DE102017111846A1 - Process for the production of locally modified molded parts - Google Patents

Abstract

The invention relates to a method for producing locally modified mold parts (10 ') in a casting method using expandable plastics (1), in which by incorporating modifiers (2) composite materials (4) are produced comprising at least the following steps: providing of at least one foaming mold (3) for producing a foaming agent (1 ', 5, 5') added with modifiers (2), filling the foaming mold (3) with at least one expandable plastic (1) and modifiers (2), expanding the plastic (1) and positionally accurate fixing of the modifiers (2) in the foaming product (1 ', 5, 5') and introduction of the foaming agent (1 ', 5, 5') into a casting mold (7), introduction of a liquid metal (14 ') in the mold (7) for producing the mold part (10 '), whereby the expanded plastic (1) evaporates and the modifiers (2) are enclosed by the liquid metal (14') and demoulding the produced mold part (10 ').

Description

The invention relates to a process for the production of locally modified moldings.

Modern cast components are characterized by increasingly high levels of complexity and ever increasing demands. In order to meet the requirements, elaborate technologies are often required during production.

By researching materials that meet the requirements, in particular in the form of so-called composite materials by incorporated carbides or other modifiers particularly high-stress materials are developed. Disadvantage of these materials, however, is that they are often very difficult to process and ver work and that integration of the added modifiers in the basic matrix is extremely complicated, since the particles to be introduced can often be wetted only under vacuum. Furthermore, a homogeneous distribution of these modifiers can not be reliably guaranteed at the current state.

Known from DE 10 2011 012 142 B3 is a casting technology processing of such matrix composite materials or matrix composite, which can be produced by infiltration of prefabricated, mostly ceramic pre-forms by pressure or compression molding, but these procedures are all considered to be complicated and expensive. About it are eg in DE 10 2009 034 969 A1 or DE 69223194 T2 Methods for a powder metallurgy production of a composite material with metal matrix (MMC) described, whereby these methods are to be regarded as extremely complicated and expensive.

Another approach to function fulfillment is based on the fact that the loads occurring on a component are not homogenous, but rather locally differentiated. Manufacturing technology, various approaches are known to overcome these disadvantages, which are assigned to the so-called heterogeneous material concepts. In this case, the differentiated stress or stresses that can occur in a component, are absorbed by a local use of locally required materials. Examples of this are, for example DE 102008036019 A1 or WO 2009/068132 A1 Composite material solutions known, usually realized by an input or encapsulation of geometrically defined reinforcing elements, which may be connected by force, form or material, or thermal coatings, such as in DE 102009024320 B4 mentioned. These solutions are geometrieabhängig very complicated and expensive.

Both a use of composite materials, as well as a production engineering realization of composite materials solutions can be realized by known methods only with the highest technological and associated economic costs.

Against this background, it would be desirable to have a method which overcomes the disadvantages described above.

This object is achieved with a method according to claim 1 and a mold part according to claim 8. Further advantageous embodiments will become apparent from the dependent claims.

• - Bereitstellung von zumindest einer Schäumform (3) zur Herstellung eines mit Modifikatoren (2) versetzten Schäumlings (1', 5, 5'),
• - Befüllung der Schäumform (3) mit zumindest einem expandierbaren Kunststoff (1) und Modifikatoren (2),
• - Expandieren des Kunststoffs (1) und positionsgenaue Fixierung der Modifikatoren (2) im Schäumling (1', 5, 5') und
• - Einbringen des Schäumlings (1', 5, 5') in eine Gießform (7),
• - Einbringen eines flüssigen Metalls (14') in die Gießform (7) zur Erzeugung des Gussformteils (10'), wobei der expandierte Kunststoff (1) verdampft und die Modifikatoren (2) von dem flüssigen Metall (14') umschlossen werden und
• - Entformen des erzeugten, vorzugsweise lokal modifizierten Gussformteils (10').

