WO2023214032A1

WO2023214032A1 - Method for producing a laminar composite, and laminar composite

Info

Publication number: WO2023214032A1
Application number: PCT/EP2023/061974
Authority: WO
Inventors: Bernhard SCHERUEBL
Original assignee: Elringklinger Ag
Priority date: 2022-05-05
Filing date: 2023-05-05
Publication date: 2023-11-09
Also published as: DE102022111207A1

Abstract

The invention relates to a method for producing a laminar composite (102) of a laminar-composite semi-finished product or of a laminar-composite structural component (100), wherein a layer arrangement (106) is provided comprising a reinforcement layer (110, 120), e.g. a fibre-reinforced reinforcement layer, and a polymer layer (130) arranged on a surface of the reinforcement layer, wherein the polymer layer (130) comprises a thermoplastic polymer material (131), the layer arrangement (106) is transformed into a laminar composite (102) by heating, in which laminar composite the polymer layer (130) has a deformable polymer layer (132), and the form of the laminar composite (102) is changed by applying force.

Description

Method for producing a layered composite and layered composite

The present invention relates to the technical field of producing reinforced layered composites and structural components which are partly formed from polymers.

Layered composite-based structural components are installed, for example, in motor vehicles below traction batteries and are used in particular for intrusion protection, i.e. to protect a traction battery from mechanical damage that can be caused by impacting objects while driving.

To produce layered composite structural components, fiber-reinforced reinforcement layers can first be pretreated in an oven. With two reinforcement layers removed from the oven and cooled and a polymer material introduced between them, a sandwich composite can then be produced and converted into a sandwich structural component that has a desired shape in a forming tool with heating and, if necessary, subsequent processing steps.

During forming, heat is supplied via the outer surfaces of the reinforcement layers. As a result, the polymer introduced in between is heated to a target temperature suitable for forming. The reinforcement layers generally become hotter than the polymer core of the resulting layer composite. If a specific target temperature that is favorable for forming is to be set in the polymer core, the reinforcement layers must be exposed to a higher thermal load peak than the polymer core itself. In addition, the temperature in the core area rises more slowly, especially in thick layer composites, so that the target temperature that is favorable for forming is reached there is not achieved or only achieved very slowly. A homogeneous heating of the core area with at the same time low thermal load on the reinforcement layers on the outer surfaces can only be achieved through a very slow supply of heat and thus a very slow and therefore inefficient process management.

The procedure described involves a great deal of effort, particularly when complex layer composite-based structural components of uneven thickness are to be produced. The polymer core can then be heated evenly be bought with a lot of time and effort by slowly, evenly heating the entire layered composite with uniform heat input in thick and thin areas of the layered composite. As a result, approximately the same temperature is reached everywhere in the polymer core area at some point. The high expenditure of time can only be avoided with a high level of technical effort if heating elements of a forming tool are designed with great technical effort in such a way that a higher heat input occurs in thick areas of the layered composite.

The present invention is based on the object of making a layered composite and semi-finished products and structural components based thereon accessible with as little time and technical effort as possible.

The object is achieved according to the invention by the features of claim 1. There, a method for producing a layered composite, a layered composite semi-finished product or a layered composite structural component is specified, wherein a layer arrangement is provided, comprising a reinforcing layer, for example a fiber-reinforced reinforcing layer, and a polymer layer arranged on a surface of the reinforcing layer, the polymer layer comprising a thermoplastic polymer material, which Layer arrangement is converted into a layered composite by heating, in which the polymer layer comprises a deformable polymer layer, and the shape of the layered composite is changed by the application of force.

The term layered composite is used as a general term in connection with the invention. This general term also includes the layered composite semi-finished product and the layered composite structural component.

A layered composite semi-finished product is considered in particular to be a product that is obtained after the application of force and has a changed shape as a result of the application of force.

A layered composite structural component is considered in particular to be a component that can be obtained from a layered composite semi-finished product by post-processing. The post-processing can include, for example, the attachment of connection points via which the layered composite structural component can be connected to other components, for example on or in the area under a traction battery of a motor vehicle. The connection points can include, for example, holes through which fasteners, such as bolts, can extend.

