DE102020204360A1 - Method for producing a composite component, an assembly comprising the composite component and a motor vehicle - Google Patents

Abstract

The invention relates to a method for producing a composite component (10), in which a plate (1) made of a metallic material is made available and at least one side of the plate (1) is coated with plastic (3) at least in some areas in a primary molding process, so that at least the circuit board (1) and a plastic layer (6) are produced.

Description

The invention relates to a method for producing a composite component, as well as an assembly comprising a composite component produced by means of the method according to the invention, and a motor vehicle.

The fulfillment of legally anchored standards with regard to the electromagnetic compatibility (EMC) of devices requires components and assemblies that are designed in such a way that they are insensitive to electromagnetic interference from the environment and themselves emit sufficiently little electromagnetic interference. Proof of immunity to interference is regulated in the relevant standards. Such standards also apply to motor vehicles.

One way of implementing the requirements stipulated in the relevant standards is to design components and assemblies in such a way that they are electrically conductive. In the automotive industry, it is common practice to equip components with an electrically conductive layer, for example in the form of a conductive film. For this purpose, a metal foil is typically applied to the essentially completely shaped component. The often manual coating process for three-dimensional components that is associated with the subsequent application of a metal foil restricts the structural freedom when shaping the components.

The further processing possibilities of corresponding components are typically severely limited due to the metallic surface. For example, it is not easily possible in a cost-effective and process-reliable manner to attach connecting and / or stiffening elements to a component provided with a metallic surface.

An alternative procedure to the metallic coating consists in forming the corresponding components completely from a metallic material.

Composite components that include an electrically conductive layer are known in principle.

the DE 10 2014 016 329 A1 shows a composite component with a polymer extruded to form a foam layer, which forms the middle layer of a composite material and on which two facing layers are arranged opposite one another. The foam is placed between the cover layers and cooled together with the cover layers in a double belt press. After the composite component has cooled down, the foamed middle layer made of foam and the outer layers form a bond. At least one cover layer can be a metal sheet. A primer layer is arranged between the polymer and the metal sheet, which on the one hand adheres to the metal sheet and on the other hand to the polyamide.

The present invention is based on the object of providing a method which enables the production of a composite component in a simple and inexpensive manner, as well as providing an assembly and a motor vehicle which comprise such a composite component.

The object is achieved according to the invention by a method for producing a composite component according to claim 1, as well as by an assembly according to claim 9 and a motor vehicle according to claim 10. Advantageous embodiments of the method are shown in dependent claims 2-8.

A first aspect of the invention is a method for producing a composite component, in which a circuit board made of a metallic material is provided and at least one side of the circuit board is coated with plastic at least in some areas in a primary molding process, so that one having at least the circuit board and a plastic layer Layer composite is generated.

In the context of the invention, a circuit board is to be understood as an essentially two-dimensional flat component, such as a sheet metal or a film, for example. Typically, this is a development and / or cutting of a metallic material provided on rolls.

A metallic material is to be understood as a metal or a metal alloy.

In particular, the metallic material is characterized by high plasticity and / or high ductility, which makes it possible to deform the board, in particular in a loose or solid bond with another component, in a forming process without breaking or cracking the Board comes.

In one embodiment of the method, the metallic material is an aluminum or an aluminum alloy and / or a copper or a copper alloy.

According to the invention, at least one side of the circuit board is coated with a plastic. At least one plastic layer is applied here.

In a specific embodiment of the method, at least one side of the circuit board is essentially completely coated with plastic. This has the advantage that the circuit board is at least partially protected against damage from the outside, at least on the side coated with plastic.

In a further embodiment of the method, a first side of the circuit board and a second side of the circuit board opposite the first side are coated with plastic, so that the circuit board is essentially completely embedded in the plastic.

When the primary molding process is carried out, the blank and the plastic are mechanically connected to one another, with a cohesive and / or adhesive connection also being a mechanical connection within the meaning of the invention.

The plastic is, for example, polyolefins such as polypropylene (PP) or polycarbonate (PC). Polyamides are also possible.

The density of the plastic layer is at least 0.7 kg / m ³ .

When the primary molding process is carried out, the plastic is applied to one side of the board, in particular by means of a material flow that is essentially perpendicular to the surface of the board.

By means of the method according to the invention, a composite component can be produced in a simple manner, which is suitable for shielding an electrical and / or magnetic field arranged in the vicinity of the composite component, in particular in a motor vehicle, or an electrical engineering device.

