DE102020109032A1 - Method and device for heating the component in the production of powder-melted metal components - Google Patents

Abstract

A method for the additive or generative production of metallic components (1), in which the component (1) is layered in a powder bed (24) by melting the particles forming the powder bed with at least one energy beam (15) from at least one energy source (14) a building platform (2) is built, the component (1) being heated and the component (1) being conductively or inductively flowed through by a current (50) during the layer-by-layer production, which leads to the component (1) being heated , one or more current paths (10, 50) being produced in the powder bed by selective melting of the powder material, and the power supply via the construction platform (2) via at least one current-conducting lead end (3) arranged in the construction platform (2) and at least one current-conducting discharge end (3) takes place, characterized in that during the layer-by-layer production of the component (1) in the powder bed next to the component (1) a powder-generated, electrically conductive vertical structure (38, 38a, b, c) is melted, which electrically connects any component layer at any height above the construction platform (2) to the power source (29)

Description

The invention relates to a method and a device according to the preamble of claim 1.

The invention accordingly relates to the generative production of three-dimensional objects that are built up in layers on a building platform in the powder melting process using a suitable energy source.

There are known methods and devices for the production of powder-melted components made of metal, for example from US Pat EP 3 013 502 B1 .

A preferred manufacturing method according to the invention is, for. B. the production of the components with a laser beam melting process.

Laser beam melting (SLM) is an additive manufacturing process in which components are produced in layers directly from a powdery material.

In the SLM process, the material powder is melted locally directly at the processing point using the thermal energy of a laser beam. To prevent the material from oxidizing, the work area is usually filled with a protective gas.

The starting material for the SLM process is a metal powder. It is applied as a thin layer (approx. 30 - 50 µm) to a substrate plate in a closed process chamber. According to the calculated areas of the CAD model, the powder is selectively melted with the laser beam using local heat input. Then the construction platform is lowered and a new layer of powder is applied. The next layer is selectively melted again with laser radiation and connected to the lower layer by melt metallurgy. The tailor-made component is thus created in layers from the powder material.

• • Verwendung von handelsüblichen Pulverwerkstoffen
• • (z. B. Edelstahl, Werkzeugstahl, Titan-, Aluminium-, Co- und Ni-Legierungen)
• • Vollständiges Aufschmelzen der Pulverpartikel mit dem Laserstrahl, wodurch eine Bauteildichte von ca. 100 Prozent erreicht wird.
• • Die für den Aufbau des Bauteils typischen Schichtstärken bewegen sich für alle Materialien zwischen 15 und 500 µm.

Essential features of the SLM process

• • Use of commercially available powder materials
• • (e.g. stainless steel, tool steel, titanium, aluminum, Co and Ni alloys)
• • Complete melting of the powder particles with the laser beam, whereby a component density of approx. 100 percent is achieved.
• • The layer thicknesses typical for the structure of the component range between 15 and 500 µm for all materials.

Due to these features, the mechanical parameters of the SLM components largely correspond to the specifications of the series material used. The finished component is - according to the state of the art - subjected to finishing and heat treatment, depending on the application, in order to achieve the required surface quality and dimensional accuracy as well as the desired structure with the corresponding mechanical properties. The disadvantage of this known - subsequent - heat treatment is, however, that it only takes place after the component has been completely manufactured, which has considerable disadvantages with regard to the internal connection of the layers during the manufacturing process and disadvantages with regard to the mechanical stress compensation between the layers.

However, the invention is not limited to a selective laser melting process having the features described above.

Electron beam melting is likewise claimed in the present invention.

(Selective) electron beam melting ((S) EBM) or electron beam sintering is a process for the production of metallic components from the powder bed. It is also one of the generative manufacturing processes.

Using an electron beam as an energy source, a metal powder is melted in a targeted manner, which means that compact components of almost any geometry can be produced directly from the design data. For this purpose, similar to selective laser melting, a powder layer is alternately applied to the previous one with a doctor blade and melted at certain points using an electron beam. In this way, the desired component is generated in layers.

In selective laser melting (SLM), the melt beam is controlled mechanically, whereas in electron beam melting the melt beam is deflected in a vacuum via a magnetic field (and thus inertia-free). This theoretically enables higher process speeds with the EBM compared to the SLM.

• Lasersintern ist ein generatives Schichtbauverfahren: das Werkstück wird Schicht für Schicht aufgebaut. Durch die Wirkung der Laserstrahlen können so beliebige dreidimensionale Geometrien auch mit Hinterschneidungen erzeugt werden, z. B. Werkstücke, die sich in konventioneller mechanischer oder gießtechnischer Fertigung nicht herstellen lassen.