The term layer arrangement refers here in particular to an arrangement of layers, i.e. the reinforcing layer and the polymer layer. The layers are typically not bonded together until heated. This is because a connection of the layers is achieved during heating, among other things, by the polymer layer comprising a deformable polymer layer as a result of the heating. Typically, the polymer layer melts completely or partially and the melted polymer material adheres to the surface of the reinforcing layer. However, the term layer arrangement also includes arrangements in which the polymer layer adheres to the reinforcing layer before heating. In general, heating then increases the adhesion of the polymeric material of the polymeric layer to the reinforcing layer.

Any layer that can be used to reinforce the polymer layer, that can withstand heating and that can be deformed by force after heating can be considered as a reinforcing layer. The reinforcement layer can be a fiber-reinforced reinforcement layer.

The reinforcing layer, e.g. the fiber-reinforced reinforcing layer, may also comprise a polymer material. The polymer material comprised by the reinforcing layer can preferably be a thermoplastic or a resin.

The thermoplastic comprised by the reinforcing layer can preferably contain a polypropylene (PP), a polyamide (PA) or a polybutylene terephthalate (PBT) or combinations of at least two of these thermoplastics.

The resin comprised by the reinforcing layer may preferably contain a polyurethane resin, a polyamide resin or a combination of these resins.

The reinforcing layer can, for example, be a fiber-reinforced reinforcing layer and the polymer material comprised by the reinforcing layer can be in contact with surfaces of fibers of the reinforcing layer. The fibers can, for example, be embedded in the polymer material comprised by the reinforcing layer, be impregnated with the polymer material or be arranged on a surface of the polymer material. The fibers of the fiber-reinforced reinforcement layer can run unidirectionally. The fiber-reinforced reinforcing layer can, for example, comprise a unidirectional fiber fabric.

The fibers of the fiber-reinforced reinforcement layer can run multidirectionally. The fiber-reinforced reinforcing layer can, for example, comprise a multidirectional, in particular bidirectional fiber fabric or a fiber fabric.

The fiber-reinforced reinforcing layers can comprise one or more, for example 1 to 10, fiber layers.

The fibers of the fiber-reinforced reinforcing layer can be polymer fibers, e.g. aramid fibers, polyacrylonitrile fibers, partially oxidized polyacrylonitrile fibers; Carbon fibers and/or mineral fibers, e.g. glass fibers, included.

At least some of the glass fibers can preferably be hollow gas fibers or glass fibers made from E-glass, R-glass or quartz glass.

The meanings of the terms E-glass and R-glass are known to those skilled in the art.

The polymer layer comprises a thermoplastic polymer material. The term thermoplastic can in particular mean that it melts completely or partially when heated and, after the shape of the layered composite has been changed by the force, solidifies again when it cools down later. The thermoplastic polymer material comprised by the polymer layer can contain, for example, polyamide (PA), polyphthalamide (PPA), polypropylene (PP) or polyethylene (PE), whereby the following additives can optionally be provided: short and/or long fibers made of carbon and/or glass , mineral components, ceramic components, lubricants. The mass fraction of the additives is in particular at least approximately 40%, for example at least approximately 50%, and/or at most approximately 80%, for example at most approximately 70%. In particular, the mass fraction of the additives is approximately 60%.

The thermoplastic polymer material comprised by the polymer layer can be foamable. The thermoplastic polymer material can be chemically or physically foamable. During chemical foaming, a substance, such as CO2, can be released through a chemical reaction. The resulting gas bubbles foam up the thermoplastic polymer material.

During physical foaming, gas bubbles are formed from a volatile substance dispersed in the thermoplastic polymer material, e.g. N2, which foam the thermoplastic polymer material.

According to the invention, the layer arrangement is converted by heating into a layer composite in which the polymer layer comprises a deformable polymer layer. Preferably, the layer arrangement is converted by heating into a layer composite in which the polymer layer is a deformable polymer layer. Those skilled in the art will know that different thermoplastic polymer materials melt at different temperatures. The person skilled in the art selects the temperature to which the polymer layer should be heated during heating so that the formability of the resulting polymer layer is sufficient to achieve a desired shape of the layer composite, which is to be adjusted during the later application of force.

According to the invention, the shape of the layered composite is changed by the application of force. This can be done in a shaping tool, for example by extrusion, compression molding and/or thermoforming, preferably by extrusion and/or compression molding. In general, at least the shape of the polymer layer and preferably also the shape of at least one reinforcing layer are changed.

