DE102019207553A1 - Manufacturing process with additive manufacturing of a shaped body, manufacture of a mold and heat treatment - Google Patents

Abstract

A method for producing a component (10) is specified which comprises a) the additive production of a molded body (11) for the component (10), in particular from a powder bed (P), b) the formation of risers (12) and / or feeders (13) on the molded body (11), c), the production of a mold (30) around the molded body (11), the mold (30) being designed for the molded body (11) to keep a remelting or recrystallization process dimensionally stable, d), heat treatment (T) of the molded body (11) for the component (10) in the mold (30) so that a structural change is at least partially effected, and e), the removal of the Shape (30). A correspondingly manufactured component and a computer program product are also specified.

Description

The present invention relates to a method for producing a component, comprising the additive production of a molded body for the component and the production of a shape around the molded body, as well as a subsequent heat treatment.

The component is preferably intended for use in a turbomachine, preferably in the hot gas path of a gas turbine. The component preferably consists of a superalloy, in particular a nickel- or cobalt-based superalloy. The alloy can be precipitation hardened, solid solution hardened, oxide dispersion hardened or hardenable accordingly.

Modern gas turbines are subject to constant improvement in order to increase their efficiency. However, this leads, among other things, to ever higher temperatures in the hot gas path. The metallic materials for rotor blades, especially in the first stages, are constantly being improved with regard to their strength at high temperatures (creep load, thermomechanical fatigue).

Due to its shaping potential, generative or additive manufacturing is also becoming increasingly interesting for the series production of the above-mentioned turbine components, such as turbine blades or burner components.

Additive manufacturing processes include, for example, as powder bed processes (English: PBF "powder-bed-fusion"), selective laser melting (SLM) or laser sintering (SLS), or electron beam melting (EBM). Further additive processes are, for example, “Directed Energy Deposition (DED)” processes, in particular laser deposition welding, electron beam or plasma powder welding, wire welding, metallic powder injection molding, so-called “sheet lamination” processes, or thermal spray processes (VPS LPPS, GDCS).

A method for selective laser melting is known from, for example EP 2 601 006 B1 .

Additive manufacturing processes (AM: “additive manufacturing”) have also proven to be particularly advantageous for complex or filigree components, for example extensive labyrinth-like structures or cooling structures. In particular, additive manufacturing is advantageous due to a particularly short chain of process steps, since a manufacturing or manufacturing step of a component can largely take place on the basis of a corresponding CAD file and the selection of corresponding manufacturing parameters.

Metallic components that are manufactured using AM technologies inherently display a microstructure which, in terms of its structure and composition, is similar or similar to a material produced by welding. The rapid solidification of the metal during remelting in powder bed-based processes results in materials whose properties are essentially dominated by the speed of solidification. Depending, for example, on the scanning or scanning speed and the beam diameter, temperature gradients of 10 ⁵ K / s or even 10 ⁶ K / s or more can occur. The structures, structures and phases generated in this way are far removed from those of a corresponding chemical-physical state of equilibrium. This results in numerous anisotropies and inhomogeneities in the chemical or crystalline properties and mechanical technical parameters. Comparisons show that the material properties of additively manufactured components sometimes lag far behind the properties of components manufactured using casting technology, which is a decisive disadvantage or a decisive limitation of the use of AM components. Along with the described disadvantageous properties, the problem of susceptibility to hot cracks known from welding technology occurs for some materials, which is also caused by the high thermal gradients during the AM process.

In order to solve the problems mentioned, attempts are already being made to improve the material properties of the components by means of (thermal) post-treatments. The properties or characteristic values mentioned can include, for example, the yield strength, the tensile strength, the elongation at break, the impact energy, the hardness, the strength or other aspects.

With post-heat treatments, structures or structures, such as grain sizes and precipitations, can be created, influenced and / or optimized. In this way, improvements can also be achieved, for example in the creep strength and the fatigue strength. These thermal aftertreatments essentially utilize the ability of the respective material to change its properties through diffusion processes in such a way that its structure or properties approach the respective states of equilibrium. However, the possibilities of these thermal processes end at the latest when the lowest eutectic temperature or solidus temperature of the respective material, in particular the phase or composition in question, is reached. When this temperature is reached or exceeded, the solid material is irreversibly damaged and / or by local melting loses its shape. In practice, this limit is already reached at approx. 80% of the respective melting temperature, for example in the case of steels, since in this area many materials have reduced their strength to such an extent that their dimensional stability is lost.