Proposed is a method for producing locally modified mold parts (10 ') in a casting process using expandable plastics (1), in which by incorporation of modifiers (2) composite materials (4) are produced comprising at least the following steps:

• Providing at least one foaming mold (3) for producing a foaming product mixed with modifiers (2) ( 1' . 5 . 5 ' )
• Filling of the foaming mold ( 3 ) with at least one expandable plastic ( 1 ) and modifiers ( 2 )
• - expanding the plastic ( 1 ) and exact positioning of the modifiers ( 2 ) in the foaming ( 1' . 5 . 5 ' ) and
• - introducing the foaming product ( 1' . 5 . 5 ' ) into a casting mold ( 7 )
• - introducing a liquid metal ( 14 ' ) in the mold ( 7 ) for producing the molded part ( 10 ' ), wherein the expanded plastic ( 1 ) and the modifiers ( 2 ) of the liquid metal ( 14 ' ) and
• Demoulding the produced, preferably locally modified casting ( 10 ' ).

The term composite materials refers both to composite materials and to material composites in the form of compounds.

Under a foaming ( 1' . 5 . 5 ' ), a positive foam model ( 1' ), a reinforcing foam element ( 5 ) and / or a carrier foam or foam insert ( 5 ' ) Understood. A carrier foam or foam insert is understood to mean a geometrically defined and modificated foam element.

Modifiers are understood as meaning particles, fibers, material additives, alloying elements or even reinforcing elements and / or conductor elements

The basic idea of the invention consists in modifying corresponding modifiers, e.g. Particles, preferably carbides, fibers, material additives, alloying elements or even reinforcing elements and / or conductor elements, which are all summarized below as "modifiers", foamed into a foaming. The modifications mentioned can be influencing factors.

The use of these foaming agents ( 1' . 5 . 5 ' ) as a carrier medium for sprues or modifiers has proven to be particularly advantageous for filigree and difficult to position modifiers or sprues.

Upon pouring, the expanded plastic, preferably expanded polystyrene, evaporates, with the modifiers to be introduced removed from the melt, e.g. an aluminum melt, preferably finely divided and are enclosed positionally true. The released EPS gases act as inert protective gases advantageously on the wettability of the modifiers, before they escape, for example, by the unbound quartz sand from a casting mold.

The modifiers can be incorporated into an expanded foam element ( 5 ) are injected. In addition, the modifiers can also be introduced directly into the mold or positioned or injected by means of an injector and / or compressed air and thus positioned.

Foams in the form of particles, eg spheres or foam beads ( 1 ) can be used according to the invention with modifiers ( 2 ), and in this way effecting an entry of these with the advantages described above.

By means of the described invention, modifiers of any type to be introduced can be arbitrarily locally differentiated, but always introduced directly, homogeneously and reproducibly into a cast component directly during the casting process.

The corresponding modifiers can either be converted locally into a foam positive model ( 1' ) to be processed according to the lost foam or a Vollformgießverfahren.

Alternatively, however, it is also possible to use special foams (with the corresponding modifiers) ( 1' . 5 . 5 ' ) are positioned in a mold where the material reinforcement is desired, whereby all known conventional casting methods can be used.

The result of this very economical production is a cast component or cast part (10 ') deliberately reinforced by the modifiers, irrespective of its complexity, which reduces the acting loads by the locally produced composite material (10'). 4 ) is able to accommodate requirements. Thus, it is possible by this manufacturing method to produce targeted locally reinforced components of whatever complexity, which are able to make in the technologically required areas according to the invention specifically structural reinforcements by incorporation of modifiers and the associated production of a composite material.

The production of the composite material ( 4 ) or parts thereof by working the modifiers can by means of a modifier foamed ( 1' . 5 . 5 ' ) in the form of a positive model as one embodiment of the invention to produce the later resulting composite or portions thereof.

When filling the foaming mold ( 3 ) with the expandable plastic, for example, foam beads can be used in unexpanded or partially expanded form. Likewise, modifiers such as carbides, material additives, reinforcing elements, fibers and the like can be used.

When expanding the plastic and the positionally accurate fixation of the modifiers in the foaming, the modifiers can be homogeneously distributed or partially arranged, depending on locally required characteristics in the component or material, in particular with regard to its strength. The introduction of the modifiers of the foaming agent ( 1' . 5 . 5 ' ) into a casting mold ( 7 ) may be accompanied by a positioning of these, but this is not absolutely necessary.

