DE102016216916A1 - Mold, in particular hollow mold for a gravity die casting process and method for producing a casting mold - Google Patents

Abstract

In order to provide a casting mold, in particular a hollow casting mold for a gravity die casting process, with which the production of hollow cast structures with wall thicknesses of less than 5 mm is reliably ensured, in a casting mold (100), in particular a hollow casting mold for a gravity die casting process, with at least a cavity (10) for producing at least one hollow cast structure (26) comprising a casting tool (12) and a core (14), the at least one cavity (10) being spaced from a surface (13) of the core (14) and from a cavity (10) Casting surface (11) of the casting tool (12) is limited, wherein the at least one cavity (10) defining casting surface (11) of the casting tool (12) at least in a partial area (15) has a surface structuring (16), proposed that the at least one cavity (10) limiting surface (13) of the core (14) at least in a partial area (17) aufwei a surface structuring (18) st.

Description

The invention relates to a casting mold, in particular a hollow casting mold for a gravity die casting process, having at least one cavity for producing at least one hollow casting structure comprising a casting tool and a core, wherein the at least one cavity is delimited by a surface of the core and by a casting surface of the casting tool, wherein the casting surface defining the at least one cavity of the casting tool has a surface structuring at least in a partial region. Furthermore, the present invention relates to a method for producing a casting mold, in particular a hollow casting mold for a gravity die casting process.

State of the art

Production restrictions locally increase the minimum wall thickness of castings produced in series production of lightweight aluminum alloy vehicle parts. The structurally required strength of the castings is significantly increased by the process-related required additional amount of material. Reason for the restrictions is a limitation of the flow length of the molten aluminum, which results from the surface tension of the melt and on the melt front forming oxide skin. Due to these restrictions, currently castings, in particular hollow cast structures, can only be realized with wall thicknesses of more than 5 mm.

From the DE 10 2014 221 852 A1 the applicant is a casting tool having at least one cavity for producing at least one casting known, in which a cavity defining the casting surface of the casting tool at least partially having a surface structuring. By providing a surface structuring on the casting surface of the casting tool, an increase in the flow length of the molten metal can be achieved, so that castings produced can also have smaller wall thicknesses of less than 5 mm.

From the DE 10 2008 028 197 A1 is a piston for an internal combustion engine, known with a piston skirt and a cast piston head with a piston crown, a land, a ring section and a piston head in the amount of the ring section cooling channel, wherein the surface of the cooling channel has circumferential grooves.

Hollow-cast structures can be made in gravity die casting using so-called lost cores. The material used for the cores is sand, or salt cores can be used. However, surface structuring known from the prior art can not at present be used in the casting of hollow casting structures. Thin-walled hollow cast structures that are to be produced in gravity die casting and whose wall thicknesses are less than 5 mm are currently not feasible under high-volume conditions.

Presentation of the invention, object, solution, advantages

The invention has for its object to provide a mold, in particular a hollow mold for a gravity die casting process, with which the production of hollow cast structures with wall thicknesses of less than 5 mm is reliably possible. A further object of the present invention is to provide a method for producing such a casting mold.

According to the invention, this object is achieved by providing a casting mold, in particular a hollow casting mold for a gravity die casting method, wherein the casting mold has at least one cavity for producing at least one hollow casting structure and comprises a casting tool and a core, wherein the at least one cavity extends from a surface of the core and is delimited by a casting surface of the casting tool, wherein the casting surface of the casting tool delimiting the at least one cavity has a surface structuring at least in a partial region and in which it is provided that the surface of the core delimiting the at least one cavity has a surface structuring at least in a partial region.

By using structured tool surfaces or a surface structuring of a portion of a surface of a core and a portion of a casting surface of a casting mold hollow cast structures with wall thicknesses of less than 5 mm can be produced under high-production conditions under gravity conditions in gravity gravity casting. The production of thin-walled hollow cast structures in the gravity die casting method is made possible according to the invention in that both a partial region of the casting surface of the casting tool and a partial region of the surface of the core are provided with a surface structuring. In other words, it is achieved in an advantageous manner that production restrictions no longer locally increase the minimum wall thickness of the cast parts. The cast parts only have the structural minimum wall thickness required, and a harmony of process and structure-mechanical design of castings is achieved.