However, the invention also relates to selective laser sintering, which is described below:

• Laser sintering is a generative layer construction process: the workpiece is built up layer by layer. Through the effect of the laser beams, any three-dimensional Geometries can also be generated with undercuts, e.g. B. Workpieces that cannot be manufactured using conventional mechanical or casting technology.

From the available CAD data of the component (usually in STL format), numerous layers are created by so-called "slicing".

Usually a CO2 laser, an Nd: YAG laser or a phase laser is used as a laser. The powdery material is a plastic, a plastic-coated molding sand, a metal or a ceramic powder or any other powder mixture.

A great advantage of the SLS is that support structures, as required in many other rapid prototyping processes, are not required. The component is always supported by the surrounding powder during its creation. At the end of the process, the remaining powder can then simply be tapped off and some of it can be reused for the next run. A complete reuse is currently not possible, especially with plastic powders, as these lose quality as a result of the process.

With the subject of EP 3 013 502 B1 or the equivalent DE 10 2013 212 620 A1 a method and a processing machine for generating a three-dimensional component by selective laser melting has become known, with a so-called process influencing device being present during the generation of the three-dimensional component, with the aim that the selective laser melting process is directly and locally influenced by a local and needs-based heat management is made possible. The cited publication provides that an electrical conductor is generated in the powder bed of the manufacturing device. which is subjected to a current flow to act on the already completed area of the component.

The electrical conductor makes contact with the already completed area of the component or is spaced apart from it. An electrical conductor that is in contact with the at least partially generated component at one or more points makes it possible to conductively heat the component or areas of the component of the not yet completely finished component by applying a current to the electrical conductor . In this way, the component generation can be thermally influenced before the component is completed. In this case, current is applied to the electrical conductor via its inlet and outlet ends by a supply device designed as a voltage generating device, so that heating takes place in the areas of the component through which current flows. In addition to direct, conductive heating of the component, the cited publication also proposes indirect heating by induction. In order to produce a conduction path in the areas of the partially produced component, the mentioned document provides that so-called functional interfaces are arranged in the building platform, which can be raised and lowered, which means that the building platform is penetrated by a number of bundles of cables, the bundles of cables being insulated electrical conductors penetrate the construction platform and protrude with their free, opposite ends into the powder bed.

The opposite, bent line ends of these electrical conductors, protruding horizontally into the powder bed, are then connected during the selective laser melting with electrical conduction paths that are generated from the powder bed. The conduction paths generated from the powder bed are therefore only directed horizontally and can only be arranged at certain vertical distances from one another, because their arrangement, distribution and size is determined by the fixed arrangement of the conductors that are firmly arranged in the powder bed and which enter the powder bed with their free cable ends protrude.

The powder-generated production of the conductor tracks in the powder bed and their contacting with the cable ends protruding into the powder bed has the disadvantage that, due to the limited number of cable bundles and their distribution, only a fixed arrangement of powder-bed generated conductor tracks is possible. The feed and discharge ends of the bundle of cables are insulated and passed through the construction platform and the conductors generated in the powder bed are contacted in the powder bed itself with the cable ends protruding there. In addition to the disadvantage that the number, position and cross-section of the conductor tracks is determined and cannot be freely selected, the further disadvantage is that a large number of bundles of cables must be passed through the building platform in isolation and the "skeleton", namely the tree-like structure , the conductive paths protruding into the powder bed must be present from the start, which greatly affects the intended use and the current flow of the conductive paths generated in the powder bed.

It is therefore difficult to freely define the heated areas of the component because the position of the powder-generated conductive paths in the powder bed is determined by the arrangement of the bundles of cables that protrude into the powder bed.

The bundle of lines protruding into the powder bed can therefore not be used mechanical support of the powder-generated component can be used.