While the expanded plastic evaporates and the modifiers are enclosed by the liquid metal, the modifiers ( 2 ) targeted into the casting material ( 14 ) and thus finely divided in the composite material to be produced ( 4 ) are present. The liberated gases can act as inert shielding gases, such that the wettability of the modifiers is favored.

With the present invention, in one embodiment, a local material engineering or a local component modification using the so-called Vollformprinzips or lost foam principle is provided.

So-called lost (positive) models ( 1' ) made of expandable plastic, preferably polystyrene (EPS), an economical, near-net shape casting. Likewise, by bonding individual EPS layers, complex foam models and cast parts can be produced. According to the invention, the (positive) models ( 1' ) the layers or parts ( 5 ) thereof with modifiers ( 2 ) to the intended composite material ( 4 ) to create.

According to the invention, the process allows with the aid of the so-called lost forms or foaming ( 1' . 5 . 5 ' ) the modifiers ( 2 ) targeted into the cast material ( 14 ) to integrate.

Locally differentiated microstructural influences or modifications can be achieved, for example, by connecting individual partial forms, which may also contain different modifiers, to the final foaming product ( 1' . 5 . 5 ' ) are brought together, whereby cost-effective and easy partial structural reinforcements can be achieved.

In the structurally or technologically highly demanding areas of the component to be produced, the corresponding modifiers can thus be introduced in a targeted and accurate position and in this way components with different mechanical and technical properties in different areas can be generated in a targeted manner.

In a further embodiment of the invention, by foam depositors ( 5 ' ) or the carrier foam ( 5 ' ) enable precise positioning of the modifiers to be introduced in a casting mold in all other known casting methods.

The production and filling of a foaming mold can be carried out as follows:

Depending on the complexity of the cast part to be produced, one or more (part) mold (s) is to be produced in which / a (positive) plastic model or corresponding model parts, i.d.R. Foam models made of expandable polystyrene or styrofoam or polymethyl methacrylate, foamed near net shape / are. Depending on the quantity to be produced, these foaming molds are usually manufactured as permanent metal molds. This corresponds to the common approach of the lost-foam, EPS or full-form process, a lost foam model casting process.

For casting e.g. Of aluminum materials is used as starting material for the production of the models usually with the blowing agent pentane (C5H12) added expandable polystyrene (EPS). For the production of cast iron and steel components, a copolymer of EPS and EPMMA, i. used an expandable polymethylmethacrylate. These two substances are in spherical form and consist of 6% polymer and pentane, the remaining 94% consists of air.

An embodiment of the invention provides that the modifiers ( 2 ) distributed locally or arranged specifically to the foam beads ( 1 ) into the foaming mold ( 3 ) are added and foamed with. In this case, the modifiers can be locally evenly distributed or selectively arranged or accumulated added to the preferably loose foam beads in the foaming mold and foamed with.

Foams or foams can be added or reinforced with modifiers as follows:

When filling the model forms or foam molds ( 3 ) the basic approach of the invention comes into play. Instead of filling the molds homogeneously with the foam particles to be expanded, generally beads, corresponding modifiers are additionally added to the parts of the component which are particularly highly stressed or to be reinforced and locally foamed into the model.

A further embodiment of the invention provides that the modifiers ( 2 ) directly into the foam beads to be foamed ( 1 ) and to a foaming ( 1' . 5 . 5 ' ) or (positive) foam model ( 1' ) are foamed or expanded.

A particularly homogeneous and specific distribution of the added modifiers can thereby be achieved by introducing them into the foam particles which have not yet been expanded

A further embodiment of the invention provides that pre-expanded and modifier-added foam beads are used.

It is also conceivable, however, to introduce the modifiers ( 2 ) into the finished foamed foam model ( 1' ) or parts thereof, eg by infiltration or injection or blowing.

The expansion or foaming can be carried out as follows:

After closing the mold, the preferably locally prepared or mixed with the modifiers foam particles are expanded and generates the corresponding positive model or individual, later to be bonded layers or elements thereof. In general, this is done under the action of temperature in a water bath or by steam (lost foam method).