In one embodiment of the method according to the invention, the primary molding method is an injection molding method.

The plastic is applied to the side of the circuit board as an essentially liquid plastic melt. This means that the plastic is liquefied and brought into mechanical contact with the circuit board in the liquid phase.

The advantage of this configuration is that there is great design leeway with regard to the structural configuration of the composite component.

In principle, other primary molding processes are also possible within the scope of the production process according to the invention for a composite component in order to apply the plastic to the circuit board and to coat it. Thus, an embodiment of the method using a 3D printing method as the original molding method is not ruled out. A pressure and / or shapeless casting process is also not excluded by way of example.

In one embodiment of the method according to the invention, the primary molding method is carried out in such a way that the plastic forms a three-dimensional structure extending away from the side of the circuit board.

This means that the three-dimensional structure of a body or profile formed by means of the plastic deviates significantly from a structure that only essentially extends two-dimensionally.

In a specific embodiment of the method according to the invention, at least one threaded connection element is connected to the plastic layer in a form-fitting and / or material-locking manner when the primary molding process is carried out. Furthermore, the threaded connection element can be formed by the plastic layer. This means in particular that a three-dimensional structure is formed and / or attached to the plastic layer applied to the circuit board, which structure is set up to be an element of a threaded connection, for example a screw dome. In one embodiment, the threaded connection element is initially formed on the plastic layer, for example by means of injection molding, a form-fitting and / or material-locking connection to the plastic layer being formed during the injection molding. Alternatively or additionally, a metallic thread element can be overmolded with plastic during the primary molding, the metallic thread element being positively and / or cohesively connected to the plastic layer. In this context, encapsulation is to be understood as meaning that the metallic threaded element is at least partially embedded in the plastic.

Furthermore, it can be provided that, as an alternative or in addition, at least one stiffening element is connected to the plastic layer in a form-fitting and / or material-locking manner when the primary shaping process is carried out. It is also possible for a stiffening element to be formed by the plastic layer. A stiffening element is to be understood as a shaped element which increases the flexural, buckling and / or torsional rigidity of the composite component.

In a specific embodiment of the method according to the invention, the three-dimensional structure is formed as a cast body by means of a negative mold which is at least partially filled with the plastic during the primary molding and which is removed from the composite component after the primary molding and at least partial solidification of the liquid plastic.

In a further specific embodiment of the method according to the invention, the three-dimensional structure is formed in layers, that is to say in layers which are successively built up on one another and connected to one another.

A combination of several primary shaping processes that are carried out simultaneously or one after the other for the purpose of forming the three-dimensional structure is not excluded according to the invention.

A composite component can thus be produced which deviates from an essentially two-dimensional flat shape and / or comprises shaped elements designed for the purpose of increasing the rigidity and / or providing connecting elements, for example.

In one embodiment of the method according to the invention, a first connecting substance is arranged between the circuit board and the plastic, which is set up to form a cohesive connection, in particular based on covalent bonds, with the circuit board and a cohesive connection with the plastic, in particular based on a chemical one Networking, training.

A material connection is understood to mean all connections in which the connection partners are held together by atomic or molecular forces. Cohesive connections are typically non-detachable connections. In the context of the invention, the material connection between the connecting substance and the circuit board on the one hand and the connecting substance and the plastic on the other hand realizes a mechanical connection between the circuit board and the plastic so that they are firmly connected to one another.

The first connection substance is set up to realize a material connection with the board based on covalent bonds. For this purpose, the first connecting substance comprises functional groups that can form a covalent bond with the metallic material of the board. It is not excluded that the functional groups can vary depending on the metallic material with which the integral connection is to be formed.

The first connection substance is also set up to realize a material connection with the plastic based on chemical crosslinking. Chemical crosslinking within the meaning of the invention means that molecules of the plastic form a three-dimensional network with molecules of the connecting substance. It is not excluded that a crosslinking reaction takes place, that is, that molecules of the plastic react chemically with molecules of the connecting substance.

In one embodiment of the method according to the invention, the first connecting substance comprises a polyamide, in particular a copolyamide, which has functional groups for forming, in particular, covalent bonds with the metallic material.

Furthermore, the polyamide is present as particles embedded in an essentially liquid or liquefiable carrier substance, the particle size of the particles of the polyamide being essentially less than 80 μm.