The shaping tool can be designed with or without a temperature control element. The shaping tool is preferably designed with a temperature control element. The temperature control element can be used to adjust the temperature of the surfaces of the shaping tool, which come into contact with surfaces of the layer composite until the force is applied.

The temperature control element can be a temperature control element through which a temperature control medium can be guided. It can be used in particular for heating. The method can preferably be used to produce a sandwich layer composite, a sandwich layer composite semi-finished product or a sandwich layer composite structural component, the layer arrangement provided being a sandwich layer arrangement in which the polymer layer is arranged between the reinforcing layer and a further reinforcing layer.

The further reinforcing layer can preferably be designed as described herein for the said reinforcing layer.

It may be preferred if the heating takes place in a connecting tool and the shape of the layer composite is changed in a shaping tool. The connecting tool and the shaping tool are preferably spatially separated.

This can have significant benefits. The connecting tool, which can be, for example, an oven, and the shaping tool can be operated at different temperatures. In particular, the connecting tool can be operated at a higher temperature than the shaping tool.

It is conceivable that the shaping tool, e.g. after an initial heating of the shaping tool, is supplied only with the heat that is given off by the layer composite to the shaping tool.

When the layered composite is transferred from the connecting tool to the shaping tool, a surface of the layered composite that comes into contact with the surrounding air can approach the lower temperature at which the shaping tool is operated.

It is preferred if the surface of the layered composite cools by YK based on the surface temperature that occurs during heating. Y is preferably at least 5%, in particular at least 10%, for example at least 15%, of the temperature difference between the surface temperature of the layered composite, which occurs during heating, and the temperature of the ambient air. The temperature of the ambient air can be determined in the room in which the method according to the invention is carried out. In the layered composite, a temperature gradient can arise when the layered composite is transferred from the connecting tool to the shaping tool, with the temperature inside the layered composite being higher than on a surface of the layered composite.

At the start of the application of force to change the shape of the layer composite, a temperature inside the layer composite, for example in the interior of the polymer layer, can be higher (preferably at least 5 K, particularly preferably at least 15 K, for example at least 30 K higher) than on a surface of the Layer composite. This can lead to the shape of the layer composite being significantly changed by the force despite its relatively low surface temperature. Because of the increased temperature inside the layered composite, the polymer layer is softer than would be expected given the surface temperature of the layered composite.

It would be conceivable, for example, that when the force begins to change the shape of the layered composite, a temperature inside the polymer layer is more than 220 ° C and is therefore higher than a temperature on a surface of the layered composite, which is, for example, less than 210 ° C.

The person skilled in the art can adjust the temperatures inside and on the surface within the scope of the invention, taking into account the melting temperature of the polymer material used, so that shaping is possible and a stable layer composite is obtained.

This opens up the possibility of operating the shaping tool at a relatively low temperature and changing the shape of the layer composite by applying force at a moment in which the temperature inside the layer composite, in particular in the interior of the polymer layer, is higher than the temperature at which the shaping tool is operated.

The temperature at which the shaping tool is operated can be considered to be an average temperature of the surfaces of the shaping tool, which come into contact with surfaces of the layer composite until the end of the force action. This temperature is also referred to herein as the mean mold temperature. It can be adjusted on a shaping tool with a temperature control element via the temperature control element.

The average shaping tool temperature can be, for example, at least 20 °C, preferably 20 °C to 90 °C. The range from 20 °C to 90 °C is particularly advantageous because a shaping tool can be heated without pressure using water in this temperature range.

The connecting tool temperature can advantageously be 140 ° C to 300 ° C, preferably 180 to 280 ° C. This means that the optimal processing temperatures of many polymer materials (PP: 200 °C to 240 °C, PA: 260 °C to 280 °C) can be achieved by appropriately adjusting the residence times in the connecting tool.

An adaptation temperature difference AT, which is calculated by subtracting the average shaping tool temperature from the connecting tool temperature, can be at least 5 K, preferably at least 10 K, in particular at least 15 K, for example at least 40 K.