The provided with a surface structuring portions of the surface of the core and the casting surface of the casting tool are used in the gravity die casting of, for example, aluminum also support the mold filling.

Advantageously, by providing a surface structuring of at least a portion of the surface of the core and a surface structuring of at least a portion of the casting surface of the casting a specific roughness of the at least one cavity limiting surface of the core and the casting surface of the casting tool obtained. This roughness minimizes the area of contact between the molten metal and the casting surface of the casting tool as well as the surface of the core. The local flow rate of the molten metal is increased by the surface structuring based on local turbulent flows. In addition, the simultaneous surface structuring of the surface of the core and the casting surface of the casting tool promotes rupture of the oxide skin forming on the molten metal. Furthermore, due to a wetting behavior influenced by the surface structuring, an air layer or an air cushion is advantageously produced between the molten metal and the surface of the core or casting surface of the casting tool, which has an insulating effect. The air layer prevents the thermal energy of the molten metal from being reduced by the direct contact with the surface structuring of the casting tool. Thus, the molten metal flows further than in known molds, in particular hollow molds, in which the molten metal has direct contact with an unstructured casting surface or an unstructured surface of a core.

Compared with the solutions known in the prior art, by simultaneously providing a surface structuring of at least a portion of the surface of the core and a surface structuring of at least a portion of the casting surface of the casting tool, the flow length of the molten metal at the same wall thickness of the casting increased or the wall thickness of the casting can at the same flow length be reduced. Of course, a combination of increasing the flow length and reducing the wall thickness is possible. Due to these advantages, thin-walled hollow cast structures with wall thicknesses of less than 5 mm can be safely produced in terms of process engineering.

The surface structuring of the surface of the core may also cover the entire surface of the core. The surface structuring of the casting surface of the casting tool may also cover the entire casting surface of the casting tool.

It is preferably provided that the core is a lost core. Furthermore, it is preferably provided that the core has a salt and / or a salt-like material, wherein the core preferably consists of salt and / or of a salt-like material.

For the gravity die casting of thin-walled hollow cast structures are preferably salt cores. The know-how in the production of gravity cast components can be transferred to the production of the salt cores or the cores, which have a salt or a salt-like material or which preferably consist of salt or of a salt-like material.

Alternatively, the core may also comprise sand or a sand-like material or consist of sand or a sand-like material. For the production of sand cores, however, a complex sand core production and sand preparation is necessary. Furthermore, resulting from the low thermal conductivity of the sand used high cycle times in the production of hollow cast structures. Therefore, a core comprising a salt or a salt-like material or a core consisting of salt or of a salt-like material is preferably provided. Furthermore, it is advantageous that by forming the core of a salt or a salt-like material for the production of hollow cast structures no sand treatment plants must be purchased. Compared to the sand core, the core manufacturing process eliminates the need for a core having a salt or a salt-like material or consisting of a salt or a salt-like material, so that the salt core production can take place on site and at low cost.

It can preferably be provided that the surface structuring of the subregion of the surface of the core and / or the surface structuring of the subregion of the casting surface of the casting tool is a directional structuring, in particular a structuring oriented in a direction of flow of a molten metal in the cavity, and / or an unoriented structuring.

A directed structuring advantageously has at least one elevation or depression which extends in the direction of flow of a molten metal in the at least one cavity. Directed structures are particularly suitable to be used on portions of the surface of the core or the casting surface of the casting tool, on which a preferably fast and highly directed flow of the molten metal is to be expected. The in flow direction Aligned structures hinder the transverse movement of the vortices in the turbulent flow on the surface of the core and / or the casting surface of the casting tool. With particular advantage, the wall friction can be reduced by about 10% or more in this way. This reduction in resistance results in an increase in the flow length of the molten metal of approximately 50% or more.