From an economic point of view, weld-like structures cannot be built up without exceeding the solidus temperature. The reason for this limitation is that the diffusion paths and diffusion times necessary for achieving and equilibrium are too long for an economical or efficient manufacturing process. For this reason, components produced with additive technologies hardly achieve the technically required mechanical and / or structural parameters.

According to the state of the art, many highly stressed components are therefore produced by casting. The properties of components produced by casting are more favorable compared to components produced by welding, because the chemical composition that occurs during the solidification of the cast is closer to the respective state of equilibrium of the corresponding alloy or phase.

There is therefore a need to combine the shaping advantages or degrees of design freedom of additive manufacturing or manufacturing technology with the more favorable material properties of casting technology, for example investment casting.

It is therefore an object of the present invention to provide means which solve the objects or problems described.

This object is achieved by the subject matter of the independent patent claims. Advantageous refinements are the subject of the dependent claims.

One aspect of the present invention relates to a method for producing a component, comprising the additive production of a shaped body or a preform for the component, preferably by means of, but not limited to, powder bed-based methods (PBF) such as selective laser melting, selective laser sintering or electron beam melting .

The method further comprises the formation of risers and / or feeders in or on the molded body.

The term “riser” is preferably understood to mean a vent, or a corresponding space or cavity in which the material of the molded body or the component - for example during subsequent remelting or heat treatment - can expand or in which it can rise.

The term “feeder” is preferably understood to mean a material depot from which material for the molded body or component can be provided - for example during subsequent remelting or heat treatment - in order to prevent defects or pores from occurring as a result of shrinkage processes.

In one embodiment, the method comprises the formation of risers or at least one riser.

In one embodiment, the method comprises the formation of feeders or at least one feeder.

The method further comprises the production of a mold or a molded shell around the molded body, the mold being designed to keep the molded body dimensionally stable for a remelting or recrystallization process or a corresponding heat treatment. In the case of a remelting process, the shell mold must have a design that is suitable for shaping a liquid phase. In other cases, a training that ensures dimensional stability during, for example, subsequent heat treatment is sufficient. In addition, the mold can be provided with cooling plates and insulation in accordance with the state of the art.

In one embodiment, the mold is produced or provided in a manner similar to known casting or molding processes, in particular the lost wax process. As a result, the shell mold can be applied to the molded body or encased it in a single operation or in several operations. The shape can still be a green shape.

In one embodiment, the molded body or the mold is fired or appropriately heat-treated during or after its manufacture. This firing or a heat treatment for this purpose should be clearly differentiated in the present case from a subsequent heat treatment which affects the shaped body.

The method further comprises the heat treatment of the molded body for the component in the mold, so that at least partially a structural change, in particular a recrystallization of the material of the molded body, a diffusion of certain structural components and / or a chemical or stoichiometric change is brought about.

In the case of an elementary metallic shaped body or a shaped body that does not consist of an alloy, this can be both simply remelted and only locally melted for the described structural change. In the case of local melting, a further heat treatment (see below) can be applied after the heat treatment described above, in particular after the production of the component, in order to heal any structural defects and / or porosity again.

If the shaped body is made from an alloy, only local or local melting can destroy the structure (“incipient melting” describes grain boundary melting). This phenomenon cannot be remedied, for example, with a renewed heat treatment and / or hot isostatic pressing. In the event that a melting temperature of the material of the molded body is exceeded during the heat treatment, it may be necessary for cavities provided in the design of the component or molded body to be filled with a suitable material, for example a core, in order to keep these cavities free.

The structural transformation allows the material properties of additively manufactured structures to be advantageously matched to cast-like structures. The properties mentioned are preferably matched to those of a thermodynamic or statistical equilibrium of the material of the shaped body.

Although the purely additive manufacturing process with the present invention is complicated by the manufacture of the mold, there are nevertheless decisive advantages for the method described and for the component to be manufactured with it.