In a previously common operation of a shaping tool, heat was introduced from a surface of a shaping tool into the polymer layer via a reinforcing layer and then formed under the action of force. The shaping tool was also used to heat up an introduced layer arrangement. In order to bring about heating quickly, especially with thicker layer arrangements, the shaping tool was kept at a temperature above the desired forming temperature of the polymer layer or polymer layer. At the moment the force was applied, the temperature of the reinforcing layer was typically higher than the temperature in the polymer layer or polymer layer. The temperature gradient in the layered composite at the moment of forming was therefore the opposite of the temperature gradient that can be adjusted using the process management according to the invention.

A preliminary heating according to the invention in the connecting tool, for example in an oven, can take place over a longer period of time, which can be 1 to 120 minutes, preferably 2 to 90 minutes. Finally, the layer arrangement takes place Don't use an expensive shaping tool at this moment. A thermal load peak on the reinforcement layer can be mitigated because the operating temperature of the connecting tool can be set approximately to the target temperature at which the downstream force should be applied. This has the decisive advantage that relatively heat-sensitive reinforcement layers, which can include heat-sensitive polymer materials, for example, can also be formed in combination with high-melting polymer layers.

A typical joining tool has one or more heating zones in which heating occurs.

The connection tool can be an oven and the heating zone can be an oven chamber.

The connecting tool can be heated in stages. The bonding tool may be a multi-stage forced air oven or may include a multi-stage forced air oven.

The connection tool may be a two-zone convection oven or may include a two-zone convection oven.

Different temperatures can prevail in different zones in the connecting tool. Then the temperature in the zone that is last reached in the course of heating in the joining tool is considered the joining tool temperature.

The connecting tool can be accessible on one side or accessible on two sides.

The connecting tool can be a continuous connecting tool accessible from two sides, through which the layer arrangement is guided and thereby converted into the layer composite by heating.

The guidance can be effected by a conveyor device.

It can be advantageous to convey the layer arrangement into the heating zone with a conveyor device and to convey the layer composite obtained after heating out of the heating zone with the conveyor device. The conveyor device can include, for example, a needle conveyor, a transport robot and/or a needle gripper.

A typical shaping tool has a shaping zone in which the shape of the layer composite obtained from the connecting tool is changed.

It can be advantageous if at least one conveyor device conveys the layer composite from the connecting tool to the shaping tool. It can be particularly advantageous if the conveying device takes over the layer composite conveyed by the conveying device from the connecting tool and conveys it into the shaping tool.

The conveyor device can have spacer elements. This can have the effect that only the surface areas of the heated layer composite adjacent to the spacer elements come into physical contact with the conveyor device. This can reduce the risk of uncontrolled adhesion of the heated layer composite to the conveyor device. Uncontrolled adhesion of the heated layered composite to the conveyor device would make it more difficult to introduce the layered composite into the shaping zone. The number of spacer elements is preferably at least 3. The spacer elements can, for example, be shaped in such a way that they rest on a maximum of 10%, for example a maximum of 3%, of a surface of the layered composite facing the conveyor device and the remaining areas keep this surface of the layered composite at a distance from the conveyor device. The spacer elements can be needle-shaped, for example.

The conveyor device can, for example, comprise a conveyor arm or a conveyor belt. The conveying device, in particular the conveying arm, can comprise a layered composite holding device, for example a needle gripper.

The layered composite holding device, e.g. the needle gripper, can have the spacer elements, which can be needle-shaped, for example.

The layer composite conveyed from the connecting tool can be needled by the conveyor device. This can mean in particular that the layer composite is gripped using at least one needle gripper. The shaping tool can also have spacer elements, for example at least 3 spacer elements. The layer composite can initially be placed on these spacer elements by the conveyor device. It can be advantageous if the spacer elements extend from a surface of a mold half of the shaping tool and are designed so that they are movable relative to the surface of the mold half. They can preferably be accommodated in the mold half. These spacer elements can be, for example, pin elements that are guided in guides. They are preferably guided in the guides in such a way that the pin elements can be completely accommodated in the guides.

It can be advantageous if there is no active cooling of the layer composite between the connecting tool and the shaping tool. This means in particular that cooling occurs only through the surrounding air. Of course, the surrounding air can be circulated and/or cooled.

A temperature adaptation time t, which elapses from the removal of the layer composite from the connecting tool to the introduction of the layer composite into the shaping tool, can be up to 150 seconds, preferably up to 50 seconds, further preferably up to 15 seconds, particularly preferably up to 10 seconds. e.g. up to 5 seconds. This can have the advantage that the temperature inside the layered composite remains sufficiently high for a subsequent change in the shape of the layered composite under the force. Shaping is then possible with the least possible expenditure of time and effort.

