EP2554708A1 - Method for producing a metallic workpiece with at least one cavity - Google Patents

Abstract

The method involves positioning a polymer profile (5) on a substrate (1). The polymer profile is encapsulated with metallic particles (3) by thermal spraying process. The polymer profile is released partially and the cavity is left in the workpiece after triggering polymer profile.

Description

The invention relates to a method for producing a metallic workpiece with at least one cavity.

A cavity here means both cavities within a metallic workpiece and depressions or contours on the workpiece surface. If the cavity is formed as a hollow space within the metallic workpiece, this does not mean a cavity which is closed on all sides, but a cavity which is in contact with the environment of the metallic workpiece at least at one point (eg by means of a bore which connects the cavity to the outer cavity) Surface of the metallic workpiece connects).

An example of a cavity in the sense of the invention is about a cooling or heating channel in a metallic mold. Such metallic molds with integrated heating or cooling channels are used for example in the plastics processing industry for the molding of plastic components. By using such tempered tools on the one hand, an improvement of the component properties (eg surface quality) on the other hand, a reduction of the process times can be achieved. In this case, it is important that the heating or cooling channels integrated into the mold for temperature control be realized with the smallest possible distance from the working surface of the mold so as to avoid unnecessary energy losses and thus an extension of the cycle times. Especially with large-volume molds, the production is characterized by the increasing complexity of the manufactured Components, the resulting complexity of the required heating / cooling channels and the requirement to integrate the heating / cooling channels as close to the surface as possible in the tool as difficult.

The object of the invention is to provide a method which enables a simple and at the same time exact generation of at least one cavity in a metallic workpiece.

This object is achieved by a method having the features of patent claim 1. Advantageous embodiments of the method are realized in the subclaims.

The method according to the invention for producing a metallic workpiece having at least one cavity has the following method steps: a) positioning at least one polymer profile on a substrate; b) at least partially overmolding the at least one polymer profile with metal particles by a thermal spraying method; and c) at least partially triggering the at least one polymer profile after encapsulation. The at least one polymer profile has at least one cavity.

A polymer profile is understood to mean a semifinished product made of a polymeric material. In particular, the polymer profile is profile-shaped, ie with a substantially uniform cross-section and a length which is significantly greater than its width and thickness, formed. Advantageously, the polymer profile consists of a polymeric material which has an elasticity / deformability which allows a manual deformation of the polymer profile. As a result, the position and dimension of the cavity to be generated can be easily adapted.

Under a method for thermal spraying - hereinafter also called thermal spraying or thermal spraying - are understood processes in which the spray material is completely or partially melted and spun in a gas stream in the form of spray particles accelerated onto the surface of the component to be coated, where the particles cool and solidify. The term thermal spraying summarizes various processes which differ in each case by the type of energy carrier used for melting the spray material, by the achievable particle velocity and by the shape of the spray material. The method described for producing a metallic workpiece having at least one cavity can in principle be implemented using all customary injection methods (flame spraying, high-speed flame spraying, plasma spraying, laser spraying, cold gas spraying, detonation spraying, arc spraying). In the following explanations, the method of so-called arc spraying is used as an example. In this method, an arc is ignited between two wires of the desired metallic material, in which the wires are melted. The resulting liquid metal droplets are accelerated by an air flow in the direction of the substrate, where they solidify and thus form a layer of the metallic material.

According to the invention, at least a partial encapsulation of the polymer profile with metal particles by a method for thermal spraying and then at least partial release of the polymer profile. After the release of the polymer profile, a cavity in the workpiece or a depression on the workpiece surface remains. This cavity or depression corresponds to the cavity produced. The position and the dimensions of this cavity can be determined by a corresponding positioning or by appropriate spatial Dimensions of the polymer profile can be adjusted. Thus, an exact and at the same time simple generation of the cavity is possible.