At the same time, however, the described invention can decisively improve the material properties for components manufactured by means of AM and, in particular, emulate the advantageous properties of a cast structure. These improved or more favorable material or structural properties expediently allow a much higher load capacity, for example thermal and / or mechanical loading during operation of the component and the prevention of crack formation or propagation, structural defects and material creep. In total, the advantages of both manufacturing approaches can be implemented by the present invention.

The method further comprises the subsequent removal of the mold and, if necessary, the removal of existing cores or core-like agents (see above). The removal can advantageously take place by mechanical smashing or chemical leaching or etching. Accordingly, the shape can be a lost shape. Along with the removal of the mold, for example, corresponding means for forming the risers or feeders can also be removed.

In one embodiment, the component is already completed by the steps described.

In an alternative embodiment, the production of the component requires further steps, for example post-treatment steps, in order to complete it.

In one embodiment, the shape is defined by the outer surfaces of the molded body.

In one embodiment, the heat treatment of the shaped body takes place at a temperature which is greater than a eutectic temperature or a, in particular, lowest, solidus temperature of the material of the shaped body. According to this embodiment of the method, as described, preferably precisely the required structural changes, in particular including remelting and / or recrystallization processes, can be provoked or carried out. As indicated above, the involvement of a complete liquid melt is not necessarily required. Therefore, the method does not necessarily require reaching a melting temperature of the material of the shaped body, but - for example in the case of pure metals - only the eutectic temperature or solidus temperature.

A person skilled in the art knows that exceeding the solidus temperature does not necessarily lead to complete melting of the component, but merely to a loss of its strength or dimensional stability, for example.

In one embodiment, a position of the risers and / or feeders and the shaped body is selected such that essentially no pores or cavities form during the heat treatment of the shaped body and / or any impurities or slag are displaced during the melting process, in particular into a riser. By means of suitable measures, as are known in the prior art of casting, the present invention can also produce single-crystal or directionally solidified structures. Accordingly, the component structure obtained by the present invention can be similar or identical to a structure obtained by a casting process, in particular a monocrystalline, directionally solidified or columnar crystalline structure. For example, these structures can be analogous to the so-called “Bridgeman process” and or with the help of the formation of a single-crystal solidification front and Appropriate germ depots and grain selectors are produced.

In one embodiment, a design and / or a position of the risers or feeders on the molded body is calculated, simulated or optimized. This can be achieved, for example, using a corresponding computer program or computer program product or an algorithm contained therein or a corresponding simulation calculation. Without appropriate computer program means or a corresponding computing capacity, an arrangement and design of the risers or feeders depending on the component geometry can possibly be too complex. The mentioned design of the risers and feeders (see above) can preferably mean their size, nature, composition and / or shape.

A computer program product such as a computer program means, for example, as a storage medium, e.g. Memory card, USB stick, CD-ROM, DVD, or also in the form of a downloadable file from a server in a network are provided or included. This can be done, for example, in a wireless communication network by transmitting a corresponding file with the computer program product or the computer program means.

In one embodiment, a material or starting material for the molded body is selected in such a way that chemical and / or metallurgical material changes that occur during the heat treatment are taken into account or compensated for with regard to a target structure of the component, for example in advance. The choice of the material for the shaped body can also be made in a computer-implemented manner by means of a correspondingly calculated or simulated alloy or composition.

In one embodiment, the molded body is made from a first material.

In one embodiment, the shaped body is made up of a steel or a refractory metal or an alloy comprising at least one of these materials. Alternatively, the material of the shaped body can comprise another metal or another metallic alloy.

In one embodiment, the molded body, in particular its surface, is specifically provided with, preferably only a single nucleating agent and / or a lack of nucleating agents during additive manufacturing from the first material, in order, for example, during the heat treatment to selectively or predeterminedly a nucleus for the formation of a specific crystal - or to provide grain structure for the component or to suppress a crystallization or nucleation for grain growth accordingly. This can be done, for example, by physical or chemical conditioning, coating, structuring or processing of the component surface.

In one embodiment, the heat-treated shaped body is post-treated, for example by a further heat treatment and / or hot isostatic pressing. This post-treatment can be necessary in order to finish the component with sufficient structural quality, for example by curing cracks, defects or stresses in this way.