An adaptation temperature gradient G, which is calculated by dividing the adaptation temperature difference AT by the temperature adaptation time t, can be in a range from 0.005 to 50 K/s, preferably in a range from 0.01 to 45 K/s, particularly preferably in a range from 0.02 to 40 K/s, for example in a range from 0.05 to 35 K/s.

In view of the above statements, it can be advantageous if the heating conditions during heating and the temperature adaptation conditions are coordinated with one another in such a way that a temperature inside the deformable polymer layer has a surface temperature of the layer composite when the layer composite is introduced into the shaping tool by at least 5 K, for example at least 20 K, exceeds. The heating conditions during heating are understood to mean, for example, the duration and the temperature during heating. The temperature adaptation conditions are understood to mean, for example, the temperature of a medium extending around the layered composite, in particular air, and the temperature adaptation time in this medium from the removal of the layered composite from the connecting tool to the introduction of the layered composite into the shaping tool.

In the method according to the invention, which enables the shaping tool to be operated at relatively low temperatures, the inherent tendency for the layer composite to adhere to a surface of the shaping tool is lower than in other processes. Auxiliary substances that counteract sticking in molding tools can therefore be omitted in whole or in part. The production capacity can therefore be increased. This is because operational interruptions to introduce such auxiliary materials into the shaping tool can be completely or partially eliminated.

According to the invention, the layer arrangement can be provided without prior heating of the reinforcing layer or layers.

While it was common practice to heat different layers separately to form a layered composite and then bring them together to form a composite, the invention makes it possible to form the entire layer arrangement without separately heating the individual layers and to heat the layers together in the layer arrangement. Of course, this does not rule out the layer arrangement being constructed from preheated layers.

When heated, the surface of the layer arrangement can reach a temperature of at least 5 K, in particular 6 K to 100 K, for example 10 K to 60 K, above the melting temperature of the polymer material contained in the polymer layer. This can make it possible, particularly with heat-insensitive reinforcement layers, to carry out heating very quickly and thereby further increase the efficiency of the process.

When reference is made herein to a melting temperature, what is meant is the melting temperature determined in accordance with EN ISO 11357-3:2018 by dynamic differential thermal analysis (DSC). At the start of the application of force to change the shape of the layered composite, a temperature inside the layered composite can be at or above, preferably above, the melting temperature of the polymer material comprised by the polymer layer and a temperature on a surface of the layered composite can be at or below the melting temperature of the Reinforcement layer included polymer material lie. The temperature in the transition from the polymer layer to the reinforcing layer is also preferred at or above the melting temperature of the polymer material comprised by the polymer layer.

This can advantageously make it possible for the shape of the layered composite to be easily changed under the action of force. At the same time, adhesion of a surface of the layer composite to the shaping tool can advantageously be avoided.

According to the invention, the polymer material comprised by the reinforcing layer can, for example, correspond to the polymer material comprised by the polymer layer.

The previous heating and the subsequent partial (e.g. passive) cooling during transfer into the shaping tool can create a temperature gradient. The temperature on a surface of the layered composite can therefore be lower than a temperature inside the layered composite.

This can advantageously enable the shape of the layered composite to be changed with little effort and largely prevent the layered composite from sticking to the shaping tool.

The invention can therefore be used to obtain layered composite semi-finished products and layered composite structural components with a uniform polymer matrix, the polymer matrix extending through several layers and comprising the same polymer material.

The melting temperature of a polymer material included in the reinforcing layer may be lower than the melting temperature of a polymer material included in the reinforcing layer. This applies in particular when a melt of the first polymer material encompassed by the reinforcing layer that forms during heating adheres to fibers of the reinforcing layer and in particular does not drip off. So can for them Melting temperature Tsv of a polymer material included in the reinforcing layer applies:

Ts > TSP - X where TSP is the melting temperature of the polymer material comprised by the polymer layer and

The polymer layer can be foamable.

The shaping step may include foaming at least a portion of the polymer layer. The term shaping step refers to the change in the shape of the layer composite due to the effect of force.

The foaming of the area can advantageously be promoted by a force which moves the two surface areas of the polymer layer adjacent to this area away from one another.