Non-oriented structures may have elevations or depressions, which are in particular symmetrical and have no preferred direction with regard to their arrangement. Such structurings are particularly suitable for flow areas in the cavity in which a slow, and with respect to the direction undefined flow of the molten metal is to be expected. The non-directional surface structuring reduces the contact area between the molten metal and the casting surface or the surface of the core and increases the flow length and the flow velocity or flow velocity of the molten metal.

For example, directional structures may consist of furrows, grooves, or ridges oriented substantially in a same direction. However, other preferential structures also fall within the definition of directed structuring.

Advantageously, a more effective and less error-prone filling of the cavity can be achieved by means of the directional and / or the non-directional structuring of the surface of the core or of the casting surface of the casting tool. Thus, defects such as bubbles or voids in the hollow structure can be avoided. As a result, in particular, the amount of rejects in Hohlgussschraftraftkokillengießverfahren is reduced.

Further, it is preferably provided that the surface structuring of the partial region of the surface of the core and / or the surface structuring of the partial region of the casting surface of the casting tool is formed, the flow direction and / or the flow velocity and / or the surface tension and / or an oxide layer of a molten metal in the cavity to influence and / or to influence the heat exchange and / or the friction behavior between the portion of the surface of the core and / or the portion of the casting surface of the casting tool and a molten metal in the cavity.

Advantageously, by influencing, in particular increasing the flow rate, a greater flow length of the molten metal in the cavity can be achieved, which is delimited by the surface of the core and the casting surface of the casting tool. Due to the increased flow length, material thicknesses of hollow cast structures of less than 5 mm can be achieved. Also by the change of the friction behavior, in particular by a reduction of the effective friction coefficient, a higher and thus advantageous flow length is achieved. Furthermore, the heat exchange between the partial region of the surface of the core and / or the partial region of the casting surface of the casting tool and a molten metal in the cavity can advantageously be influenced. In particular, a reduction in the heat flow between the molten metal and the surface of the core or the casting surface of the casting tool can be achieved. Thus, less heat flows from the molten metal into the cavity-defining surface of the core and into the casting surface of the casting tool, so that the molten metal has a lower viscosity over a longer period of time, whereby the flow length of the molten metal is increased. Optionally, it may also be advantageously possible to influence the flow direction of the molten metal in the cavity. Such an influence can specifically influence the local flow behavior of the molten metal, so that a more effective and faster filling of the cavity is achieved. As a result, cycle times can be reduced.

The surface structuring of the partial area of the surface of the core and / or the surface structuring of the partial area of the casting surface of the casting tool are preferably a bionic structure, in particular a shark skin structure and / or a crow-foot-like structure and / or a bamboo structure and / or a symmetrical structure and / or an asymmetric structure.

As possible surface structuring for the surface of the core and / or the casting surface of the casting tool, for example, in the DE 10 2014 221 852 A1 the applicant can be used.

Bionic structures are structures that are derived from nature and use the advantages associated with them. It is known that a shark skin structure reduces frictional resistance. The same applies to crow-foot-like structures or bamboo structures. Bionic structures are often also designed as directed structures with which the advantages of directed structures can be obtained. The structures may be symmetrical or asymmetrical. A symmetrical structure may, for example, have a discrete or continuous rotational symmetry about a symmetry axis of the structure. Furthermore, a symmetric structure also be translationally symmetric. These include, in particular, bamboo structures.

It is preferably provided that the surface structuring of the subregion of the surface of the core and / or the surface structuring of the subregion of the casting surface of the casting tool have or have different structures.

With particular advantage directed and / or non-directional and / or symmetric and / or asymmetric and / or bionic structures may also be provided together, that is, different structural types for the surface structuring of the surface of the core and / or for the surface structuring of the casting surface of the casting tool be used. In the case of a common use of these structures, for example, a partial area of the surface of the core and / or a partial area of the casting surface of the casting tool may have different bionic structures with different configurations and different orientations. Furthermore, a combination of very different directional and / or non-directional and / or symmetrical and / or asymmetric and / or bionic structures can be arranged on the same subregion of the surface of the core and / or the casting surface of the casting tool. Through targeted use of the different structural types, the flow direction and / or the flow rate, the heat exchange and / or the friction behavior of the molten metal in the cavity can be locally influenced. This leads to an advantageous reduction of the cycle times and a particularly efficient and process-reliable filling of the cavities for producing a hollow cast structure.