In one embodiment, the additive manufacturing or construction of the molded body takes place by means of selective laser melting. Alternatively, the manufacture or construction can be carried out by means of electron beam melting or other additive processes.

In one embodiment, at least the production and removal of the mold are carried out analogously to a casting process, in particular an investment casting or lost wax process.

Another aspect of the present invention relates to a component which can be or can be produced by means of the method described. The component further comprises a cast-like microstructure, for example a columnar, columnar crystalline, directionally solidified or monocrystalline microstructure or crystal structure or a polycrystalline microstructure that is essentially free of pores and voids. As indicated above, this crystal or microstructure is more like, similar or corresponds to a thermodynamic or chemical state of equilibrium than would be the case for the structure of the additively constructed molded body without heat treatment.

In one embodiment, the component is intended for use in the hot gas path of a gas turbine.

Another aspect of the present invention relates to a computer program product, comprising instructions which, when the program is executed by a computer, cause the computer to perform the steps of selecting, simulating and / or providing the molded body during additive manufacturing with nucleating agents or a lack of nucleating agents perform.

Refinements, features and / or advantages which in the present case relate to the method for producing the component can also Component itself or relate to the computer program product or vice versa.

As used herein, the term "and / or" when used in a series of two or more items means that any of the listed items can be used alone, or any combination of two or more of the listed items can be used.

• 1 deutet eine schematische Schnittansicht einer additiven Herstellungsanlage an;
• 2 zeigt ein vereinfachtes Flussdiagramm, welches Verfahrensschritte der vorliegenden Erfindung andeutet;
• 3 deutet beispielhaft einen additiv hergestellten oder herstellbaren Formkörper an;
• 4 deutet an, dass der Formkörper mit einer Form versehen wird;
• 5 deutet eine Wärmebehandlung des Formkörpers an;
• 6 deutet das Entfernen der Form an;
• 7 zeigt beispielhaft eine konkrete Ausgestaltung des Formkörpers bzw. Bauteils, sowie Einzelheiten des beschriebenen Verfahrens;
• 8 zeigt eine zu der 7 alternative Ansicht.

Further details of the invention are described below with reference to the figures.

• 1 indicates a schematic sectional view of an additive manufacturing plant;
• 2 shows a simplified flow diagram which indicates method steps of the present invention;
• 3 indicates, by way of example, a molded body produced or produced additively;
• 4th indicates that the molded body is being provided with a shape;
• 5 indicates a heat treatment of the shaped body;
• 6th indicates the removal of the form;
• 7th shows an example of a specific configuration of the molded body or component, as well as details of the method described;
• 8th shows one to the 7th alternative view.

In the exemplary embodiments and figures, elements that are the same or have the same effect can each be provided with the same reference symbols. The elements shown and their proportions to one another are fundamentally not to be regarded as true to scale; rather, individual elements can be shown exaggeratedly thick or with large dimensions for better illustration and / or for better understanding. Accordingly, the functional details disclosed here are not to be understood as restrictive, but merely as an illustrative basis that offers the person skilled in the art in this technical field instructions for using the present invention in a wide variety of ways.

1 shows an additive manufacturing facility 100 . The attachment 100 is preferably a conventional system for the construction or manufacture of parts or components using the powder bed process (PBF). These methods include, for example, selective laser sintering, selective laser melting or electron beam melting. The techniques mentioned make use of a powder bed made from a powder or base material, which is selectively applied in layers with an energy beam 51 , for example a laser beam, is applied, melted and then solidified. A corresponding beam source 50 can for example be provided by an electron source or a laser. The first layer of the component or body to be built up becomes, as soon as it is energized, with a substrate plate 1 connected ("welded"). The further layers are also materially bonded to the respective underlying layers and built up according to a predetermined geometry, which is specified, for example, by a CAD file.

A molded body within the meaning of the present invention can, as described in more detail below, via the production plant 100 can be produced or provided additively. Alternatively, the shaped body can be built up using other, non-powder-bed-based processes, for example “Directed Energy Deposition (DED)” processes, in particular laser deposition welding. Further possibilities for the production of the shaped body are electron beam or plasma powder welding, wire welding, metallic powder injection molding, so-called “sheet lamination” process, or thermal spraying process (VPS LPPS, GDCS).