Due to the presence of the cavity in the polymer profile, the triggering is simplified or only made possible with relatively long, narrow cavities. Typically, a triggering medium (e.g., chemical release solvent or heated thermal trigger fluid) is used to initiate. This triggering medium contacts the polymer profile and thus provides triggering. Due to the presence of one or more cavities, the release medium can penetrate faster and further into the polymer profile. There is therefore a more intensive contact between the triggering medium and the polymer profile to be triggered. The time required for triggering is thereby reduced. Also, the volume of material to be triggered is reduced, allowing efficient triggering.

A cavity is understood as meaning regions of the polymer profile which are not filled with the polymeric material constituting the polymer profile but which contain a gaseous component (e.g., air, propellant gas). Examples of such a cavity would be: an internal cavity of a polymer profile designed as a hollow profile, in the case of polymer profiles with a U- or semicircularly curved cross-section of the internal space located within the surrounding material regions or, in the case of foamed polymer profiles, the interior of the foam pores filled with air or propellant gas.

Preferably, the cavity of the polymer profile is designed such that lie in each cross-section of the polymer profile perpendicular to the longitudinal direction of the polymer profile areas of the cavity and area, which are filled with the polymeric material of the polymer profile. To this Ensures uniform release along the entire polymer profile.

In an advantageous embodiment, the polymer profile has a void fraction of at least 10% by volume to at most 90% by volume. Such an area for the void fraction has been found to be advantageous for the triggering. Most preferably, the void fraction is at least 50% by volume. For foamed polymer profiles, the void fraction is preferably at least 50% by volume and at most 99.5% by volume.

Triggering is generally understood as a process step which leads to triggering or detachment of the material of the polymer profile from the cavity. Thus, for example, a chemical decomposition of the polymeric material or heating to a decomposition, a melting and / or softening temperature is possible. If the polymer profile is a foamed polymer profile, the triggering on the one hand can lead to the collapse of the foam and / or to a decomposition of the foam. In an advantageous embodiment, a collapse of the foam takes place during triggering. After the collapse of the foam, a large cavity forms in the cavity. This may then be used to introduce a triggering medium (e.g., chemical release medium or thermal release medium, e.g., heated fluid) such that subsequent chemical decomposition and / or efflux of the collapsed foam residue occurs.

In this case, the triggering can take place both immediately after the cavity has been overmolded and in a subsequent process step, which is separated in time from the encapsulation. Immediately after the cavity has been overmoulded, this means that thermal spraying does not yet have to be completed per se. It just has to be a first layer on that Polymer profile have been applied. After applying this layer, the triggering can usually begin immediately. If the triggering is carried out immediately after the cavity has been encapsulated, the heat produced during the thermal spraying can be used to thermally trigger the polymer profile. If the polymer profile is designed as a foamed profile, then this heat produced during thermal spraying can be used to collapse the foam in a particularly advantageous manner.

In an advantageous embodiment, a further polymer profile is positioned on the metal particles after process step b) or after process step c), and then process step b) is carried out again so that a workpiece is produced with cavities arranged in layers. In this way, a production of layered metallic workpieces is possible. Thus, this embodiment serves as a generative process for the production of workpieces with cavities arranged in layers.

The polymer profile may consist of prefabricated profiles. These can then be positioned in a structurally simple manner on the substrate and then encapsulated.

Advantageously, the step of positioning the at least one polymer profile includes adhering the polymer profile to the substrate. This results in a simple and reliable fixation of the polymer profile on the substrate. An unwanted relative movement between the polymer profile and the substrate can be effectively prevented in this way.

In addition to the use of prefabricated profiles, the polymer profiles can also be produced directly on the substrate. This can by a generation process for directly generating the polymer profile on the substrate. This is advantageously an extrusion process for extruding the polymer composition on the substrate. If the polymer profile is to be made of a foamed polymer profile, it is preferable to carry out a foam extrusion process which produces the foamed polymer profile directly on the substrate.

In an advantageous embodiment, the polymer profile is formed as a foamed polymer profile. In this embodiment, the foam pores thus form the cavity of the polymer profile. The configuration as a foamed polymer profile, a relatively uniform distribution of the void content and the polymer material portion along the longitudinal direction of the polymer profile and along a cross section perpendicular to the longitudinal direction can be achieved. This results in a uniform triggering result over the entire polymer profile. In addition, it comes at the triggering process initially to a collapse of the foam, which can further accelerate the triggering.