Particularly preferably, it can be provided that the core can be produced, preferably produced, by a casting method, in particular by a chill casting method, preferably a gravity die casting method, and / or by the die casting method and / or a low-pressure casting method, and / or that the core is produced by a pressing method can be produced, preferably produced, is.

By manufacturing the core in a casting process, know-how in the manufacture of gravity cast components can be transferred to the manufacture of the core. The casting of the core has the advantages of easy structuring and high design freedom. Casting or structuring of the cores can be done using existing resources at the site.

By making the cores in a casting process, they can be made by casting into permanent molds. This achieves an efficient and rapid production of the cores, which is also process-reliable, so that the rejection of defective cores is reduced.

Preferably, it is further provided that the surface structuring of the subregion of the surface of the core can be produced, preferably produced, by the casting process and / or by the pressing process, wherein a core molding tool which can be used or used to produce the core comprises a die having a shaping surface which acts as a negative the surface structuring of the portion of the surface of the core is formed.

Shaping surfaces of core molds usable to make the core may be patterned by known methods, such as a laser-shade process. Advantageously, by using a core mold having a die having a forming surface, particularly in conjunction with a casting process, the surface structuring of the at least a portion of the surface of the core is made directly during the casting process of the core, particularly the core of salt or salt core. The cores provided with the surface structuring by the casting process can be treated as in the prior art known cores and placed in the casting tool.

Although additively manufactured sand cores can be used in principle, the production of these cores is expensive because their manufacturing process is too slow. Micro-milled structured salt cores can also be provided in principle. However, their production is also expensive. In addition, the production of a core with a surface structuring of a portion of the surface of the core in a casting process is cheaper and easier because the necessary know-how from the production of gravity cast components can be transferred to the production of cores, especially the salt cores.

Preferably, it can further be provided that the surface structuring of the partial area of the surface of the core and / or of the partial area of the casting surface of the casting tool and / or the shaping surface of the core molding tool by a laser method and / or a cutting process and / or a milling process, in particular a micro-milling , and / or a compression molding method and / or an embossing method can be produced, preferably produced.

In particular, it can be provided with preference that the surface structuring of the partial area of the surface of the core produced in a casting process is carried out using a laser method and / or or a machining process and / or a milling process and / or a compression molding process and / or an embossing process. However, the use of a laser process and / or a cutting process and / or a milling process and / or a compression molding process and / or an embossing process is particularly advantageous for the preparation of the surface structuring of the portion of the casting surface of the casting tool and / or for the production of the forming surface of the core mold.

Such methods, in particular laser methods such as, for example, a laser color method, are particularly flexible and it is possible to produce a wide variety of surface structures for the partial area of the casting surface of the casting tool or the shaping surface of the core molding tool at short cycle times. By structuring the shaping surface of the core forming tool by means of one of the methods mentioned, the surface structuring of the subregion of the surface of the core which results after the casting of the core can likewise be made particularly flexible and versatile. By selecting, aligning and extent of the surface structuring of the surface of the core and / or the casting surface of the casting tool in particular local properties such as flow length, flow direction or flow rate of the molten metal in the cavity can be optimized. Thus, the cycle times for the production of hollow cast structures can be reduced particularly advantageously. In particular, the common surface structuring of the casting surface of the casting tool and the surface of the core, the mold filling is effectively supported so that casting defects are avoided. Advantageously, thin-walled hollow cast structures can be produced effectively and reliably.