After the irradiation of each layer, the substrate plate 1 preferably lowered by an amount corresponding to the layer thickness L so that a new layer can be applied. This takes place, for example, by means of a coating device 60 . A production surface H is accordingly preferably always at the same vertical level of the system 100 . The production surface H can be formed, for example, by fresh powder P or also by areas of the component that have already partially melted 10 .

The component is preferably a component which is used in the hot gas path of a turbo machine, for example a gas turbine. In particular, the component can be a rotor or guide vane, a segment or ring segment, a burner part or a burner tip, a frame, a shield, a heat shield, a nozzle, seal, a filter, a mouth or lance, a resonator, punch or a swirler designate, or a corresponding transition, insert, or a corresponding retrofit part.

2 indicates method steps of the present invention on the basis of the schematic flow diagram. The method relates to a method for producing a component such as that described above.

The method comprises, a) the additive manufacturing of a molded body 11 (as described above) for the component 10 from a powder bed P.

The method further comprises, b), the formation of enhancers 12 and / or feeders 13 in or on the molding 11 .

The method further comprises, c), producing a mold 30th around the molded body 11 around, taking the shape 30th is formed, the molded body 11 to keep its shape stable for a remelting or recrystallization process.

The method further comprises, d), the heat treatment of the shaped body 11 for the component 10 in the shape 30th so that a structural change is at least partially effected. The heat treatment is preferably carried out at a temperature T.

The method further comprises e) removing the mold 30th , for example by mechanical smashing, compare 6th below.

The method can comprise further method steps, for example finishing steps, such as, f), an after-treatment or further heat treatment of the molded body which has already been heat-treated 11 and / or hot isostatic pressing. After or in the course of completion, the described method can also include quality assurance or quality control and, for example, be optically measured. In particular, a non-destructive material test, metallographic analysis, hardness measurement and a determination of the mechanical-technical parameters of the component can be determined, evaluated and used to optimize the method.

The present invention also relates to a computer program or computer program product (see reference symbol CPP in 2 ), which is set up in particular, at least some of the in 2 to execute described method steps completely or partially by computer program means. In particular, the additive manufacturing of the shaped body can be used 11 , preferably the geometry and irradiation strategy of the shaped body, and the formation of the risers and / or feeders or a corresponding arrangement of these elements in or on the shaped body 11 be carried out using the computer program (computer program product).

Based on 3 to 8th the presented method as well as a component obtained, manufactured or manufacturable thereby is described in detail. Parts of the described process sequence can be designed similarly or analogously to a conventional investment casting process, for example a lost wax process.

3 shows in particular a shaped body constructed, for example, as described above 11 . The molded body has a cavity, a cavity or a channel 20th on. For example, the shaped body can denote a fluid-cooled or correspondingly coolable by means of a fluid turbine blade.

The shaped body also has an outer surface 14th on.

The shaped body can also be used only as an example 11 can be specifically provided with a nucleating agent or nucleus K during its additive production, for example in order to remelt it during a subsequent heat treatment for the purpose of adjusting the structure, or to change the structure of the molding (cf. 4th below) to provide or to provoke a crystallization or a grain growth corresponding to a certain phase and / or orientation. A subsequent heat treatment can also be used to heal any defects.

The shaped body can also 11 already built up during additive manufacturing in such a way that, for example, there is a lack of nuclei or nucleation agents and a customary or expected crystallization, crystal orientation and / or phase is suppressed.

In 3 is also shown by way of example that - analogously to the Bridgeman method - a spiral grain or single crystal selector GS already in the course of the additive production of the shaped body 11 can be provided. It is to be expected that with the additive construction of a structure, a polycrystalline structure is initially formed, the grains or crystal orientations of which can then be sorted out, at least for the most part, preferably via the grain selector GS. The grain selector GS is structurally preferably connected to the actual molded body via a “reducing section” 11 connected. On the molded body 11 The side of the grain selector GS facing away from the above-described nucleus K is indicated by way of example, which is preferably used to form a single or columnar crystalline structure of the component.