With the subject of DE 10 2015 012 844 A1 basically the same method and device for the generative production of a three-dimensional molded body from a shapeless material by means of laser melting has become known. For the heat treatment of the partially manufactured component, a heating device is provided which is mounted so as to be displaceable relative to the layer thickness built up and the building platform. The heating device consists of a plurality of metering chamber heating elements; there are also heating elements for the process chamber. The process chamber heating elements can be arranged radially or in a star shape. The process chamber heating elements, which are in contact with the powder-generated molded body, are lowered by the respective height of the built-up layer thickness after each solidification step, so that there is again a flat plane for forming a new layer. Another embodiment also describes a heating device which is formed in layers together with the shaped body in a laser melting process. For this purpose, a building board with recesses is provided in the process chamber in which insulated and non-insulated insert elements are used at certain positions, depending on the position of the molded body and the heating device to be developed, depending on the position of the molded body to be formed and the heating device to be formed. The insulated insert elements are used at the points or recesses in the building board at which the heating device is to be formed, their arrangement running between power supply devices arranged separately from one another in the building board, so that a current bridge is formed between the power supply devices via the generatively designed heating device can be.

The one through the DE 10 2015 012 844 A1 The structure of the prior art described therefore does not go beyond the subject matter of the previously described EP 3 013 502 B1 out. The disadvantage here, too, is that the contact-bound line connection for the powder-generated line paths in the powder bed itself is made by fixed conductors protruding into the powder bed. This means that the heating zones for the component to be heated cannot be freely defined. Furthermore, there is the disadvantage that the current cross-section cannot be changed in relation to different layers in the powder-generated conductor tracks. Likewise, the current cross-section of the solid line wires protruding into the powder bed cannot be changed. The contact between conductor wires protruding into the conductor bed and conductor tracks produced generatively there has also proven to be difficult.

The invention is therefore based on the object of developing a method and a device of the type mentioned in such a way that a specific and freely selectable arrangement of heating zones on the component can be provided during the generative and layer-by-layer production of a component and that in particular the contact connection between the powder-generated Conductor tracks and the feed and discharge ends of the power supply device is improved.

In order to achieve the object set, the invention is characterized by the independent method claim 1.

A preferred embodiment with regard to a device used for this is the subject matter of independent claim 5.

The feature of the invention is that when the component is manufactured in layers, a powder-generated, electrically conductive vertical structure is melted in addition to the component in the powder bed. which electrically connects any component layer at any height above the building platform to the power source, whereby the powder-generated, electrically conductive structure is directly connected to current-carrying contact inserts in the building platform.

This is a major advantage over the EP 3 013 502 B1 , because in this publication a current-conducting structure is only described in the form of line wires which penetrate the building platform in an insulating manner, the current-carrying ends of which protrude into the powder bed. The line connections required in the powder bed for conductive power lines are then produced by melting powder bed particles onto the line ends protruding into the powder bed. This means that only horizontal current-carrying structures can be created in the powder bed.

The current-conducting, tower-like structure according to the invention, which is produced directly from the powder bed and which is directly connected in an electrically conductive manner to contact inserts in the construction platform, is missing. Line ends protruding into the powder bed have the disadvantage that they define a predetermined current-conducting line structure and there is no freedom to form any current-conducting, tower-like structures in any shape, dimension, height and spacing in the powder bed.

The term “tower-like structure” does not only mean a vertical structure of a conduction path generated in the powder bed, but also beyond that a certain cross-sectional shape, the z. B. can be designed in the manner of the profile of a fir tree. This means that the lower layers of the component, which are arranged next to the building platform and are in electrical contact with it, are supplied with larger current cross-sections than, in comparison, the layers of the component that adjoin them.

In an alternative embodiment, an inverted Christmas tree profile can also be used, which means that the layers of the powder-generated component lying next to the heat-conducting component platform are supplied directly from the contact inserts on the building platform with a smaller current cross-section than the layers above them, which are from the surface of the component platform are away.

The arrangement of the tower-like structure makes it possible to change the current distribution over different cross-sections of the vertical tower-like structure and thus to modify the current flow through the component to be heated at any point and at any height.

Another advantage of the method according to the invention is that the tower-like, current-conducting structure can at the same time also form the support structure for the component to be produced in layers. This is with the EP 3 013 502 B1 not the case.

A preferred device is the subject of independent claim 5. It is preferred if a powder-generated, electrically conductive vertical structure in the manner of a layer conductor is arranged next to the component when the component is manufactured in layers in the powder bed. The associated advantages have been described above.

The invention thus has the further advantage that the contact connections between the power supply and the powder-generated conductor tracks take place outside the powder bed and not inside via solid tree-like line structures, as is known from the prior art.

The preferred types of contact connections are the subject of subclaims 10 to 12.

The advantage of heating the component during generative production is that the connection points between the different layers that are deposited on top of one another are now strengthened and improved during production on any vertically superposed layers, because a line-based contact in the powder bed, as it was the technology is avoided. Overall, a stress-free, inherently solidified component is achieved because the desired heating already leads to a structural bond on the structure of the material during manufacture.