For example, polystyrene is expandable by the incorporation of pentane as blowing agent (EPS material). By supplying about 110 ° C hot steam, the EPS material is made to expand in a foaming chamber. The resulting overpressure in the free volume between the polystyrene molecules and the softening of the polymer matrix due to the further increase in temperature cause the EPS beads to increase to the desired volume, for example up to about 30 times the original volume.

This procedure achieves the density needed for further processing or the final model needed.

• a) In einer ersten Ausführungsvariante werden die Modifikatoren lose zwischen den Kunststoffperlen (1) bzw. Schaumstoffperlen (1) positioniert oder eingeschüttet und während des Aufschäumens positionsgetreu fixiert.
• b) In einer weiteren Ausführungsform werden die Werkstoff-Modifikatoren, ggf. als EPS- Perlen mit Modifikatoren infiltriert, direkt in die Schäumform und gegebenenfalls lose eingebracht. Sofern lediglich eine lokale Bauteilverstärkung erwünscht ist, geschieht dies in der Art, dass die Modifikatoren sich nur in den gewünschten Bereichen des Schaummodells (1') und somit des späteren Gussbauteils (10') befinden.
• c) Optional ist ein weiterer Zwischenschritt anwendbar, in dem die zuvor lediglich vorgeschäumten EPS-Perlen z.B. mit Druckluft durch einen Injektor in eine Modellform geblasen werden, wo sie zum gewünschten endkonturnahen Positivmodell verschweißt werden. Dies geschieht durch erneutes Bedampfen der Formoberfläche mit ca. 110 °C heißem Wasserdampf, der in den Formhohlraum gelangt oder auf die Form wirkt.
• d.) Durch den erfindungsgemäßen Ansatz, expandierbare Kunststoffe als Trägermedium für die Modifikatoren (2) zu nutzen, ist es möglich, mit oder ohne Vorschäumprozessschritt einzelne, zu verstärkende Bauteilbereich als Verstärkungsschaumelemente bzw. Modellsegmente auszuführen und diese mit dem, die Restgeometrie darstellenden, konventionellen Schaummodell zu verbinden.

The introduction of the material modifiers or modifiers ( 2 ) into the respective foaming mold ( 3 ) can be carried out as follows:

• a) In a first embodiment, the modifiers are loosely placed between the plastic beads ( 1 ) or foam beads ( 1 ) or poured and fixed during the foaming positionally accurate.
• b) In another embodiment, the material modifiers, optionally infiltrated as EPS beads with modifiers are introduced directly into the foam mold and possibly loose. If only a local component reinforcement is desired, this is done in such a way that the modifiers only in the desired areas of the foam model ( 1' ) and thus the later cast component (10 ') are located.
• c) Optionally, a further intermediate step is applicable in which the previously prefoamed EPS beads are blown, for example with compressed air through an injector into a model mold, where they are welded to the desired near-net shape positive model. This is done by re-steaming the mold surface with about 110 ° C hot steam that enters the mold cavity or acts on the mold.
• d.) By the inventive approach, expandable plastics as a carrier medium for the modifiers ( 2 ), it is possible, with or without Vorschäumprozessschritt perform individual, to be reinforced component area as reinforcing foam elements or model segments and to connect them with the remaining geometry representing, conventional foam model.

In connection with the invention described herein, it is also possible in this way to produce two foam substances and to bring targeted use; the homogeneous foam base substance as well as a reinforcing foam mass, in which the modifiers or reinforcing particles were introduced in the process step of pre-foaming and prefoamed accordingly.

By deliberately introducing the optionally previously prefoamed reinforcing foam mass into the homogeneous foam base substance by such an intermediate step, the foam model can be constructed according to requirements in the manner of base and modified foam, that in the later higher loaded component areas introduced in the reinforcing foam modifiers a local material reinforcement in terms of cause local material engineering.

Also, from these different foam substances corresponding portions of the final foam model ( 1' ) finished foamed and then be joined.

In one embodiment of the invention, it is provided that the modifiers ( 2 ) with the foam beads ( 1 ) to separate reinforcing foam elements ( 5 foamed and in discrete areas of the (to be produced) molded part ( 10 ' ) with the residual geometry of the (final) foam model ( 1' ) are joined eg by gluing.

As discrete areas, the particularly stressed areas of a cast component ( 10 ) Understood.