For example, the foaming of the area can occur within a molding tool that includes a first and a second mold half and the external force can be applied by removing at least a portion of one mold half from at least a portion of the other mold half.

The object is also achieved according to the invention by a layer composite, which is preferably obtainable by a method according to the invention, wherein the polymer layer can have a porous layer area.

The object is also achieved according to the invention by a layered composite semi-finished product, which is preferably obtainable by a method according to the invention, wherein the polymer layer can have a porous layer area.

The object is also achieved according to the invention by a layered composite structural component, which is preferably obtainable by a method according to the invention, wherein the polymer layer can have a porous layer region. Preferably, the porous layer region can be spaced apart from the reinforcing layer and can have a lower density than a region of the polymer layer lying between the porous layer region and the reinforcing layer. The density can be determined by cutting and weighing defined polymer layer volumes from the porous layer area and from the area lying between the porous layer area and the reinforcing layer. The determined mass is then divided by the respective polymer layer volume.

Of course, features described in connection with the method according to the invention can also form features of the layered composite according to the invention, the layered composite semi-finished product according to the invention or the layered composite structural component according to the invention.

Further preferred features and/or advantages of the invention are the subject of the following description and the graphic representation of exemplary embodiments.

Shown in the drawings:

1 shows a schematic representation of a method according to the invention;

Fig. 2 is a schematic sectional view of a layer arrangement from Fig. 1;

Fig. 3 is a schematic representation of a connecting device from Fig. 1, which contains the layer arrangement shown in Fig. 2;

4 shows a schematic representation of a shaping device which contains a layer composite that can be shaped therein; and

Fig. 5 is a schematic representation of a complex shaped layered composite structural component.

Identical or functionally equivalent elements are provided with the same reference numbers in all figures. Fig. 1 shows schematically a method for producing a layer composite. A layer arrangement 106 is provided, which is shown in more detail in FIG. 2. It includes two reinforcement layers 110 and 120. These are fiber-reinforced reinforcement layers. The layer arrangement 106 also includes a polymer layer 130 between the two reinforcement layers 110 and 120. The polymer layer includes a polymer material 131.

The reinforcing layers each also include a polymer material 133. The polymer material 133 is in contact with surfaces of fibers of the respective reinforcing layer.

On a support grid 184, the layer arrangement 106 is introduced into the connecting device 180, also shown in FIG. 1. The connection device 180 may be an oven. The layer arrangement 106 is converted into a layer composite 102 by heating. In the layered composite, the polymer layer 130 comprises a deformable polymer layer 132, which connects the reinforcing layers 110 and 120.

The layer composite 132 is then introduced into a mold half 192 of a shaping tool 190 by a conveyor device 200 and the shape of the layer composite 132 is changed therein by the action of force, as indicated in FIG. 4.

Between the connecting tool 180 and the shaping tool 190, in particular while the layer composite 102 is in contact with the conveyor device 200, there is no active cooling of the layer composite 102. Cooling essentially only occurs by releasing heat into the air surrounding the layer composite.

The average shaping tool temperature can be, for example, 85 °C. The connecting tool temperature can be, for example, 181 °C. The adaptation temperature difference AT is then 96 K. The surrounding air cools down the surface of the layered composite, which is initially around 181 °C, quite quickly.

At 181 ° C, the surface of the layer arrangement 106 reaches a temperature of slightly more than 10 K above the melting temperature of the polymer material 131 contained in the polymer layer 130 when heated. It can take, for example, 9 seconds from the time the layer composite 102 is removed from the connecting tool 180 until the layer composite 102 is introduced into the shaping tool 190. The temperature adaptation time t is therefore 9 seconds.

The adaptation temperature gradient is therefore 10.67 K/s.

When the force begins to change the shape of the layered composite 102 in the shaping tool, the temperature inside the polymer layer 132 can be significantly higher than on a surface of the layered composite 102. While the surface of the layered composite cools quickly in the ambient air, the temperature inside the polymer layer remained 132, which was not directly exposed to the ambient air, was significantly higher during the 9 seconds. The core temperature in the deformable polymer layer of approximately 181 ° C can exceed a surface temperature of the layer composite 102 by approximately 10 K when the layer composite 102 is introduced into the shaping tool 190.