A position of a nucleus or nucleator or a precise configuration of the described grain selector GS can also be computer-implemented or at least partially calculated, optimized or carried out by means of a computer program or a corresponding product.

4th shows in contrast to the representation of 3 that first Steiger 12 and / or feeder 13 on the molded body 11 were trained. This is best done on the surface 14th of the molded body 11 , but can also be partially within the molding 11 respectively. In particular, a position becomes the riser 12 and / or feeder 13 and the molded body 11 selected in such a way that essentially no pores or voids form during the heat treatment and any impurities or slag are displaced during the melting process.

A design and / or a position of the risers and / or risers on the molded body is established, for example, by or with the aid of the described computer program product 11 simulated. As a result, complicated calculations (computer-implemented) for the geometry of the risers or ventilation ducts or their position can be carried out expediently and specifically tailored to the component size, its material and the area of application. The same applies to the training or arrangement of the feeders. Corresponding manual invoices would be inefficient, if not impossible, or would lead to inadequate results.

Furthermore, in 4th to recognize that a shape 30th around the molded body 11 was built around, and this shape accordingly through external surfaces 14th of the molded body 11 is defined. Form 30th can be created in a single work step or in a large number of work steps, for example by sanding or spraying. The molding material of the mold 30th can be liquid or solid and include, for example, clay, ceramic, slip, quartz sand, zircon sand, synthetic binders and other materials. Form 30th can still be a green form. Form 30th should in any case be designed to keep the molded body dimensionally stable for a remelting or recrystallization process (see below). For this purpose or to achieve further advantages, the shape can include cooling plates, insulation or mechanical reinforcements.

By the curved arrow to the right of the 4th and the reference symbols T> T _{e are} intended to illustrate that further after the optional attachment of the riser 12 and / or feeder 13 , a heat treatment of the molded body 11 at a temperature T in the mold 30th takes place which is higher than a eutectic temperature. The heat treatment is preferably carried out or the temperature T selected such that a structural change, for example a recrystallization, a chemical change, a diffusion of structural components defining the strength or a remelting is effected at least in part. A melting point of the corresponding phase or of the material of the molded body does not necessarily have to be in this case 11 be crossed, be exceeded, be passed. Rather, the temperature T is preferably greater than a eutectic temperature T _e or a lowest solidus temperature of a material of the shaped body 11 elected.

A material of or for the shaped body is preferably used 11 chosen in such a way that chemical and / or metallurgical material changes that occur during the heat treatment with regard to a target structure of the component 10 be taken into account or offset. The choice of this material can also be made supported by a computer program product or a corresponding calculation or simulation.

In one embodiment, the molded body 11 constructed from a steel or a refractory metal or an alloy comprising a steel and / or a refractory metal.

5 preferably shows the component 10 after its heat treatment. The double hatching of the component is a contrast to the molded body 11 changed structure or a correspondingly changed or remelted structure with advantageously changed material properties, for example a significantly increased hardness, hot crack resistance, creep resistance or other properties. A correspondingly improved structure or structure can be determined by common methods of specific element, structure or material analysis, for example by X-ray fluorescence analysis or other destructive or non-destructive investigations.

After the component, as in 6th indicated, for example, by smashing its shape 30th has been freed and possibly completed by further post-heat treatment or post-processing steps, such as hot isostatic pressing, it preferably comprises (in contrast to the additively built-up structure) a cast-like structure, for example a directionally solidified or monocrystalline structure or a polycrystalline structure which is essentially free of pores and voids.

Based on 7th and 8th process steps of the method described and aspects of the component are based on a further, to the representations of the 3 to 6th alternative, designs described.

7th shows a heat sink 11 , the function of which is essentially to heat up a further component during operation to cool it. The additively constructed heat sink 11 preferably has funnel-shaped inlet openings 20th . These openings or channels can be via a not explicitly identified ring channel, which the rotationally symmetrical component in the Operation can be flown against, while the heat sink 11 rotates around its axis of rotation. The inlet openings can open into screw-like or helical cooling channels, the task of which is to transfer the heat from the component to a fluid that flows through it

As stated above, a plurality of feeders are exemplary 12 shown which, for example, regularly on a surface 14th of the heat sink 11 are arranged to serve their purpose during the heat treatment.