According to a further embodiment of the invention it is provided that the casting ( 1' ) by shaping or pouring out the modifier foamed ( 1' . 5 . 5 ' ) takes place after a Vollformgießverfahren. As a result, for example, a local material optimization is achieved.

The joining and mounting of the model segments:

After foaming and drying of the individual model segments, they can now be assembled to the planned complex model shape. According to method step d), in this way individual model segments in which the desired modifiers are foamed with are connected to the remaining foam model and so on local component gains are generated in a simple manner. This joining is usually done as standard with gluing machines for processing hot glue, which also take over the fixation of the model parts. The joining can also be done by means of any joining method.

To make the overall process more efficient, end models are advantageously connected to a sprue / gating system, creating a so-called model grape. Different models can be attached to this model grape.

Depending on the material used and the desired casting quality, an additional sizing job may be required. For this purpose, the finished model screws are often coated with a water-based, ceramic and gas-permeable sizing. The purpose of this process is to derive the liquid and gaseous components and thus to control the mold filling targeted. In addition, the sizing forms a refractory barrier. The model grapes are then dried to reduce the residual moisture and thus the risk of porosity in the casting. This is usually done in a 50 ° C oven, with microwave drying is possible.

As a subsequent method step, a molding can be performed. When molding, the now dried model grape is placed in a casting container and sprinkled sequentially with a molding material. As a rule, quartz sand is used as molding material, but mullite can also be used.
To model the model or models in detail, the model grape is subjected to vibration, allowing the molding material to flow into all the cavities.

The casting step can be carried out as follows:

Through a runner and a gating system, the molten metal is passed into the foam model, where the thermal energy decomposes or vaporizes the model grape. The melt now completely fills the vacant cavity, whereby after the solidification of the metal, the exact near-net shape part contour is formed.

According to the invention, the previously introduced modifiers are enclosed by the melt.

In the context of the present invention, the gases released upon evaporation of the plastic model may act as inert shielding gases before they escape from the mold through the unbonded molding material or gas-permeable sizing coating. Such an inert protective gas atmosphere can have an advantageous effect on the wettability of the introduced modifiers and thus contribute to a good embedding of the material-enhancing modifiers.

Often, casting the EPS model screws also occurs under a vacuum environment to pull the resulting gases out of the mold. In such an application, a particularly good wetting and embedding of the modifiers is to be expected.

Off eg WO 2013/186124 A1 Moreover, approaches to active cooling of the solidifying metal during the lost foam casting process are known. Such approaches may even further enhance the ultimate strength properties of a component reinforced by the locally incorporated modifiers, but will not adversely affect or oppose them.

A further method step is the emptying of the casting container or of the casting mold ( 7 ), which can proceed as follows:

The emptying takes place for example by tilting the casting container ( 7 ), wherein the molding material, vzw. Quartz sand from the cavities or the cavity ( 15 ) can flow. The quartz sand can then be returned to a sand return system. The removal of possible residues of the size, but also an influence on the mechanical values can be accomplished by a water bath at 30-40 ° C.

As a result of a manufacturing application of this invention, even the most complex castings with requirement-oriented, locally differentiated material properties can be produced in an economically advantageous manner, as well as in 8th shown.

According to the invention, by means of this method, the casting ( 10 ' ) also by inserting the with modifiers ( 2 ) offset foaming ( 1' . 5 . 5 ' ) into a cavity ( 15 ) and filling the cavity ( 15 ) with liquid metal ( 14 ') be generated. Also this procedure leads to a local material optimization, as well as in 6 shown.

In addition, the invention is also conceivable using other casting methods. In this sense, the foaming agents added with the desired modifiers could also be used as depositors in conventional casting processes, as well as in 5 shown.

In this way, individual component areas to be reinforced can also be optimally optimized with the aid of the introduced modifiers. Possibly. would be in such an application, additional degassing or targeted suction required to reduce gases in the component and thus the risk of porosity, since the mold is formed in this case, not from loose, but rather from bonded molding material or permanent metal molds, as well as in 6 shown.

As an example of application for this, connecting elements and / or reinforcing elements and / or conductor elements could be introduced into specific component regions by the use of geometrically defined, preferably cylindrical, foams set with modifiers. Furthermore, these modified foaming agents could also be used to image treads of pistons of any type in a tri-logical and mechanical manner in an advantageous manner, as a result of which costly coating processes can be completely substituted, for example 7 shown.