FIG. 2 shows the layer arrangement 106 from FIG. 1 more clearly. It is a sandwich layer arrangement 107 in which the polymer layer 130 is arranged between the reinforcement layers 110 and 120. The method shown in FIG. 1 is therefore a method for producing a sandwich layer composite.

3 shows, the heating in the connecting tool 180 in the example shown here is carried out by heating elements 182. The heating elements 182 can be heat radiators. The connection tool could also be a forced air oven instead. The support grid 184 has been omitted in FIG. 3. When heating, the temperature and duration in the example shown are selected so that the polymer material 131 of the polymer layer 130 melts at least enough to bond to the adjacent surfaces of the reinforcing layers 110 and 120.

Fig. 4 shows the layer composite 102 in the mold half 192, into which it was introduced by the conveyor device 200. In addition, another mold half 194 of the shaping tool 190 is shown. The two surfaces of the two mold halves 192 and 194 facing the layered composite 102 define the shape that is assumed by the layered composite 102 during the subsequent shaping under the action of force in the closed shaping tool 190. From the shaping in the shaping tool 190, a sandwich layer composite semi-finished product is obtained, from which a sandwich layer composite structural component can be obtained by post-processing. This can be, for example, a layered composite structural component that is suitable for mounting on a motor vehicle below a traction battery.

5 illustrates that a (sandwich) layer composite 102, 103 available in this way or a (sandwich) layer composite structural component 100, 101 available in this way can have complex shapes. At least a part of the sandwich layer composite structural component 101 can, for example, form a cover, a bottom or a wall of a housing, in particular a housing of an energy storage device, for example a battery or a tank.

The structural component 101 shown in Fig. 5 comprises different areas, each with a polymer layer 132, each comprising an expanded, porous layer area 134, as well as two reinforcement layers 110 and 120.

In the highly expanded layer composite area 129, additional reinforcement layers 112 and 122 are arranged on the reinforcement layers 110 and 120.

In other layer composite areas 127 and 128, only reinforcing layers 110 and 120 are arranged. In particular in layer composite area 127, in which there is no polymer layer 132 at all, but also in weaker expanded porous layer composite areas 128, in which the polymer layer 132 has a smaller proportion of pores than in more strongly expanded porous layer composite areas 129, no additional reinforcement layers 112 and 122 are attached in the example shown here .

The structural component shown in FIG. 5 can be obtained with a polymer layer 132 that is foamable. The shaping step, ie changing the shape of the layer composite 102 by applying force in the shaping tool 190, includes foaming in the layer composite areas 128 and 129 of the polymer layer 132. The foaming of the layer composite areas 128 and 129 is promoted by a force which moves the two to these layer composite areas 128 and 129 adjacent surface areas of the polymer layer 132 are spaced apart. The foaming of the layer composite areas 128 and 129 takes place within the shaping tool 190, which includes a first and a second mold half 192 and 194, the external force being applied by removing at least a part of one mold half 194 from the other mold half 192.

Ribs 123 can be formed on at least one surface of a reinforcing layer 122. The surface of the reinforcing layer 120 may also include tethered elements 125.

Reference symbol list

Layered composite structural component 100

Sandwich layered composite structural component 101

Layer composite 102

Sandwich layer composite 103

Layer arrangement 106

Sandwich layer arrangement 107

Reinforcement layer 110

Additional reinforcement layer 112

Reinforcement layer 120

Additional reinforcement layer 122

Rib 123 attached element 125 unexpanded layer composite area 127 expanded layer composite area 128 strongly expanded layer composite area 129

Polymer layer 130

Polymer material 131

Polymer layer 132

Polymer material 133 porous layer area 134

Connection tool 180

Heating element 182

Wear rust 184

Shaping tool 190

Mold half 192

Mold half 194

Conveyor device 200

Claims

Claims Method for producing a layered composite (102), a layered composite semi-finished product or a layered composite structural component (100), wherein a layer arrangement (106) is provided, comprising a

