by the grid 8 differs significantly from the signal emitted by an individual element that is not arranged in a grid 8. Thus, the type of damaged individual element 3 can be advantageously deduced from the signal.

Of course, the method according to the invention or the hybrid component 10 according to the invention can also have a marker structure 110 in which, in addition to the individual elements 3 connected to form a grid 8, other types of individual elements 3 also occur. By connecting several individual elements 3 to form a grid 8, a comparatively larger area of the first joining surface 11 is covered with connected individual elements 3, so that the state of the joining connection can advantageously be deduced from the grid 8. The method according to the invention can thus be used particularly advantageously for large components.

3 hours shows an arrangement in which two individual elements 3 are connected to form a loop 9. The individual elements 3 connected to form a loop 9 cover a larger area of the first joining surface 11 of the first component 1, wherein the covered area is larger than the area covered by a single individual element 3 and smaller than the area covered by a grid 8 according to the 3g By connecting the individual elements 3 to form a loop 9, the state of a joint connection can thus be advantageously determined with respect to a spatial area can be determined. Of course, several individual elements can also be connected to form a loop 9. The method according to the invention or the hybrid component 10 according to the invention, in which the individual elements 3 are connected to form a loop 9, is thus advantageously also suitable for large components.

List of reference symbols

1

First component

11

First joining surface

110

Marker structure

111

first element type

112

second element type

2

Second component

21

Second joining surface

3

Single element

3a

Damaged individual element

31

Single element in the form of a column

32

Single element in the form of a pen with a tip

33

Single element in the form of a pen with tip and hemisphere

34

Single element in the form of a pen with tip and ball

35

Single element with at least one barb

4

Detection device

5

Evaluation device

6.7

Fibers of a fiber composite component

8

Grid

9

loop

A

gradient axis

Claims (23)