Proposed is a locally modified molded part ( 10 ' ) produced in a casting method described above using expandable plastics ( 1 ), by introducing modifiers ( 2 ) Composites are produced.

Such components which can be produced by the process according to the invention and fields of application for this are regarded as follows:

With the full-forming process or lost-foam process, complex components can be produced today, as they can not be produced in any other casting process. The advantages of the method make it possible to easily implement complicated geometries. Examples can be found in aerospace engineering, medical technology, the automotive industry, but also in many other areas where classical casting processes, such as die casting or die casting, are reaching their limits.

By means of the described invention, material composites but also composite materials in the form of metal matrix composites (MMCs) can be produced economically and reliably using this method. These composite materials can also be arranged locally in a component according to its requirement profile.

In addition, according to the invention, foams mixed with the desired modifiers can also be used as depositors in conventional casting processes.

By introducing the modifiers close to the surface into a model or casting, complex surface coatings can also be completely substituted.

The method according to the invention is diversified in respect of its applicability. For example, a use of the method in the field of automotive engineering, especially for internal combustion engines, brake discs, electric motors conceivable.

Following the approach, expensive coatings, e.g. thermal coating, with e.g. wear-resistant or tribologically advantageous coating materials are completely replaced by the property-promoting elements (particles or the like) in the form of foamed modifiers described here are introduced near the surface directly into the plastic model. As an example of application, modifier-added cylindrical foams could reinforce component regions in which fasteners are to be introduced.

In addition, these foaming agents added with modifiers could also image treads of pistons of any type in a triological and mechanical manner in an advantageous manner, as a result of which, for example, costly coating processes can be completely substituted.

• Es zeigen:
  • 1: schematisch eine mit Schaumstoffperlen (1) und Modifikatoren (2) versehene Schäumform (3) zur Herstellung von lokal modifizierten Gussformteilen (10'),
  • 2 und 3: schematisch weitere Schäumformen (3), die mit Schaumstoffperlen (1) und Modifikatoren (2) versehen sind,
  • 4: schematisch ein (Positiv-) Schaumstoffmodell (1') mit eingebrachtem Verstärkungsschaumstoffelement (5),
  • 5: ein Gussbauteil (10') das in dem durch ein Belastungselement (6) hochbeanspruchten Bauteilbereich durch eine lokale Werkstoffoptimierung/Verbundwerkstoff (4) verstärkt wird,
  • 6: schematisch eine Gießform (7) mit eingelegtem Schäumling (5'),
  • 7: schematisch ein Gussformteil (10') mit lokal durch Modifikatoren erzeugtem Verbundwerkstoff (4) und
  • 8: schematisch ein zu einer Gießtraube gefügtes (Positiv-) Schaummodell (1'), das in verschiedenen Bereichen durch unterschiedliche eingebrachte Modifikatoren (11, 12, 13) präpariert ist, so dass im zu erzeugenden Gussbauteilteil anforderungsgerecht unterschiedliche Gussgefüge bzw. Verbundwerkstoffe entstehen

The invention is explained below with reference to figures, the invention not being limited thereto:

• Show it:
  • 1 : schematically one with foam beads ( 1 ) and modifiers ( 2 ) provided foaming mold ( 3 ) for the production of locally modified molded parts ( 10 ' )
  • 2 and 3 : schematically further foam forms ( 3 ) with foam beads ( 1 ) and modifiers ( 2 ),
  • 4 : schematically a (positive) foam model ( 1' ) with incorporated reinforcing foam element ( 5 )
  • 5 : a cast component ( 10 ' ) in which by a loading element ( 6 ) highly stressed component area by a local material optimization / composite material ( 4 ),
  • 6 FIG. 1 schematically shows a casting mold (FIG. 7 ) with foamed egg ( 5 ' )
  • 7 FIG. 2: schematically a casting ( 10 ' ) with locally produced by modifiers composite material ( 4 ) and
  • 8th FIG. 1: schematically a (positive) foam model joined to a casting grape ( 1 '), which has been introduced in different areas by different modifiers ( 11 . 12 . 13 ), so that different cast structures or composite materials are produced in the casting component part to be produced in accordance with requirements

In 1 is schematically one with foam beads ( 1 ) and modifiers ( 2 ) provided foaming mold ( 3 ) for the production of locally modified molded parts ( 1 ').