• – Bestimmung der Geometrie des Kerns,
• – Fertigung eines Kernformwerkzeugs,
• – Strukturierung einer formgebenden Fläche des Kernformwerkzeuges, wobei die Strukturierung als Negativ einer herzustellenden Oberflächenstrukturierung mindestens eines Teilbereichs der Oberfläche des Kerns ausgebildet ist,
• – Abguss einer Salzlösung in das Kernformwerkzeug, zur Herstellung des Kerns umfassend die Oberflächenstrukturierung mindestens eines Teilbereichs der Oberfläche des Kerns,
• – Aushärtung und Entnahme des Kerns aus dem Kernformwerkzeug,

sowie die Schritte

• – Bestimmung der Geometrie des Gießwerkzeugs,
• – Fertigung des Gießwerkzeugs,
• – Strukturierung mindestens eines Teilbereichs der Gießfläche des Gießwerkzeugs,
• – Einlegen des Kerns in das Gießwerkzeug zur Herstellung mindestens eines Hohlraums, wobei der mindestens eine Hohlraum von einer Oberfläche des Kerns und von einer Gießfläche des Gießwerkzeugs begrenzt wird.

A further solution to the problem underlying the invention is provided by providing a method of making a previously described mold comprising the steps

• - determination of the geometry of the core,
• - manufacture of a core mold,
• Structuring a shaping surface of the core forming tool, wherein the structuring is formed as a negative of a surface structuring of at least a partial region of the surface of the core to be produced,
• Casting a saline solution into the core mold, to produce the core comprising the surface structuring of at least a portion of the surface of the core,
• Hardening and removal of the core from the core mold,

as well as the steps

• Determination of the geometry of the casting tool,
• - production of the casting tool,
• Structuring at least a portion of the casting surface of the casting tool,
• - Inserting the core into the casting tool for producing at least one cavity, wherein the at least one cavity is delimited by a surface of the core and by a casting surface of the casting tool.

With the method according to the invention, the above-described advantages of the casting mold can be achieved with the casting mold obtainable according to the method.

By casting the core by casting a salt solution into the core mold, a particularly fast, efficient and process-reliable production of the core, in particular of the salt core, with a surface structuring is made possible.

The core geometry is advantageously determined by the cavity, which is needed for the production of the hollow cast structure.

Preferably, it may be provided that before the structuring of the shaping surface the core mold and / or before the structuring of a portion of the casting surface of the casting tool computer-aided simulations, preferably with tracer representation, and / or model-based simulations to determine the flow direction of a molten metal in the cavity of Mold are performed, wherein results of the simulation are used to determine the produced surface structuring of the subregion of the surface of the core and / or the surface structuring of the subregion of the casting surface of the casting mold.

By using the results of the simulations, the size and / or the number of partial regions or the size of the surface or of the surface structures provided with the surface of the core or the casting surface of the casting tool can be determined. It can also be determined whether directional and / or non-directional structures should be provided. When applying or structuring the shaping surface of the core forming tool, it is preferable to ensure that the structures there must be recessed in order to be raised on the core to be produced by means of the core forming tool. When structuring the partial region of the casting surface of the casting tool, it is preferable to ensure that the structures must be raised there.

After inserting the core into the casting tool, a casting process, in particular a gravity die casting process with a melt, in particular a molten metal, such as an aluminum melt, can be carried out in order to obtain a hollow cast structure.

As a result of the patterning of at least one partial area of the casting surface of the casting tool and at least one partial area of the surface of the core, the mold filling for the casting process of the hollow casting structure is effectively supported so that casting defects are avoided. Thus, thin-walled hollow cast structures with wall thicknesses of less than 5 mm can be produced.

The computer-assisted simulations are preferably carried out at the beginning of the method or before the structuring of a shaping surface of the core molding tool and / or before the structuring of at least one subregion of the casting surface of the casting tool. The results of the computer-aided simulations can then be validated in model-based simulations, in particular casting experiments on models.