According to a preferred exemplary embodiment, the component is in particular a carbon-containing material, and it is known that heating in the range above 500 ° C. has to take place in order to improve the structural bond.

In one embodiment, the idea of the invention consists in, among other things, during the layer-by-layer production of the component, next to the component, a powder-generated, electrically conductive "tower" is melted in the powder bed, which connects any component layer at any desired height above the construction platform to a power source, so that the selected layer in the component is live and is heated accordingly. Such a “tower” is therefore a conductive structure that is melted from the powder bed and through which a current flows, the thermal output of which leads to the component being heated. So it is a wired power line through the component.

Instead of a conductive current flow through the tower-like structure with ohmic contacting of the component to be heated, it can be provided in another embodiment that the current-conducting structure does not contact the component, but rather encloses the component without contact, so that a conductive heating of the component when the current-carrying, tower-like structure takes place. The choice between conductive and inductive heating of the component applies to all of the previously described and all of the embodiments described below.

In a preferred embodiment, it is provided that each of the horizontal layers produced in succession or in parallel or alternatively - some - horizontal layers are flowed through in parallel with a conductive current, which is selected so high that sufficient heating of the single or several parallel layers can take place in the component.

In contrast to this prior art, the invention provides that the current-carrying layer conductor structure produced according to the invention can also be used as a mechanical support structure. This makes it possible to conduct a high-power current through the component in certain layer areas of the component in order to increase the temperature in this layer in the component in a targeted manner there, in order to change the structure there in a targeted manner.

The term “heat treatment” used here intends, among other things, to influence the structure in a targeted manner. Primarily, however, it is about a heat treatment in such a way that the heat generated by the flow of current is used to connect the layers of the component with one another in a targeted manner and to produce a low-stress component with low brittleness. This applies above all to the manufacture of hard metal components.

Tool steels have a high carbon content. This means that the steel is hard and can be used to machine other steels. When processing these steels, it is necessary to work in the austenitic range (around 723 ° C). Heating the component up to this temperature has the consequence that a component with low brittleness and low internal stress is produced (primary goal). The hardness obtained also plays a role, as the workpiece is subsequently heat-treated and thus reaches the required hardness. However, if there are tensions in the component, the workpiece would be warped in all directions after production.

• • größere Härte (Feinkornbildung)
• • geringere Sprödigkeit
• • höhere Duktilität (Zähigkeit)
• • geringere innere Spannungen

The conductive or inductive heating according to the invention has a positive effect on the following parameters:

• • greater hardness (fine grain formation)
• • less brittleness
• • higher ductility (toughness)
• • lower internal stresses

Because of the higher carbon content, hard metal requires a higher processing temperature. When processing low-carbon metals, the invention has the result that the temperature gradient over the entire component is lower / or zero and thus a (metallurgically) more homogeneous structure is created.

The invention accordingly relates to an embodiment in which the electrically conductive structure to be produced in the powder bed is used solely to heat the component.

The invention also includes embodiments in which support structures and additional current-carrying conductor tracks are created in the powder material.

• 1. Durch Kontakte direkt unterhalb des Bauteils (Stromeinleitung ohne Zwischenverbindung)
• 2. Durch das Einbringen von Leiterbahnen im Pulvermaterial
  • 2a) mit Türmen
  • 2b) mit Schlangenlinien
  • 2c) durch Querverbindungen
• 3. Durch die Verwendung von Stützstrukturen als Leiter

Additional current-carrying conductor tracks and contacts are therefore connected to the component. There are various options for implementing conductive or inductive heating:

• 1. Through contacts directly below the component (current introduction without interconnection)
• 2. By introducing conductor tracks in the powder material
  • 2a) with towers
  • 2b) with serpentine lines
  • 2c) through cross-connections
• 3. By using support structures as a ladder