• - Bereitstellung von zumindest einer Schäumform (3) zur Herstellung eines mit Modifikatoren (2) versetzten Schäumlings (1', 5, 5'),
• - Befüllung der Schäumform (3) mit zumindest einem expandierbaren Kunststoff (1) und Modifikatoren (2),
• - Expandieren des Kunststoffs (1) und positionsgenaue Fixierung der Modifikatoren (2) im Schäumling (1', 5, 5') und
• - Einbringen des Schäumlings (1', 5, 5') in eine Gießform (7),
• - Einbringen eines flüssigen Metalls (14') in die Gießform (7) zur Erzeugung des Gussformteils (10'), wobei der expandierte Kunststoff (1) verdampft und die Modifikatoren (2) von dem flüssigen Metall (14') umschlossen werden und
• - Entformen des erzeugten Gussformteils (10').

The process for producing these locally modified moldings ( 10 ' ) in a casting process using expandable plastics ( 1 ), by introducing modifiers ( 2 ) Composite materials ( 4 ), comprises at least the following steps:

• - providing at least one foaming mold ( 3 ) for producing a with modifiers ( 2 ) offset foaming ( 1' . 5 . 5 ' )
• Filling of the foaming mold ( 3 ) with at least one expandable plastic ( 1 ) and modifiers ( 2 )
• - expanding the plastic ( 1 ) and exact positioning of the modifiers ( 2 ) in the foaming ( 1' . 5 . 5 ' ) and
• - introducing the foaming product ( 1' . 5 . 5 ' ) into a casting mold ( 7 )
• - introducing a liquid metal ( 14 ' ) in the mold ( 7 ) for producing the molded part ( 10 ' ), wherein the expanded plastic ( 1 ) and the modifiers ( 2 ) of the liquid metal ( 14 ' ) and
• Demoulding the produced casting ( 10 ' ).

The modifiers ( 2 ) can be distributed locally or arranged selectively to the foam beads ( 1 ) into the foaming mold ( 3 ) are added and foamed with.

Out 2 is schematically another foaming mold ( 3 ) recognizable with foam beads ( 1 ) and modifiers ( 2 ), the modifiers ( 2 ) directly into the foam beads to be foamed ( 1 ) and to a foaming ( 1' . 5 . 5 ' ) or foam model ( 1' ) are foamed.

3 schematically shows another foaming mold ( 3 ) with foam beads ( 1 ) and modifiers ( 2 ), with pre-expanded and with modifiers ( 2 ) offset foam beads ( 1 ) are used.

In 4 is schematically a foam model ( 1' ) with a reinforcing foam element ( 5 ), the modifiers ( 2 ) with the foam beads ( 1 ) to a separate reinforcing foam element ( 5 ) foamed and at the desired or discrete areas of the casting ( 10 ' ) with the residual geometry of the final foam model ( 1' ).

5 shows a finished component or casting ( 10 ' ) with a locally produced or to be produced material modification or composite material ( 4 ), whereby by a loading element ( 6 ) generated demands can be recorded according to the requirements.

6 FIG. 1 schematically shows a casting mold (FIG. 7 ), with a runner with a gating system ( 8th ) and a sprue ( 8th' ), as well as a schematically indicated molten metal or a liquid cast material ( 14 ' ), which can be filled in the run. In the mold ( 7 ) is a foaming agent mixed with modifiers ( 1' . 5 . 5 ' ) whose expandable foam beads ( 1 ) during the molten metal inlet ( 14 ' ), whereby the modifiers to be introduced are enclosed and absorbed finely distributed by the inflowing melt. The liberated gases can be exhausted or degassed ( 9 ) are passed out of the cavity to prevent possible porosities in the cast component.

According to the method, the production of the casting ( 10 ' ) by inserting the with modifiers ( 2 ) offset foaming ( 5 ' ) into a cavity ( 15 ) and filling the cavity with liquid metal ( 14 ' ). This procedure also leads to local material optimization.