The simulations for the intended finished casting mold are preferably carried out and thus designed for the product or the casting. However, it can also be provided that partial simulations in computer-aided or model-supported execution are carried out separately for the core or the casting tool. If the results of the simulations are used to determine the surface structuring to be made of the subregion of the surface of the core, it should be noted that the surface structuring of the subregion of the surface of the core determined by the results obtained must first be applied in negative mold to the shaping surface of the core molding tool. so that after the salt solution has been poured into the core mold, a core with a surface structuring of a partial area of the surface of the core is available, with which the results of the simulation are implemented.

However, the results of the simulations can also be applied directly to the manufactured core, as far as it is further processed in a post-processing process.

A tracer is a simulated metal melt particle. Through the representation of tracers via the computer-aided simulation or the simulation tool, the movement of the melt can be easily understood. As a result, the orientation of the surface structures of the surface of the core and of the casting surface of the casting tool to be introduced, in particular directed or non-oriented, can be better defined.

Further preferably, it can be provided that the structuring of the partial area of the casting surface of the casting tool and / or the structuring of the shaping surface of the core molding tool by a laser method and / or a cutting process and / or a milling process, in particular a micro-milling process, and / or a pressure molding process and / or a stamping process takes place.

It can further be provided that the surface structuring of the subregion of the surface of the core after the removal from the core molding tool is finished with a laser method and / or a cutting method and / or a milling method, in particular a micromilling method, and / or a compression molding method and / or an embossing method becomes.

By post-processing of the surface structuring of the subregion of the surface of the core after removal from the core mold, minor modifications to the surface structuring may be made, which are necessary for the hollow cast structure, for example by changing process parameters for the hollow casting process.

In addition, where appropriate, casting defects in the production of the core can be compensated.

Brief description of the figures

An embodiment of the invention will be explained below with reference to the drawings. Show it:

1 a schematic representation of a portion of a mold with a casting tool and a core,

2 an example of a bionic structure,

3 a hollow cast structure,

4 a core for producing a hollow cast structure,

5 a laser grain plant for producing a core mold,

6 a perspective view of a hollow cast structure,

7 an example of undirected structuring, and

8th an example of a waffle pattern structure.

Detailed description of the figures

1 shows a schematic representation of a portion of a mold 100 , in particular a hollow mold for a gravity die casting process. The mold 100 has a cavity 10 for producing at least one hollow casting structure, not shown. The cavity 10 is from a casting area 11 a casting tool 12 and a surface 13 a core 14 limited. In a subarea 15 the casting surface 11 of the casting tool 12 is a surface structuring 16 arranged. The core 14 also has a subarea 17 the surface 13 a surface structuring 18 on. Furthermore, in 1 represented as a molten metal 19 in the cavity 10 the mold 100 flows. At the frontline 20 the molten metal 19 an oxide layer forms 21 , which together with a surface tension of the molten metal 19 the flow rate and thus the flow length of the molten metal 19 in the cavity 10 reduced or limited.

2 shows a plan view of a surface structuring 16 . 18 , which are located at one of the two subareas 15 . 17 or at both subareas 15 . 17 the casting surface 11 of the casting tool 12 or the surface 13 of the core 14 can be arranged. The surface structuring 16 . 18 points in the 2 illustrated case surveys 22 on which a bionic structure 23 exhibit. The illustrated bionic structure 23 is also called sharkskin structure 24 designated. The sharkskin structure 24 is aligned in a preferred direction A, so it is a directional structuring 25 ,

Returning to 1 can the surface structuring 16 . 18 only in one subarea 15 . 17 the casting surface 11 of the casting tool 12 or the surface 13 of the core 14 be formed or arranged. However, it is also possible that the surface structuring 16 . 18 the entire casting area 11 of the casting tool 12 or the entire surface 13 of the core 14 which the cavity 10 limit, cover. Furthermore, simultaneous to the directional structuring 25 in the form of the sharkskin structure 24 out 2 Further structuring such as crow-foot-like structures, bamboo structures, symmetrical structures, asymmetric structures, directional and non-directional structuring for surface structuring 16 . 18 of the casting tool 12 or the core 14 be provided.