In order to ensure a good bonding of the thermally sprayed metal particles to the polymer profiles, the polymer material composing the polymer profiles can be metallized in advance (for example by electroplating). In the simplest case, this metallization can be implemented by wrapping the polymer profiles with a thin metal foil or a thin metal mesh.

In a preferred embodiment, the at least one polymer profile is formed as a hollow profile, in particular as a tubular profile. In this way, the outer contour of the polymer profile can define the dimensions of the cavity. The cavity within the polymer profile, however, contributes to material savings and to improve the triggering.

In a further advantageous embodiment, the outer dimensions of the at least one polymer profile correspond to the dimensions of the cavity to be produced. In this way, the spatial dimensions of the cavity can be defined very precisely.

In a further advantageous embodiment, the at least one polymer profile consists of a chemically soluble polymer material and the triggering takes place with a solvent adapted to the polymer material. In this case, a solvent adapted to the polymer material is understood as meaning a solvent in which the polymer material of the polymer profile dissolves. Since the cavity to be formed communicates with the environment of the metallic workpiece, the solvent can be brought into contact with the polymer profile, whereupon the polymer profile dissolves. The formed cavity remains behind. In a particularly advantageous manner, the solvent is introduced into the cavity of the at least one polymer profile. In this way, a particularly efficient triggering is possible.

In a further advantageous embodiment, the triggering takes place by raising the temperature of the at least one polymer profile to a temperature above a melting range of the polymer material and a subsequent outflow of the molten polymer material. Due to the increase in temperature, the polymer profile melts. The molten polymer can then flow out of the workpiece. The formed cavity remains behind.

In further advantageous embodiments, the increase in the temperature of the at least one polymer profile can also be up to a dissolution or decomposition temperature (temperature at which a decomposition of the polymer material of the polymer profile occurs), a melting temperature (temperature at which it melts the polymer material comes) and / or a collapse temperature (temperature at which collapse of foam bubbles occurs) take place. After reaching the abovementioned temperatures, the polymer profile can then either flow out of the cavity autonomously or be removed from the cavity by introducing a chemical and / or thermal triggering medium.

In general, the triggering can take place until complete removal of the polymer material of the polymer profile. However, it is also possible that the triggering takes place only to a degree that a coating of the polymer material of the polymer profile remains on the metal particles of the cavity. In this way, a coating of polymer material forms on the surface of the cavity produced. This coating in turn can serve, for example, as a wear or corrosion protection layer.

The substrate may consist of a metallic material, in particular of a metallic material in the form of a thermally sprayed layer, a thin sheet or a galvanically deposited layer. By using a metallic substrate, a reliable cohesive connection between the thermally sprayed metal particles and the substrate can be achieved. The connection strength of the entire component is increased in this way.

However, if no cohesive connection between the substrate and the thermally sprayed particles is desired, a non-metallic material, e.g. Ceramic or a temperature-resistant plastic, are used.

Furthermore, to prevent a cohesive connection between the substrate and thermally sprayed particles before the Process step b), in particular before the process step a), a release agent for preventing the cohesive connection of the metal particles are applied to the substrate with the substrate. As a result, a simple separation of the substrate and the generated metallic workpiece is possible.

Advantageously, the substrate has a shape that corresponds to the negative shape of a surface of the workpiece to be produced. As a result, the at least one cavity can be produced particularly close to the surface in the metallic workpiece and any further processing steps that may otherwise be necessary (for example, milling) can be dispensed with.

The substrate may additionally be provided with a support structure. As a result, the metal workpiece can be given the necessary stability. In order to avoid distortion of the workpiece by different thermal expansions, the thermal expansion coefficient of the material of the support structure should be in a similar range as that of the material of the thermally sprayed layer and / or the substrate.