The first connection substance is applied to the circuit board, for example, by means of an electrostatic spray coating, at least in the area of the plastic coating to be carried out. The first connecting substance is applied to the circuit board before the primary molding process is carried out.

In addition, it is also possible for the first connecting substance to be applied to the circuit board as a film at least in the area of the plastic coating to be carried out.

In other words, the first connecting substance in this embodiment of the method is used to provide a mechanical connection between the circuit board and the plastic by means of an integral connection between the first connecting substance and the circuit board on the one hand and the plastic on the other hand. In this sense, the first connecting substance can also be referred to as an adhesion promoter between the circuit board and the plastic.

In one embodiment of the method according to the invention, at least the first connecting substance in the area in which the board is coated with plastic is heated to a temperature of at least 100 ° C, in particular of at least 150 ° C, for the purpose of forming a integral connection between the plastic and the first connecting substance.

At least the chemical crosslinking or the crosslinking reaction between the first connecting substance and the plastic is activated by the temperature. In other words, the temperature introduces energy in the form of heat into the first connecting substance, which triggers and / or accelerates the crosslinking or the crosslinking reaction.

Typically, the first connecting substance is heated by the fact that the plastic, which is liquefied by the supply of heat in the primary molding process, has a temperature of at least 100 ° C, in particular at least 150 ° C, when the board is coated, with heat from the plastic on contact between the plastic and the first connecting substance the first connecting substance is transferred, whereby the first connecting substance is heated.

It is not excluded that the area in which the circuit board is coated with plastic is alternatively or additionally heated by another energy or heat source, for example by means of a heat radiation source whose heat radiation is directed at the area to be coated.

Typically, the circuit board is also heated to a temperature of at least 100 ° C., in particular of at least 150 ° C., in the area in which the circuit board is coated with plastic.

The first connecting substance is activated by the supplied heat and thus the material connection between the circuit board and the plastic is formed.

Furthermore, the board has a thickness d _{P , which is in a ratio of d P} / d _{V, 1} to the thickness of a layer d _{V, 1 of} the first connecting substance between the board and the plastic, where essentially the following applies: d _P / d _{V, 1} > 1, especially d _P / d _{V, 1} > 2.

Process-related punctual deviations from this ratio are irrelevant.

In other words, the layer thickness of the first connecting substance is less than the thickness of the circuit board.

In particular, the board has a thickness d _P of at least 0.01 mm and at most 1 mm.

In other words, the circuit board can be designed as a film with a film thickness or thickness of at least 0.01 mm and at most 1 mm.

The thickness of the board is dimensioned so that the composite component to be produced has properties that shield against electromagnetic radiation, so that the composite component complies with current EMC guidelines, and at the same time the board can be easily deformed in a forming process, especially if the board is combined with another element is to be reshaped.

In one embodiment of the method according to the invention, the coating with the plastic is carried out in the original molding process on a first side of the board and the board is firmly connected to a plastic element, in particular to a plastic element comprising an organic sheet, on a second side opposite the first side.

The connection between the circuit board and the plastic element can take place before or after the first side of the circuit board is coated with the plastic.

The plastic element can in particular be a flat component.

The plastic element can comprise an organic sheet or be formed from such. An organic sheet is to be understood as a fiber composite material which comprises a fiber fabric or a fiber scrim that is incorporated into a typically thermoplastic plastic matrix. The fibers of the fiber fabric or fiber structure are typically, but not necessarily, made of glass, aramid or carbon. In other words, organic sheets are plastic elements that are reinforced with an optionally multi-layer fabric or scrim.

The connection between the second side of the circuit board and the plastic element can be formed in a manner analogous to the connection between the first side of the circuit board and the plastic. This means that a second connecting substance is arranged between the circuit board and the plastic element, which is set up to form a cohesive connection with the circuit board, in particular based on covalent bonds, and to form a cohesive connection with the plastic element, in particular based on chemical crosslinking, to train.

Typically, but not necessarily, the first connecting substance corresponds to the second connecting substance in terms of its chemical composition. However, it is possible that, for the purpose of forming the connection between the circuit board and the plastic element, one of the composition of the first connection substance different chemical composition is advantageous. This can be the case in particular if the material of the plastic layer and the material of the plastic element differ from one another.

Analogous to the formation of the mechanical connection between the circuit board and the plastic, the second connecting substance is heated in at least some areas to a temperature of at least 100 ° C, in particular at least 150 ° C, in order to form a material connection between the plastic element and the second connecting substance.