3 shows a hollow cast structure 26 , which in the form of Hohlgussradträgers 27 is trained. The surface 28 of Hohlgussradträgers 27 is either completely or partially as a structured surface 29 educated. For the production of the structured surface 29 in a gravity die casting process, the in 4 illustrated core 14 in a casting tool 12 used. The core 14 is as a so-called lost core 30 formed and made of salt. Thus the Hohlgussradträger 27 from the 3 by the gravity die casting method the structured surface 29 gets, is the surface 13 of the core 14 in the form of a negative mold with a surface structuring 18 such as in 2 provided provided.

5 shows a schematic representation of a Lasernarbanlage 31 , The laser grain plant 31 has a laser 32 on. Lasernarbung can be a core mold 33 , which in the laser grain plant 31 is arranged, with a shaping surface 34 be provided. The shaping surface 34 has a negative form 35 the surface structuring 18 of the subarea 17 the surface 13 of the core 14 on. After completion of the core mold 33 is by casting a saline solution in the core mold 33 a core 14 produced, which at least in a partial area 17 the surface 13 of the core 14 a surface structuring 18 having.

By inserting the core thus prepared 14 in the casting tool 12 becomes the mold 100 provided for a gravity chill casting process. With the mold thus provided 100 can in the gravity die casting a hollow cast structure 26 such as a Hohlgussradträger 27 getting produced.

6 shows a cross section along the line AA through the Hohlgussradträger 27 in 3 , The Hohlgussradträger 27 has an inner cavity 36 on, which in the hollow casting process by the provided at the appropriate point core 14 in the mold 100 will be produced. By using the mold 100 can the Hohlgussradträger 27 have a wall thickness D, which 5 mm or less. This corresponds to a reduction of the wall thickness D by 20% to 35% compared to known hollow cast structures. This reduction is achieved by simultaneous use of a surface structuring 18 at least one subarea 17 the surface 13 a core 14 and a surface structuring 16 at least one subarea 15 the casting surface 11 a casting tool 12 allows.

Alternative to surface structuring 16 . 18 in the form of a sharkskin structure 24 can also the in 7 undirected structuring 37 with pimples 38 be provided. Such an undirected structuring 37 is particularly suitable for areas with a slow and non-directional flow of a molten metal 19 in the cavity 10 the mold 100 , Basically, so-called waffle patterns 39 , as in 8th can be used, which consist of at right angles to each other standing ridges 40 are formed.

LIST OF REFERENCE NUMBERS

100

 mold

10

 cavity

11

 casting surface

12

 casting tool

13

 surface

14

 core

15

 subregion

16

 surface structuring

17

 subregion

18

 surface structuring

19

 molten metal

20

 front

21

 oxide

22

 survey

23

 Bionic structure

24

 Sharkskin structure

25

 Directed structuring

26

 Hollow-cast structure

27

 Hohlgussradträger

28

 surface

29

 Structured surface

30

 Lost core

31

 Lasernarbanlage

32

 laser

33

 Core mold

34

 Shaping surface

35

 negative form

36

 cavity

37

 Undirected structuring

38

 burl

39

 waffle

40

 ridge

A

 preferred direction

D

 Wall thickness

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• DE 102014221852 A1 [0003, 0024]
• DE 102008028197 A1 [0004]

Claims (10)