In an advantageous embodiment, the metallic workpiece is designed as a tool mold, the cavity as a heating or cooling channel and the method for thermal spraying as arc spraying. In this way it is possible to introduce one or more heating and / or cooling channels in a tool mold in a simple and cost-effective manner. The molds produced in this way can be used, for example, as molds in the production of, in particular large-volume, components made of carbon fiber reinforced plastic (CFRP).

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated Figures. It is understood that the features mentioned above and the features to be explained below can be used not only in the respectively specified combination but also in other combinations or alone, without departing from the scope of the present invention.

Fig. 1

eine schematische Schnittdarstellung eines Verfahrens zum thermischen Spritzen einer ersten Schicht auf ein Substrat;

Fig. 2

eine schematische Schnittdarstellung des Positionierens von Polymerprofilen auf der thermisch gespritzten Schicht aus Fig. 1;

Fig. 3

eine schematische Draufsicht auf die Polymerprofile aus Fig. 2;

Fig. 4

eine schematische Schnittdarstellung eines Verfahrens zum Umspritzen der in Fig. 2 und Fig. 3 dargestellten Polymerprofile mit Metallpartikeln durch ein Verfahren zum thermischen Spritzen;

Fig. 5

eine schematische Schnittdarstellung des Positionierens von weiteren Polymerprofilen auf der thermischen gespritzten Schicht aus Fig. 4;

Fig. 6

eine schematische Schnittdarstellung eines Auslösens der in Fig. 4 dargestellten Polymerprofile;

Fig. 7

eine schematische Schnittdarstellung eines hergestellten metallischen Werkstücks mit einer Stützstruktur;

Fig. 8

eine schematische Schnittdarstellung eines weiteren metallischen Werkstücks mit schichtartig angeordneten Kavitäten;

Fig. 9

eine schematische Darstellung einer weiteren Draufsicht auf Polymerprofile;

Fig. 10

eine weitere schematische Darstellung einer Draufsicht auf ein Polymerprofil;

Fig. 11a - Fig. 11f

Schnittdarstellungen verschiedener Ausführungsformen von Polymerprofilen mit jeweils mindestens einem Hohlraum; und

Fig. 12a - Fig. 12c

Schnittdarstellungen einer Ausführungsform, in der ein geschäumtes Polymerprofil zunächst umspritzt wird und es beim Auftrag einer weiteren thermisch gespritzten Schicht zu einem Kollabieren des Schaums kommt.

The invention is further explained by means of embodiments and drawings. Show it:

Fig. 1

a schematic sectional view of a method for thermal spraying a first layer on a substrate;

Fig. 2

a schematic sectional view of the positioning of polymer profiles on the thermally sprayed layer Fig. 1 ;

Fig. 3

a schematic plan view of the polymer profiles Fig. 2 ;

Fig. 4

a schematic sectional view of a method for molding the in Fig. 2 and Fig. 3 represented polymer profiles with metal particles by a method for thermal spraying;

Fig. 5

a schematic sectional view of the positioning of other polymer profiles on the thermal sprayed layer Fig. 4 ;

Fig. 6

a schematic sectional view of a trigger of in Fig. 4 represented polymer profiles;

Fig. 7

a schematic sectional view of a manufactured metallic workpiece with a support structure;

Fig. 8

a schematic sectional view of another metal workpiece with layered cavities arranged;

Fig. 9

a schematic representation of another plan view of polymer profiles;

Fig. 10

a further schematic representation of a plan view of a polymer profile;

Fig. 11a - Fig. 11f

Sectional views of various embodiments of polymer profiles, each with at least one cavity; and

Fig. 12a - Fig. 12c

Sectional views of an embodiment in which a foamed polymer profile is first encapsulated and it comes to the application of another thermally sprayed layer to collapse of the foam.

Fig. 1 shows a schematic representation of a method for thermal spraying a first layer on a master mold 1. The original form 1 is in the in Fig. 1 illustrated embodiment designed as a solid component. In the Fig. 1 Upwardly facing surface of the original form 1 has a shape corresponding to the negative shape of a surface of the metallic workpiece to be produced. The prototype 1 can thus be regarded as the negative counterpart to the metallic workpiece to be produced. On the in Fig. 1 upwardly facing surface of the original form 1 2 metal particles 3 are deposited by means of an arc spray gun. In this way, a method for thermal spraying is carried out, which leads to the production of a first thermally sprayed layer 4. The first thermally sprayed layer 4 is used in the in the FIGS. 1 to 7 illustrated embodiment as a substrate and may for example have a thickness of about 1 mm.