A method for determining the condition of a joint, comprising the following steps: a) providing a first component (1) with a first joining surface (11) and a second component (2) with a second joining surface (21), b) forming a marker structure (110) with at least two different element types (111, 112), wherein each of the different element types (111, 112) comprises a plurality of individual elements (3), each of which is formed over at least a portion of the surface of the first joining surface (11) of the first component (1), and wherein the individual elements (3) are formed protruding from the first joining surface (11) and extend along a respective axis (A), c) joining the first (1) and second components (2) by producing a joint between the first (11) and second joining surfaces (21), wherein the marker structure (110) is at least partially formed between the first (11) and second joining surface (12), d) detecting at least one signal with a detection device (4), wherein the signal is modified upon the occurrence of damage in the individual elements (3) of the at least two element types (111, 112), e) evaluating the at least one signal from step d) to determine a damage state of the individual elements (3). Procedure according to Claim 1 , wherein the first component (1) is provided as a metallic component. Procedure according to Claim 1 or 2 , wherein the second component (2) is provided as a fiber composite component, preferably as a fiber composite plastic component. Method according to one of the preceding claims, wherein in step c) during the material-to-material joining of the first component (1) to the second component (2), at least a portion of the marker structure (110) penetrates into the second component (2) in the region of the second joining surface (21) and is embedded in the second component (2). Procedure according to the Claims 3 and 4 , wherein in step d) the detection of the at least one signal is carried out with the detection device (4), wherein the signal is changed when damage to a part of the fiber-reinforced plastic component occurs. Method according to one of the preceding claims, wherein the individual elements (3) are designed such that they have at least one of the features selected from the following group: 1) The individual elements (3) have a defined cross-sectional shape orthogonal to the profile axis (A); 2) The individual elements (3) have a varying dimension in a plane orthogonal to the profile axis (A) along the profile axis (A); 3) The individual elements (3) have a profile axis (A) which encloses a defined angle (α) in the range from 30° to 90° between the profile axis (A) and the first joining surface (11); 4) The individual elements (3) are arranged at unequal distances from one another along the first joining surface (11); 5) The individual elements (3) consist of a defined metallic material and/or a defined metallic alloy and/or a ceramic material and/or a plastic and/or a composite material; 6) The different individual elements (3) have different dimensions and/or cross-sectional shapes orthogonal to the axis (A). Method according to one of the preceding claims, wherein in step b) the individual elements (3) are connected to form a grid (8) and/or a loop (9) and/or the individual elements (3) are designed in the form of a column (31) and/or a pin (32) and/or a pin with a hemisphere (33) and/or ball (34) and/or with at least one barb (35) and/or an anchoring element projecting laterally to the axis of travel (A). Method according to one of the preceding claims, wherein in step b) the formation of the marker structure (110) is carried out at least partially by an additive manufacturing process on the first joining surface (11). Method according to one of the preceding claims, wherein in step c) the first component (1) and the second component (2) are joined in a material-to-material manner using a thermal joining method and/or an adhesive joining method. Method according to one of the preceding claims, wherein in step d) the detection device (4) detects at least one electrical and/or electromagnetic and/or acoustic signal. Method according to one of the preceding claims, wherein in step d) the detection device (4) is arranged at a defined distance from the joint connection. Method according to one of the preceding claims, wherein steps d) and e) are carried out several times. Method according to one of the preceding claims, wherein after step c) at least one load is applied to the joint. Method according to one of the preceding claims, wherein before step c) at least the first (11) and/or second joining surface (21) is chemically and/or mechanically and/or physically pretreated. A hybrid component (10) with a joining connection and - a first component (1) with a first joining surface (11), - a second component (2) with a second joining surface (21), and - a marker structure (110) with at least two different element types (111, 112), wherein each of the different element types (111, 112) comprises a plurality of individual elements (3), each of which is formed over at least a portion of the surface of the first joining surface (11) of the first component (1), wherein the individual elements (3) extend protruding from the first joining surface (11) along a respective axis (A), wherein the integral joining connection is formed between the first (11) and second joining surfaces (21), and wherein the marker structure (110) is arranged at least partially between the first (11) and second joining surfaces (12). Hybrid component (10) according to Claim 15 , wherein the marker structure (110) is detectable by a detection device (4). Hybrid component (10) according to one of the preceding claims, wherein the first component (1) is a metallic component. Hybrid component (10) according to one of the preceding claims, wherein the second component (2) is a fiber composite component, preferably a fiber composite plastic component. Hybrid component (10) according to Claim 18 , wherein at least a portion of the marker structure (110) is embedded in the second component (2) in the region of the second joining surface (21). Hybrid component (10) according to one of the preceding claims, wherein a first of the at least two element types (111, 112) is designed to fail mechanically under a first load value, wherein a second of the at least two element types is designed to fail mechanically under a second load value, wherein the first load value is smaller than the second load value. Hybrid component (10) according to one of the preceding claims, wherein the marker structure (110) is arranged at least partially at locations with increased mechanical stress on the hybrid component. Hybrid component (10) according to one of the preceding claims, wherein the individual elements (3) have at least one of the criteria from the following group: 1) The individual elements (3) have a defined cross-sectional shape orthogonal to the axis (A); 2) The individual elements (3) have a defined cross-sectional shape orthogonal to the run axis (A) has a varying dimension; 3) The individual elements (3) have a run axis (A) which encloses a defined angle (α) in the range from 30° to 90° between the run axis (A) and the first joining surface; 4) The individual elements (3) are arranged at unequal distances from one another along the first joining surface (11); 5) The individual elements (3) consist of a defined metallic material and/or a defined metallic alloy and/or a ceramic material and/or a plastic and/or a composite material; 6) The different individual elements (3) have different dimensions and/or cross-sectional shapes orthogonal to the run axis (A). Hybrid component (10) according to one of the preceding claims, wherein the individual elements (3) are connected to form a grid (8) and/or a loop (9) and/or have the shape of a column (31) and/or a pin (32) and/or a pin with a hemisphere (33) and/or ball (34) and/or with at least one barb (35) and/or an anchoring element projecting laterally to the axis of travel (A).

Images