Casting mold ( 100 ), in particular hollow casting mold for a gravity die casting process, with at least one cavity ( 10 ) for producing at least one hollow cast structure ( 26 ) comprising a casting tool ( 12 ) and a core ( 14 ), wherein the at least one cavity ( 10 ) from a surface ( 13 ) of the core ( 14 ) and from a casting surface ( 11 ) of the casting tool ( 12 ), wherein the at least one cavity ( 10 ) limiting casting area ( 11 ) of the casting tool ( 12 ) at least in a subarea ( 15 ) a surface structuring ( 16 ), characterized in that the at least one cavity ( 10 ) limiting surface ( 13 ) of the core ( 14 ) at least in a subarea ( 17 ) a surface structuring ( 18 ) having. Casting mold ( 100 ) according to claim 1, characterized in that the core ( 14 ) has a salt and / or a salt-like material, wherein the core ( 14 ) preferably consists of salt and / or of a salt-like material. Casting mold ( 100 ) according to claim 1 or 2, characterized in that the surface structuring ( 18 ) of the subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ) and / or the surface structuring ( 16 ) of the subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ) a directed structuring ( 25 ), in particular one in a flow direction of a molten metal ( 19 ) in the cavity ( 10 ) oriented structuring, and / or an undirected structuring ( 37 ). Casting mold ( 100 ) according to one of the preceding claims, characterized in that the surface structuring ( 18 ) of the subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ) and / or the surface structuring ( 16 ) of the subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ), the flow direction and / or the flow velocity and / or the surface tension and / or an oxide layer of a molten metal ( 19 ) in the cavity ( 10 ) and / or the heat exchange and / or the friction behavior between the subregion ( 17 ) of the surface ( 13 ) of the core ( 14 ) and / or the subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ) and a molten metal ( 19 ) in the cavity ( 10 ) to influence. Casting mold ( 100 ) according to one of the preceding claims, characterized in that the surface structuring ( 18 ) of the subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ) and / or the surface structuring ( 16 ) of the subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ) a bionic structure ( 23 ), in particular a sharkskin structure ( 24 ) and / or a crowsfoot-like structure and / or a bamboo structure and / or a symmetrical structure and / or an asymmetric structure. Casting mold ( 100 ) according to one of the preceding claims, characterized in that the core ( 14 ) by a casting method, in particular by a chill casting method, preferably a gravity die casting method, and / or by a die casting method and / or a low-pressure casting method, can be produced, preferably produced, and / or that the core ( 14 ) can be produced by a pressing process, preferably produced, is. Casting mold ( 100 ) according to claim 6, characterized in that the surface structuring ( 18 ) of the subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ) can be produced, preferably produced, by the casting method and / or by the pressing method, wherein one for producing the core ( 14 ) usable or used core mold ( 33 ) a die having a shaping surface ( 34 ), which as a negative surface structuring ( 18 ) of the subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ) is trained. Method for producing a casting mold ( 100 ) according to one of the preceding claims, comprising the steps - determining the geometry of the core ( 14 ), - manufacture of a core mold ( 33 ), - structuring of a shaping surface ( 34 ) of the core mold ( 33 ), wherein the structuring as a negative of a surface structuring ( 18 ) at least one subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ), casting a saline solution into the core mold ( 33 ), for the production of the core ( 14 ) comprising the surface structuring ( 18 ) at least one subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ), - hardening and removal of the core ( 14 ) from the core mold ( 33 ), as well as the steps - determination of the geometry of the casting tool ( 12 ), - production of the casting tool ( 12 ), - structuring of at least one subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ), - inserting the core ( 14 ) in the casting tool ( 12 ) for producing at least one cavity ( 10 ), wherein the at least one cavity ( 10 ) from a surface ( 13 ) of the core ( 14 ) and from a casting surface ( 11 ) of the casting tool ( 12 ) is limited. A method according to claim 8, characterized in that prior to the structuring of the shaping surface ( 34 ) of the core mold ( 33 ) and / or before the structuring of a subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ) Computer-aided simulations, preferably with a tracer representation, and / or model-based simulations for determining the flow direction of a molten metal ( 19 ) in the cavity ( 10 ) of the mold ( 100 ) are carried out, whereby for the determination of the surface structuring ( 18 ) of the subarea ( 17 ) of the surface ( 13 ) of the core ( 14 ) and / or surface structuring ( 16 ) of the subarea ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ) Results of the simulations are used. Method according to claim 8 or 9, characterized in that the structuring of the subregion ( 15 ) of the casting surface ( 11 ) of the casting tool ( 12 ) and / or the structuring of the shaping surface ( 34 ) of the core mold ( 33 ) by a laser method and / or a cutting method and / or a milling method, in particular a micro-milling method, and / or a compression molding method and / or an embossing method.

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