7 FIG. 2: schematically a casting ( 10 ' ) with a locally modified material or composite material ( 4 ) in or on a cast material ( 14 ) is arranged. The casting ( 10 ' ) can be used for example in a locally reinforced cylinder head or crankcase application.

Out 8th schematically another mold, consisting of molding sand ( 7 ' ), wherein the later casting ( 10 ' ) by shaping it with modifiers ( 2 ) offset foam model ( 1' ) can be done after a Vollformgießverfahren. The supply of molten metal ( 14 ' ) takes place via a sprue ( 8th' ) and casting with gate system ( 8th ) in the foam model ( 1' ).

In accordance with requirements, modifiers of different types, for example type A ( 11 ) and / or type B ( 12 ) and / or type C ( 13 ) are introduced locally.

Thus, according to the procedure according to the invention using expandable plastics ( 1 ) as a carrier medium for the modifiers ( 2 ) purposefully composite materials ( 4 ) and thus locally modified moldings ( 10 ' ) getting produced.

LIST OF REFERENCE NUMBERS

(1')

Positive foam model or foam model

(1)

Foam bead (expandable)

(2)

modifier

(3)

foaming

(4)

modified material or composite material

(5)

Reinforcing material element

(5 ')

Carrier foam or foam insert

(6)

loading element

(7)

mold

(7 ')

molding sand

(8th)

Casting and gating system

(8th')

sprue

(9)

Exhaust / degassing

(10 ')

Mold part

(10)

Highly loaded area in the casting (10 ')

(11)

locally introduced modifiers (e.g., type A)

(12)

locally introduced modifiers (e.g., type B)

(13)

locally introduced modifiers (e.g., type C)

(14)

Cast material

(14 ')

Molten metal / liquid casting material

(15)

cavity

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 102011012142 B3 [0004]
• DE 102009034969 A1 [0004]
• DE 69223194 T2 [0004]
• DE 102008036019 A1 [0005]
• WO 2009/068132 A1 [0005]
• DE 102009024320 B4 [0005]
• WO 2013/186124 A1 [0063]

Claims (8)

Method for producing locally modified mold parts (10 ') in a casting method using expandable plastics (1), in which composite materials (4) are produced by introducing modifiers (2), comprising at least the following steps: Providing at least one foaming mold (3) for producing a foaming agent (1 ', 5, 5') offset with modifiers (2), Filling the foaming mold (3) with at least one expandable plastic (1) and modifiers (2), - Expanding of the plastic (1) and positionally accurate fixation of the modifiers (2) in the foaming (1 ', 5, 5') and - introducing the foaming material (1 ', 5, 5') into a casting mold (7), - Introducing a liquid metal (14 ') in the mold (7) for producing the mold part (10'), whereby the expanded plastic (1) evaporates and the modifiers (2) are enclosed by the liquid metal (14 ') and - Mold removal of the produced molded part (10 '). Method according to Claim 1 , wherein the modifiers (2) distributed locally or selectively arranged to the foam beads (1) are added to the foam mold (3) and foamed with. Method according to Claim 1 , wherein the modifiers (2) are integrated directly into the foam beads (1) to be foamed up and foamed into a foamed product (1 ', 5, 5') or foam model (1 '). Method according to Claim 1 , where pre-expanded and with modifiers (2) offset foam beads (1) are used. Method according to one of the preceding claims, wherein the modifiers (2) are foamed with the foam beads (1) into separate reinforcing foam elements (5) and joined to discrete areas of the casting part (10 ') with the residual geometry of the foam model (1'). Method according to one of the preceding claims, wherein the casting mold part (10 ') takes place by molding or pouring out the foaming agent (1', 5, 5 ') added with modifiers (2) by a full casting process. Method according to one of the preceding claims, wherein the casting mold part (10 ') is introduced into a cavity (15) by inserting the foaming agent (1', 5, 5 ') mixed with modifiers (2) and filling the cavity (15) with liquid metal ( 14 ') is generated. Locally modified molded part (10 ') produced in a casting method according to one of the preceding claims, using expandable plastics (1) in which composite materials (4) can be produced by introducing modifiers (2).

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