1. 1. Die Bauplattform, auf der das Bauteil im generativen Prozess aufgebaut wird, wird durch einen konduktiv oder induktiv in das Bauteil eingeleiteten Strom temperiert.
2. 2. Der elektrische Leiter (Konduktor) im Bauraum der Maschine wird in Z-Richtung der Maschine dem Füllstand des Pulvers folgend bzw. mitbewegt.
3. 3. Der elektrische Strom wird über Kontakteinsätze in der Bauplattform von angeschlossenen Leitern an das Bauteil übertragen.
4. 4. Die Kontakteinsätze, die den elektrischen Strom vom elektrischen Leiter an das Bauteil übertragen, sind durch einen Isolatorwerkstoff von der Maschine elektrisch getrennt.
5. 5. Der Isolatorwerkstoff (z.B. aus Keramik) besitzt eine geringere spezifische wärme- und elektrische Leitfähigkeit als das Bauteil.
6. 6. Das Bauteil haftet mit Hilfe einer im Isolator integrierten Trägerschicht an der Bauplattform.
7. 7. Das Bauteil kann direkt auf dem Isolatorwerkstoff aufgebaut werden.
8. 8. Es kann eine separate Trägerschicht auf dem Isolator aufgebracht werden, welche die Verbindung zwischen dem Bauteil und dem Isolator herstellt.
9. 9. Die erste Ebene des Bauteils wird durch „Verkrallen“ des geschmolzenen Pulvers in den Poren des Isolatorwerkstoffes lagengesichert festgelegt.

The features of the invention listed in a list are summarized in the following points. In any combination with one another or on their own, they form the features of the invention:

1. 1. The building platform on which the component is built in the generative process is tempered by a conductive or inductive current introduced into the component.
2. 2. The electrical conductor in the installation space of the machine is moved in the Z-direction of the machine, following or moving along with the level of the powder.
3. 3. The electrical current is transferred from connected conductors to the component via contact inserts in the building platform.
4. 4. The contact inserts, which transmit the electrical current from the electrical conductor to the component, are electrically separated from the machine by an insulator material.
5. 5. The insulator material (eg made of ceramic) has a lower specific thermal and electrical conductivity than the component.
6. 6. The component adheres to the construction platform with the help of a carrier layer integrated in the insulator.
7. 7. The component can be built up directly on the insulator material.
8. 8. A separate carrier layer can be applied to the insulator, which creates the connection between the component and the insulator.
9. 9. The first level of the component is secured in position by "clawing" the molten powder in the pores of the insulator material.

The feature of the invention is that a powder bed is treated with an energy beam, which is arranged in a production room that is laterally bounded by the side walls of a building platform and on the bottom side by a liftable building platform in which at least two electrically conductive Contact inserts are arranged whose conductive surfaces protrude into the production area.

Through the formation of electrically conductive contact surfaces that protrude into the production area, it is possible to contact components that are generatively created in layers from the powder bed with these contact surfaces so that a current can flow through the component, which is preferably made of a conductive, carbonaceous building material .

Due to the applied current and the current strength as well as the current output that is generated between the at least two contact inserts in the production area, there is a current flow through the component, which is accordingly heated.

In the first embodiment, it is a conductive power line, which proceeds in a contact-bound manner from the at least two contact inserts, which are arranged either on the bottom side of the installation space or on the side surfaces of the installation space.

In a second embodiment, a conductive power line is provided through the powder-bed-generated, tower-like, power-carrying structure without the component being electrically contacted. In this case, it is a contactless, inductive heating of the component.

In all versions, a combination between contact inserts in the bottom side of the installation space and / or in the side surfaces of the installation space is possible.

It is important that the current flow is selected so high that a corresponding structural bond of the applied layer or several superimposed layers can take place in the component produced in layers and at the same time a mechanical stress equalization takes place.

A welding current source, which is used to generate the high electrical current required for arc welding, is used as a possible energy source for generating the heating current. The simplest welding power source is a welding transformer in the form of a short-circuit-proof leakage field transformer which supplies alternating current. In the case of welding power sources that supply direct current, this transformer is also supplemented with a rectifier.

In a preferred embodiment, a current is selected such as that used in a welding transformer for manual electrode welding of metals. In the case of a welding transformer, the alternating current of the network with high voltage and low amperage is converted into alternating current with low voltage and high amperage, which is required for welding. The welding current is regulated by taps on the primary coil of the mains transformer.

In a preferred first embodiment, a heating current flows through only the bottom surface and the layers of the component arranged closest to the bottom surface, so that of the contact inserts on the bottom and / or the side wall-side only the bottom and the layers closest to the bottom of the component are traversed by a suitable current flow in order to heat these layers in the required manner.