A single riser 12 is arranged in a similarly simplified manner centrally on the molded body in the vicinity of the axis of rotation. Accordingly, it can be provided within the scope of the present invention that the number of feeders 13 the number of risers 12 exceeds. This allows the material deposits to be fine over the surface 14th of the heat sink 11 be distributed and thus lead to a material supply that is as homogeneous as possible, whereas only one central point is sufficient as a riser.

In the 7th and 8th cooling channels shown 20th may have to be provided with a material core during the heat treatment (see reference number 15th ) are filled in order to define cavities provided in the design, since the cavities could otherwise be filled or displaced with molded body material and / or the component could lose its dimensional stability and / or function. This can occur in particular if the melting temperature of the material of the shaped body is exceeded during the heat treatment.

8th is a for 7th similar illustration, with the heat sink 11 however rotated and shown in perspective. It can be seen that the channels 20th have outlets (not explicitly identified by reference numerals) on the lower side of the component.

It can also be seen that feeder 13 also on a lateral surface of the heat sink 11 are arranged, and that the molded body 11 or the component 10 is designed ring-shaped.

The invention is not restricted to these by the description based on the exemplary embodiments, but rather encompasses any new feature and any combination of features. This includes in particular any combination of features in the patent claims, even if this feature or this combination itself is not explicitly specified in the patent claims or exemplary embodiments.

QUOTES INCLUDED IN THE DESCRIPTION

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

Patent literature cited

• EP 2601006 B1 [0006]

Claims (14)

A method for producing a component (10), comprising the steps: - a) additive manufacturing of a shaped body (11) for the component (10), in particular from a powder bed (P), - b) forming risers (12) and / or feeders (13) on the molded body (11), - c) producing a mold (30) around the molded body (11), the mold (30) being designed to keep the molded body (11) dimensionally stable for a remelting or recrystallization process, - d) heat treatment (T) of the shaped body (11) for the component (10) in the mold (30), so that a structural change is at least partially effected, and - e) removing the mold (30). Procedure according to Claim 1 , wherein the shape (30) is defined by outer surfaces (14) of the shaped body (11). Procedure according to Claim 1 or 2 , wherein the heat treatment of the shaped body (11) takes place at a temperature (T) which is greater than a eutectic temperature (T _e ) or a lowest solidus temperature of a material of the shaped body (11). Method according to one of the preceding claims, wherein a position of the risers (12) and / or feeders (13) and of the shaped body (11) is selected so that essentially no pores or voids form during the heat treatment and any impurities or slag during the heat treatment Melting process, in particular in a riser (12) are displaced. Method according to one of the preceding claims, wherein a design and / or a position of the risers and / or feeders on the molded body (11) is simulated. Method according to one of the preceding claims, wherein a material for the molded body (11) is selected such that chemical or metallurgical material changes that occur during the heat treatment are taken into account or compensated for with regard to a target structure of the component (10). Method according to one of the preceding claims, wherein the shaped body is constructed from a steel or a refractory metal or an alloy comprising at least one of these materials. Method according to one of the preceding claims, wherein the shaped body (11), in particular its surface (14), is specifically provided with a nucleating agent or a lack of nucleating agents during the additive manufacturing in order to provide a crystallization nucleus or crystallization during the heat treatment suppress. Method according to one of the preceding claims, wherein the heat-treated shaped body (11) is post-treated (f), for example by a further heat treatment and / or hot isostatic pressing. Method according to one of the preceding claims, wherein the additive manufacturing of the shaped body (11) takes place by means of selective laser melting. Method according to one of the preceding claims, wherein at least the production and removal of the mold (30) are carried out analogously to a casting process, in particular an investment casting process. Component (10) which can be produced or produced according to the method according to one of the preceding claims, further comprising a cast-like microstructure, for example a directionally solidified or monocrystalline microstructure or a polycrystalline microstructure that is essentially free of pores and voids. Component (10) according to Claim 12 , which is intended for use in the hot gas path of a gas turbine. Computer program product (CPP), comprising instructions which, when the program is executed by a computer, cause the computer to carry out the steps of selecting, simulating and / or providing one of the Claims 4 , 5 or 8.

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