Reinforcing layer (110, 120), for example a fiber-reinforced reinforcing layer, and a polymer layer (130) arranged on a surface of the reinforcing layer, the polymer layer (130) comprising a thermoplastic polymer material (131), the layer arrangement (106) being converted into a layer composite by heating ( 102) is transferred in which the polymer layer (130) comprises a deformable polymer layer (132), and the shape of the layer composite (102) is changed by the action of force. Method according to claim 1 for producing a sandwich layer composite (103), a sandwich layer composite semi-finished product or a sandwich layer composite structural component (101), wherein the layer arrangement (106) provided is a sandwich layer arrangement (107) in which the polymer layer (130) is arranged between the reinforcing layer (110, 120) and a further reinforcing layer (110, 120). Method according to claim 1 or 2, wherein the heating takes place in a connecting tool (180) and the shape of the layer composite is changed in a shaping tool (190). Method according to claim 3, wherein there is no active cooling of the layer composite (102) between the connecting tool (180) and the shaping tool (190). A method according to claim 3 or 4, wherein an adaptation temperature difference AT, which is calculated by subtracting the average forming tool temperature from the connecting tool temperature, is at least 5 K, for example at least 40 K. Method according to one of claims 3 to 5, wherein the temperature adaptation time t, which is required by removing the layer composite (102) from the connection Tool (180) takes up to 150 seconds until the layer composite (102) is introduced into the shaping tool (190). Method according to one of claims 3 to 6, wherein the adaptation temperature gradient G, which is calculated by dividing the adaptation temperature difference AT by the temperature adaptation time t, is in a range of 0.005 to 50 K/s. Method according to one of the preceding claims, wherein at the start of the application of force to change the shape of the layer composite (102), a temperature inside the layer composite (102), for example in the interior of the polymer layer (132), is higher than on a surface of the layer composite (102 ). Method according to one of the preceding claims, wherein the heating conditions during heating, for example the duration and the temperature during heating, and the temperature adaptation conditions, for example the temperature of a medium extending around the layer composite (102), in particular air, and the temperature adaptation time in this medium from the removal of the layered composite (102) from the connecting tool (180) to the introduction of the layered composite (102) into the shaping tool (190) so that a temperature inside the deformable polymer layer (132) corresponds to a surface temperature of the layered composite (102). Introduction of the layer composite (102) into the shaping tool (190) exceeds by at least 5 K, for example at least 20 K. A method according to any one of the preceding claims, wherein the layer arrangement (106) is provided without prior heating of the reinforcing layer (110, 120). Method according to one of the preceding claims, wherein the surface of the layer arrangement (106) has a temperature of at least 5 K, e.g

10 K to 100 K, above the melting temperature of the polymer material (131) contained in the polymer layer (130). A method according to any one of the preceding claims, wherein the reinforcing layer also comprises a polymeric material (133). The method of claim 12, wherein the reinforcing layer (110, 120) is a fiber-reinforced reinforcing layer and the polymeric material (133) comprised by the reinforcing layer is in contact with surfaces of fibers of the reinforcing layer. Method according to one of claims 12 or 13, wherein at the start of the application of force to change the shape of the layered composite (102), a temperature inside the layered composite (102) is at or above, preferably above, the melting temperature of the polymer material (131) comprised by the polymer layer. and a temperature on a surface of the layer composite (102) is at or below the melting temperature of the polymer material (133) comprised by the reinforcing layer (110, 120). Method according to one of claims 12 to 14, wherein the following applies to the melting temperature Tsv of a polymer material (133) comprised by the reinforcing layer (110, 120):

Tsv ^> TSP - 20K where TSP is the melting temperature of the polymer material (131) comprised by the polymer layer (132). A method according to any one of the preceding claims, wherein the polymer layer (132) is foamable and the shaping step comprises foaming at least a portion of the polymer layer (132). The method of claim 16, wherein the foaming of the region is promoted by a force which separates the two surface regions of the polymer layer (132) adjacent to said region. The method of claim 17, wherein foaming the area occurs within a forming tool (190) having a first and a second Mold half (192, 194), and the external force is applied by removing at least part of one mold half (192, 194) from at least part of the other mold half (192, 194). Layer composite (102), layer composite semi-finished product or layer composite structural component (101), preferably obtainable according to one of the methods of claims 1 to 18, wherein the polymer layer (132) has a porous layer region (134). Layered composite (102), layered composite semi-finished product or layered composite structural component (100) according to claim 19, wherein the porous layer region (134) is spaced from the reinforcing layer (110, 120) and has a lower density than one lying between the porous layer region (134) and the reinforcing layer Area of the polymer layer (132).