• Es wurde eingangs angegeben, dass es bevorzugt wird, einen solchen konduktiven oder induktiven Stromfluss zu wählen, der eine Erwärmung des Bauteils im Bereich von mehr als 500°C erreicht. Hierauf ist die Erfindung nicht beschränkt. Es kann eine niedrigere Temperatur oder auch eine wesentlich höhere Temperatur gewählt werden. Die Temperatur hängt von der Art und der Dimension des Bauteils ab, ferner von dessen Materialgefüge und dessen Materialzusammensetzung.

In another embodiment, a welding inverter can be used instead of a conventional welding transformer. The welding inverter is an electronic welding power source. Inverter welding machines are built for all arc welding processes such as electrode, MIG / MAG, plasma and WIG / TIG welding. The devices are connected to the mains with one or three phases, depending on their output. The basic principle of an inverter corresponds to a switched-mode power supply. The mains voltage is first rectified, chopped up with the help of power semiconductors with a frequency between 20 kHz and 150 kHz and transformed to a lower voltage via a relatively small transformer. The welding current must then be rectified using suitable diodes. The size of transformers of the same power is approximately inversely proportional to their working frequency, ie the higher the frequency, the smaller and lighter the transformer and the entire welding machine can be built. Inverter welding machines are more efficient than other welding power sources. Due to the higher working frequency, highly dynamic welding processes can be controlled much better. Various comfort functions can also be implemented:

• It was stated at the outset that it is preferred to select a conductive or inductive current flow that heats the component in the range of more than 500 ° C. The invention is not restricted to this. A lower temperature or a significantly higher temperature can be selected. The temperature depends on the type and dimension of the component, as well as its material structure and its material composition.

The choice of current type is also arbitrary. A direct current can be used or also an alternating current or three-phase currents. It is important that, according to the first embodiment, the bottom side and the layers of the component closest to the bottom side are heated so much by the current flow that a structural bond occurs and mechanical stresses that arise during the manufacture of the component in the composite layer are eliminated Component could result.

In a further development of the present invention, it is provided that the layers made away from the bottom of the component are also designed as mechanically stress-free as possible, so that a current can flow through higher layers that come from the bottom and the contact inserts arranged on the bottom or on the side wall. in the vertical direction - are removed.

For this purpose, the invention provides that electrically conductive layer conductors are produced in the powder bed from the material of the powder with the energy beam by producing such electrically conductive layer conductors with the energy beam from the powder material in addition to the component. In this embodiment it is no longer necessary for the bottom side of the component with electrical contact surfaces to be in contact with the current-generating contact inserts.

In the last-mentioned embodiment, it can therefore be provided that the component is arranged on the construction platform without any further electrical contact on the floor and that, in addition to the component, in the manner of a layer composite, current-conducting layer conductors are produced from the material of the powder, which with the help of the laser beam are generated so that they result in double-T structures approximately in cross-section, d. H. There are two parallel vertical base legs that extend at a distance from the component next to the component and are not directly connected to it, and there are one or more horizontal transverse legs that are electrically conductively connected to the vertical base legs and also carry current with individual or are connected to all layered side surfaces of the component.

The double-T-bar, which is designed horizontally, then connects with lateral contact surfaces to the side surface of a certain layer of the component and thus it is possible to use the double-T structure as a conductor and in any layer to the layer by layer to connect the component created and to heat the component at any desired height with a suitable heating current.

The formation of an electrically conductive structure as a double-T structure is only to be understood as an example. In the various exemplary embodiments of the invention, other structures are also described which are also designed in a meander-shaped, spiral-shaped or pyramid-shaped manner in order to influence the current conduction and the heating of certain layers in a targeted manner.
Thus, many contact surfaces can be applied safely to the side surfaces of the component.

In a variant of the invention, it is not absolutely necessary to provide the structures with the same electrically conductive cross section. Provision can be made for the electrically conductive, powder-melted structures to expand vertically upwards starting from the current introduction point in order to achieve an improved current density in an end of the component remote from the bottom-side contact surface.

As a result, a defined heating can be generated on desired layers of the component at any desired layer height in the component, which was not previously known.

The advantage of the measures according to the invention is accordingly that any desired layer component can be shaped by mechanical stresses by means of a suitable supply of heat from a current flowing through the component.

It is also stated that the only thing that matters is the power output, i.e. the supply of heat through a conductive current flow, which means that even relatively high voltages can be linked to high currents in order to achieve the required power output of e.g. B. to generate 2 kW to 100 kW on or in the component.

The numerical values given are not to be understood as limiting the invention and are intended to make it clear that the current power supplied is determined by the dimensions of the component to be manufactured in layers, by its material composition and by other parameters.