Fig. 2 shows a schematic representation of the positioning of polymer profiles 5 on the first thermally sprayed layer 4. This positioning of the polymer profiles 5 is preferably carried out after the first thermally sprayed layer 4 is cooled. The polymer profiles 5 have a semi-annular cross-section and are distributed substantially equidistantly over the first thermally sprayed layer 4. Fig. 3 shows the polymer profiles 5 in a plan view. The attachment of the polymer profiles 5 on the first thermally sprayed layer 4 is carried out by adhering the polymer profiles 5 on the first thermally sprayed layer 4. The polymer profiles 5 are made of a relatively soft, moldable and soluble polymer material. Due to the malleability of the material, the polymer profiles can be easily adapted to the contour of the original form 1.

Fig. 4 shows a schematic representation of a method for overmoulding the in Fig. 2 and Fig. 3 shown polymer profiles 5 with metal particles 3. In this way, the metallic workpiece is further built. The polymer profiles 5 are thus overmolded with metal particles 3 and a second thermally sprayed layer 6 is formed. The final thickness of the metallic workpiece achieved in this way can be, for example, 10 to 20 mm and produced by repeatedly traversing the workpiece with the arc spray gun 2.

Fig. 5 shows a schematic representation of the positioning of other polymer profiles 5 on the thermal sprayed layer Fig. 4 , By reapplying polymer profiles 5, it is possible to construct a multi-layered workpiece, whereby complex geometrical dimensions of the cavities can be realized.

After encapsulation of the polymer profiles 5, the workpiece thus produced can be cooled and then separated from the master mold 1. Maybe it is it is necessary to apply a suitable release agent to the master model 1 before spraying the first thermally sprayed layer 4.

In Fig. 6 the step of detaching the polymer profiles 5 from the workpiece is shown. In this case, the polymer profiles 5 previously overmolded with the metal particles 3 are dissolved with a suitable solvent. Are the profiles used in their cross section tubular - or as in the FIGS. 2 to 7 shown halbbringförmig -, the appropriate solvent can be passed through the cavity of the polymer profiles 5 and thus a rapid dissolution of the polymer material of the polymer profiles 5 can be realized. This process step can also be carried out by using the meltable polymer materials for the polymer profiles 5 by heating the workpiece to a temperature above the melting point of the selected polymer material and thus by melting.

By triggering the polymer profiles 5 from the metallic workpiece, channel-like cavities 7 are produced in the workpiece. These cavities are close to the surface and are only separated from the surface of the workpiece by the first thermally sprayed layer 4. Due to the channel-like cross-section of the cavities produced, these can be used, for example, as heating or cooling channels and thus serve for example for temperature control of the workpiece.

It is also conceivable that the polymer profiles 5 are not completely released from the cavities 7 and thus an inner coating of the channel-like cavities is formed. This is advantageous if, for example, aggressive fluids are to be passed through these channel-like cavities 7.

To increase the stability of the generated metallic workpiece, the workpiece - as in Fig. 7 shown - are provided with a support structure 8.