In a variant of the method according to the invention in accordance with this embodiment, the plastic element and the circuit board are mechanically connected to one another before the primary molding process is carried out.

In another variant of the method according to the invention according to this embodiment, the plastic element and the circuit board are mechanically connected to one another while the primary molding process is being carried out.

In particular, the plastic component extends essentially over the entire second side of the circuit board. In other words, the plastic element is covered by the circuit board essentially completely and essentially without interruption.

Furthermore, the board has a thickness d _{P , which is in a ratio d P} / d _{V, 2} to the thickness of a layer d _{V, 2 of} the second connecting substance between the board and the plastic, where essentially _: d _P / d _{V, 2} > 1, especially d _P / d _{V, 2} > 2.

In one embodiment of the method according to the invention, the thickness dp of the board to the thickness d _{K of} the plastic element is in a ratio d _P / d _K , where essentially: d _P / d _K <2, in particular d _P / d _K <1.

In a particular embodiment, d _P / d _K <0.5.

Process-related punctual deviations from the ratio are irrelevant.

In one embodiment of the method according to the invention, the plastic element is reshaped at least in certain areas together with the blank by means of a reshaping process before the primary shaping process is carried out.

This means that the plastic element and the circuit board are placed together in a forming tool and are formed at the same time, so that when the forming process is carried out, the plastic element and the circuit board are given complementary, in particular three-dimensional, shapes.

An exemplary forming process within the meaning of the invention is compression molding.

In this case, in a variant of the method according to the invention, the circuit board and the plastic element are or will be materially connected to one another before the primary shaping method is carried out.

In a second variant of the method, the plastic element and the board emerge from the forming process in a materially unconnected manner.

In none of the method variants of this embodiment of the method, it is impossible that during the forming process, alternatively or additionally, a form-fitting connection is formed between the plastic element and the circuit board.

The joint reshaping of the plastic element and the circuit board in one process step results in a corresponding saving of time in the manufacture of the composite component.

A second aspect of the invention is an assembly, in particular a housing assembly for a battery system of an at least partially electric motor-driven motor vehicle, comprising at least one composite component produced by the method according to the invention and at least one further, at least partially electrically conductive component, the composite component and the further component being electrically are conductively connected to each other.

In particular, the circuit board is connected to the further component in an electrically conductive manner.

This means that the assembly has a function that shields against electromagnetic radiation.

In addition, the composite component and the further component are mechanically connected to one another. The mechanical connection can be designed as a screw connection, for example.

By way of example, the assembly is a housing assembly of a battery system of a motor vehicle driven by an electric motor.

The further component can be a second composite component produced according to the method according to the invention.

Another aspect of the invention is a motor vehicle comprising at least one composite component produced by means of the method according to the invention and / or at least one assembly according to the invention.

The motor vehicle is in particular a motor vehicle driven at least partially by an electric motor.

The invention is explained below with reference to the exemplary embodiments shown in the accompanying drawings.

• 1: einen Ausschnitt einer ersten Ausgestaltungsform des mittels des erfindungsgemäßen Verfahrens hergestellten Verbundbauteils;
• 2: eine zweite Ausgestaltungsform eines mittels des erfindungsgemäßen Verfahrens hergestellten Verbundbauteils mit Versteifungselementen; sowie
• 3: eine dritte Ausgestaltungsform eines mittels des erfindungsgemäßen Verfahrens hergestellten Verbundbauteils mit einem Gewindeverbindungselement.

Show it

• 1 : a section of a first embodiment of the composite component produced by means of the method according to the invention;
• 2 : a second embodiment of a composite component with stiffening elements produced by means of the method according to the invention; as
• 3 : a third embodiment of a composite component produced by means of the method according to the invention with a threaded connection element.

1 shows a section of a first embodiment of the composite component produced by means of the method according to the invention 10 . It can be seen that the composite component 10 is built up in layers at least in the section shown and a layer composite 5 forms. On the first page 11 the board 1 is a plastic 3 arranged. Between the plastic 3 and the board 1 is a layer of a first compound substance 21 to recognize. On the second page 12th the board 1 is a plastic element 4th arranged. Between the board 1 and the plastic element 4th is a second compound substance 22nd to recognize.