Fig. 8 shows another metal workpiece with layered arranged polymer profiles 5 unlike in the FIGS. 2 to 6 shown polymer profiles 5 are the polymer profiles 5 in the FIG. 8 not formed semi-annular, but have a square outer cross-section and a square inner cavity, ie the polymer profiles 5 in Fig. 8 are square hollow profiles. The upper part of Fig. 8 shows the prototype 1 with layer-like arranged polymer profiles 5. A first layer of the polymer profiles 5 is partially surrounded by metal particles 3 of the first thermally sprayed layer 4. The second layer of the polymer profiles 5 is partially surrounded by metal particles 3 of the second thermally sprayed layer 6. The polymer profiles 5 of the first layer are glued directly to the surface of the original form 1 here. For these polymer profiles 5, the original form 1 thus represents the substrate and the cavities produced are recesses on the surface of the metallic workpiece to be produced. In this way, the contour of the surface of the metallic workpiece can be determined by the shape of the polymer profiles 5 used and their arrangement. The lower part of Fig. 8 shows the metallic workpiece after the release of the polymer profiles 5, wherein the representation of the metallic workpiece compared to the upper part of the image Fig. 8 rotated 180 °. After the release of the polymer profiles 5 of the first layer, a contour is formed on the surface of the metallic workpiece which corresponds to that of the polymer profiles 5 used. After the release of the polymer profiles 5 of the second layer, channel-like cavities 7 are formed inside the metallic workpiece.

FIGS. 9 and 10 each show alternative arrangements of polymer profiles 5 on the first thermally sprayed layer 4. Similarly to Fig. 3 FIG. 2 shows a plan view of the first thermally sprayed layer 4 with polymer profiles 5 positioned thereon. The FIGS. 9 and 10 are intended to illustrate that the moldability of the polymer profiles 5 and complex courses of the later cavities 7 can be realized.

Another possibility is to apply the polymer profiles 5 in the form of a curable, pasty or foamed mass to the first thermally sprayed layer 4 and to carry out the curing process before the further process steps.

The polymer material of the polymer profiles 5 can be chosen such that it can be dissolved or decomposed with a suitable solvent. By way of example, materials from Belland Technologies GmbH are mentioned here. These materials are soluble in alcohol or alkaline aqueous solutions.

As already shown above, a thermal triggering (melting out) of the polymer profiles 5 is possible. Here, the selected polymer material for the polymer profiles 5 above its melting point should have the lowest possible viscosity. By way of example, polypropylene (PP) is listed here.

in the in Fig. 1 illustrated embodiment, the original form 1 is formed as a solid component. However, it is also conceivable that an adapted in the form of thin sheet represents the original form 1. In this case, it is possible to dispense with the first thermally sprayed layer 4 and, instead, to position the polymer profiles 5 directly on the thin sheet, which later serves as the tool surface. Also the separation of Substrate and produced workpiece would be omitted in this case, since the substrate itself is part of the workpiece produced.

11a to 11f show different polymer profiles 5a, 5b, 5c, 5d, 5e, 5f, each with at least one cavity 9, which are each positioned on the first thermally sprayed layer 4, ie on a substrate. The Figures 11a-11e each show a cross section along the longitudinal direction of the respective polymer profile 5a-5f.

The polymer profile 5a in Fig. 11a is a foamed polymer profile. The individual foam pores are filled with air or propellant gas and each form a cavity 9. The void fraction thus results from the total volume of the foam pores.

The polymer profile 5b in Fig. 11b is a U-shaped polymer profile. The cavity 9 is located within the surrounding material areas. More specifically, the outer material regions of the polymer profile 5b and the upper surface of the first thermally sprayed layer 4 define the cavity 9.

The polymer profile 5c in Fig. 11c is designed as a hollow profile with a rectangular outer cross section and inner cavity 9.

The polymer profile 5d in Fig. 11d is a semi-circular curved polymer profile. The cavity 9 is located within the surrounding material areas. Similar to Fig. 11b Here too, the outer material regions of the polymer profile 5d and the upper side of the first thermally sprayed layer 4 define the cavity 9.

The polymer profile 5e in Fig. 11e is formed as a hollow profile with a round outer cross section and inner cavity 9. It is thus a polymer profile with a tubular cross-section.

The polymer profile 5f in Fig. 11f is formed as a hollow profile with a rectangular outer cross-section and a plurality of internal cavities 9.

FIGS. 12a to 12c show process steps of an embodiment in which a polymer profile 5 designed as a foamed polymer profile 5 collapses (collapses) during thermal spraying. The figures are designed as sectional drawings, wherein the selected sectional plane is selected perpendicular to the longitudinal direction of the polymer profile 5a.

Fig. 12a shows the foamed polymer profile 5a positioned on the first thermally sprayed layer 4. The individual foam pores are filled with air or propellant gas and each form a cavity 9. The foamed polymer profile 5a can either be a prefoamed profile which is already positioned in the foamed state on the first thermally sprayed layer 4 and optionally fixed thereon with an adhesive. However, the foamed polymer profile 5a can also be produced only directly on the first thermally sprayed layer 4 by a foam extrusion process.

In a next process step ( Fig. 12b ), the foamed polymer profile 5a is overmolded by the application of the second thermally sprayed layer 6.

In a further process step ( Fig. 12c ), a further thermally sprayed layer 10 is applied to the second thermally sprayed layer 6. The heat introduced here causes the foamed polymer profile 5a to collapse. The foam residues 11 initially remain in the cavity 7 formed and can subsequently in particular be removed by introducing a thermal or chemical release medium in the resulting cavity 7. The collapse of the foam takes place during the thermal spraying and is triggered by the heat generated by the thermal spraying.

LIST OF REFERENCE NUMBERS

1

prototype

2

Arc spray gun

3

metal particles

4

first thermally sprayed layer

5, 5a, 5b, 5c, 5d, 5e, 5f

polymer profile

6

second thermally sprayed layer

7

cavity

8th

support structure

9

cavity

10

another thermally sprayed layer

11

collapsed foam

Claims (15)

Method for producing a metallic workpiece having at least one cavity (7), the method comprising the following method steps: a) positioning at least one polymer profile (5) on a substrate (1, 4); b) at least partially overmolding the at least one polymer profile (5) with metal particles (3) by a thermal spraying process; c) at least partially triggering the at least one polymer profile (5) after encapsulation; wherein the at least one polymer profile (5) has a cavity (9). The method of claim 1, wherein after the method step b) or c) positioning of a further polymer profile (5) on the metal particles (3) and then the process step b) is carried out again, so that a workpiece with layers arranged cavities (7) is formed , Method according to one of the preceding claims, wherein the positioning of the at least one polymer profile (5) comprises a bonding of the polymer profile (5) to the substrate (1, 4). Method according to one of the preceding claims, wherein the positioning of the at least one polymer profile (5) includes a generation process for directly generating the polymer profile (5) on the substrate (1, 4). The method of claim 4, wherein the generating process includes extruding a polymer mass on the substrate (1, 4). Method according to one of the preceding claims, wherein the polymer profile (5) is formed as a foamed polymer profile (5a). Method according to one of claims 1 to 6, wherein the at least one polymer profile (5) as a hollow profile (5b, 5c, 5e, 5f), in particular as a tubular profile, is formed. Method according to one of the preceding claims, wherein the outer dimensions of the at least one polymer profile (5) correspond to the dimensions of the cavity (7) to be produced. Method according to one of the preceding claims, wherein the at least one polymer profile (5) consists of a chemically soluble polymer material and the triggering takes place with a solvent adapted to the polymer material. A method according to claim 9, wherein the solvent is introduced into the cavity (9) of the at least one polymer profile (5). Method according to one of the preceding claims,
wherein the triggering is carried out by raising the temperature of the at least one polymer profile (5) to a predetermined temperature, in particular above a dissolution temperature, a melting temperature, a decomposition temperature and / or a collapse temperature of the polymer material of the polymer profile and subsequent outflow of the polymer material. Method according to one of the preceding claims, wherein the triggering takes place to a degree that a coating of the polymer material of the polymer profile (5) remains on the metal particles (3) of the cavity (7). Method according to one of the preceding claims, wherein the substrate (1, 4) consists of a metallic material, in particular in the form of a thermally sprayed layer (4), a thin sheet or an electrodeposited layer. Method according to one of the preceding claims, wherein before the process step b), in particular before the process step a), a release agent for preventing the cohesive connection of the metal particles with the substrate (1, 4) is applied to the substrate (1, 4). Method according to one of the preceding claims, wherein the metallic workpiece is designed as a tool mold, the cavity (7) as a heating or cooling channel and the method for thermal spraying as arc spraying.

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