According to one embodiment of the method according to the invention, during the production of the layer composite 5 of the composite component 10 initially on a plastic element 4th a circuit board 1 arranged. With the plastic element 4th In one embodiment, it is an organic sheet in the form of a fiber composite material, comprising a fiber fabric or a fiber scrim, which is embedded in a thermoplastic plastic matrix. At the board 1 it is, for example, an aluminum foil. Before attaching the board 1 on the plastic element 4th becomes the board 1 with the second connecting substance 22nd and typically also with the first connecting substance 21 coated. Subsequent to the attachment of the compound substances 21 , 22nd coated board 1 on the plastic element 4th becomes the plastic 3 using a primary molding process such as injection molding on the first side 11 applied and the board 1 thus with plastic 3 coated.

The connecting substances 21 , 22nd fulfill the function of an adhesion promoter in the method according to the invention.

Between the plastic element 4th and the board 1 is a second compound substance 22nd arranged. The second connecting substance 22nd is set up to have both a material connection to the plastic element 4th as well as to the board 1 to train.

Typically, but not necessarily, it is the first connecting substance 21 and the second connecting substance 22nd essentially the same compound substance.

2 shows a second embodiment of a composite component produced by means of the method according to the invention 10 . In the example shown here, they are attached to the composite by means of an injection molding process 51 comprising the plastic element 4th who have favourited the circuit board 1 and the compound substances 21 , 22nd four stiffening elements 13th molded on, which appear as three-dimensional structures from the first side 11 the board 1 extend away. According to the invention, the composite 51 before injection molding of the stiffening elements 13th have been deformed by means of a forming process.

3 shows a third embodiment of a composite component produced by means of the method according to the invention 10 . In the example shown here, the plastic element is attached to the by means of an injection molding process 4th who have favourited the circuit board 1 and the compound substances 21 , 22nd comprehensive network 51 a threaded fastener 14th , in the present example a screw dome.

List of reference symbols

1

circuit board

3

plastic

4th

Plastic element

5

Layer composite

6th

Plastic layer

10

Composite component

11

first page

12th

second page

13th

Stiffening element

14th

Threaded fastener

21

first compound substance

22nd

second compound substance

51

Composite

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102014016329 A1 [0007]

Claims (10)

A method for producing a composite component (10), in which a plate (1) made of a metallic material is made available and at least one side of the plate (1) is coated with plastic (3) at least in some areas in a primary molding process, so that at least the Board (1) and a layer composite (5) having a plastic layer (6) is produced. Method for producing a composite component (10) according to Claim 1 , characterized in that the primary molding process is an injection molding process. Method for producing a composite component (10) according to one of the preceding claims, characterized in that the primary molding process is carried out in such a way that the plastic (3) forms a three-dimensional structure extending away from the side of the blank (1). Method for producing a composite component (10) according to one of the preceding claims, characterized in that a first connecting substance (21) is arranged between the board (1) and the plastic (3), which is set up to connect to the board (1) to form a cohesive connection, in particular based on covalent bonds, and to form a cohesive connection with the plastic (3), in particular based on chemical crosslinking. Method for producing a composite component (10) according to Claim 4 , characterized in that when performing the primary molding process, at least the first connecting substance (21) in the area in which the circuit board (1) is coated with plastic (3) to a temperature of at least 100 ° C, in particular of at least 150 ° C is heated in order to form a material connection between the plastic (3) and the first connecting substance (21). Method for producing a composite component (10) according to one of the preceding claims, characterized in that the coating with the plastic (3) in the primary molding process is carried out on a first side (11) of the board (1) and the board (1) on a the second side (12) opposite the first side (11) is firmly connected to a plastic element (4), in particular to a plastic element (4) comprising an organic sheet. Method for producing a composite component (10) according to Claim 6 , characterized in that the thickness dp of the plate (1) to the thickness d _{K of} the plastic element (4) is in a ratio d _P / d _K , where essentially: d _P / d _K <2, in particular d _P / d _K <1. Method for producing a composite component (10) according to one of the Claims 6 - 7th , characterized in that the plastic element (4) together with the blank (1) is reshaped at least in certain areas by means of a reshaping process before the primary shaping process is carried out. Assembly, in particular a housing assembly for a battery system of a motor vehicle driven at least partially by an electric motor, comprising at least one composite component (10) produced by a method according to one of the Claims 1 - 8th and at least one further at least partially electrically conductive component, the composite component (10) and the further component being connected to one another in an electrically conductive manner. Motor vehicle comprising at least one composite component (10) produced by the method according to Claims 1 - 8th and / or at least one assembly according to Claim 9 .

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