The given selective heating of the component, which can take place in layers, has the essential advantage that radiation sources that radiate contactlessly into the production area can be dispensed with.

For example, IR radiation sources or microwave radiation sources would heat the entire production space together with the powder bed, which would lead to clumping in the powder bed. The value of the invention is therefore to produce electrically conductive structures in the powder bed and to conduct such a high current through the electrically conductive structures that the component is freed from mechanical stresses during the layered build-up and otherwise to enable or improve the structural bond between the various layers.

It has been found that such a component is particularly difficult to handle, especially in the case of carbon-containing workpieces, and it has been found that in the manufacture of hard metal tools it is possible for the first time to produce such a hard metal tool in layers and through the required current conduction and the resulting power line Heating the layer structure to create a reliable connection between the various layers.

Thus, it is possible for the first time with the subject matter of the invention, for. B. to produce a hard metal cutter or other hard metal workpieces with high mechanical strength and service life.

For example, tungsten carbide particles and metal particles can be mixed into a powdery base material that forms the powder bed in order to create a heavy-duty hard metal tool.

In addition to the production of hard metal tools, other hard metal components can of course also be produced in a layer structure, such as B. shafts, axles, gears and the like.

This is a completely new manufacturing approach, which leads to high-quality, low-stress layered components through the selective, layer-by-layer heat supply via a conductive current.

The subject matter of the present invention results not only from the subject matter of the individual patent claims, but also from the combination of the individual patent claims with one another.

All information and features disclosed in the documents, including the summary, in particular the spatial configuration shown in the drawings, are claimed to be essential to the invention insofar as they are new, individually or in combination, compared to the state of the art.

In the following, the invention is explained in more detail with reference to drawings showing only one embodiment. Further features and advantages of the invention that are essential to the invention emerge from the drawings and their description.

• 1: Prinzipbild bei der generativen Herstellung eines Bauteils
• 2: eine Abwandlung des Prinzipbildes nach 1 mit Darstellung einer ersten Ausführungsform der Erfindung
• 3: eine gegenüber 2 abgewandelte Ausführungsform
• 4: eine gegenüber 3 abgewandelte weitere Ausführungsform
• 4a: Schnitt gemäß der Linie IVa-IV an 4
• 5: eine weitere Ausführungsform im Vergleich zu den Ausführungen nach 2 bis 4, bei welcher die Strompfade außerhalb des Bauteils angelegt sind
• 5a: Draufsicht auf den Schnitt nach 5
• 6: eine Draufsicht auf die Anordnung nach 7
• 7: Schnitt durch die Anordnung nach 6 mit Darstellung des fortschreitenden schichtweisen Aufbaus von stromführenden Schichtleitern im Pulverbett
• 8: die Fortschreibung des schichtweisen Aufbaus von Schichtleitern im Vergleich zur 7
• 9: die Draufsicht auf den Schnitt nach 10
• 10: Schnitt gemäß der Linie X-X in 9 mit einer Darstellung im Querschnitt abgewandelten Schichtleitern
• 11: die Fortschreibung des Schichtaufbaus nach X
• 12: die weitere Fortschreibung des Schichtaufbaus nach 10 und 11
• 13 und
• 14: Draufsicht und Schnitt auf eine weitere Ausführung der Strukturierung von stromführenden Schichtleitern
• 15 und 16: Draufsicht und Schnitt durch die Fortschreibung der Ausbildung von Schichtleitern
• 17 und 18: Draufsicht und Schnitt bei weiterer Fortschreibung des Aufbaus von Schichtleitern im Vergleich zu den 14 bis 16
• 19 und 20: Draufsicht und Schnitt durch ein weiteres Ausführungsbeispiel mit seitlicher stromführender Kontaktierung von Schichtleitern im Fertigungsraum
• 21: die Fortschreibung des schichtweisen Aufbaus von Schichtleitern im Fertigungsraum im Vergleich zur 20
• 22 bis 24: das Strom-Zeit-Diagramm des Stromflusses zur Erwärmung des Stroms, der die schichtweise, selektive Erwärmung des Bauteils erzeugt mit Darstellung verschiedener Stromformen

Show it:

• 1 : Schematic diagram of the additive manufacturing of a component
• 2 : a modification of the principle 1 showing a first embodiment of the invention
• 3 : one opposite 2 modified embodiment
• 4th : one opposite 3 modified further embodiment
• 4a : Section along the line IVa-IV 4th
• 5 : a further embodiment compared to the explanations according to 2 until 4th in which the current paths are created outside the component
• 5a : Top view of the section after 5
• 6th : a plan view of the arrangement according to 7th
• 7th : Section through the arrangement according to 6th with representation of the progressive layer-by-layer build-up of current-carrying layer conductors in the powder bed
• 8th : the continuation of the layered structure of shift supervisors compared to 7th
• 9 : the top view of the section after 10
• 10 : Section along the line XX in 9 with a representation of shift leaders modified in cross-section
• 11 : the continuation of the layer structure after X
• 12th : the further update of the layer structure after 10 and 11
• 13th and
• 14th : Top view and section of a further embodiment of the structuring of current-carrying layer conductors
• 15th and 16 : Top view and section through the continuation of the training of shift supervisors
• 17th and 18th : Top view and section with further update of the structure of shift leaders compared to the 14th until 16
• 19th and 20th : Top view and section through a further exemplary embodiment with lateral current-carrying contacting of layer conductors in the production room
• 21 : the continuation of the layer-by-layer structure of shift supervisors in the production room compared to 20th
• 22nd until 24 : the current-time diagram of the current flow for heating the current, which generates the layer-by-layer, selective heating of the component with the representation of various current forms

In 1 is a general principle of the generative structure and manufacture of a component 1 shown, which in a known manner in a powder bed 24 is built up and thereby on the surface of a machine table 8th in the direction of the arrow 26th Is designed to be lowered.

The powder bed 24 with the component manufactured in layers 1 defines the production area 34 one total with production unit 18th designated unit.

This production unit 18th this is used to manufacture the component 1 necessary material as powder material 12th through a wiper 13th fed in the direction of the arrow 23 and in the opposite direction via the production area 34 is guided and so in layers of powder material 12th on the top of the component 1 accumulates.

The powder material 12th becomes from a storage unit 17th taken from above a lifting table 20th a powder depot 19th forms in which the powder material 12th is in stock.

For removing the powder material in layers 12th through the wiper 13th becomes the lifting table 20th in the direction of the arrow 21 gradually raised in order to always have a defined layer of powder material 12th in the production room 34 of the production unit 18th bring to.

The layer-by-layer production of the component 1 takes place in the illustrated embodiment via an energy source 14th , which is designed, for example, as a laser. In the general description it was already mentioned that as an energy source 14th Not only can a laser be used, but other energy generating beams and associated energy sources.

What is important is the energy source 14th an energy beam 15th generated either via a mirror 16 or via some other deflection optics onto the surface of the production area 34 is directed and there as an energy beam 15th the powder material 12th changed in such a way that the component is built up in layers 1 results.

The manufacturing room 34 is laterally through the side walls 25th and on the bottom side through the top of the machine table 8th limited that gradually in the direction of the arrow 26th can be lowered.

Based on such an exemplary representation in 1 , which only describes the SLS process, it should be noted that the invention is not limited to the SLS process, but also relates to other generative, layered production methods of components, such as. B. the electron beam melting mentioned in the general description or the selective laser sintering.

The following exemplary embodiments are therefore to be understood on the premise that the other methods mentioned can also be used in the same way.

In 2 a first simple embodiment of the invention is now shown. In the build platform 2 that are on the machine table 8th is arranged is an insulator 5 arranged in which at least two contact inserts 4th are embedded, which carry a high current and are arranged so as to isolate that a short-circuit current in the insulator 5 is avoided.

The two contact inserts 4th are with electrical conductors 3 and a suitable power source, which power source can be a direct current source or an alternating current source or a three-phase current source. The current 50 standing over the electrical conductor 3 should flow in the component 1 live current paths 10 train so that the component 1 between contacts 4th is electrically conductively contacted. This takes place via the contact surfaces that develop there 41 that is between the bottom side of the component 1 and the top of the contact inserts 4th develop.

It is preferred if the insulator 5 has a relatively rough surface, for example as a pore layer 27 is designed, so that with a layered structure of the molten powder material from the powder bed, each layer of the component, which is on the bottom surface of the component in the area of the pore layer 27 begins to connect with this pore layer 27 takes place.

This ensures a mechanically favorable anchoring of the component 1 at the top of the isolator 5 to avoid the wiper 13th the previously made layer tears off when he applies the next layer.

The one used to heat the component 1 Current paths created in the powder material by melting the powder material 10 of the stream 50 accordingly extend arcuately through the component 1 through, and due to the current flow through the electrically conductive component, there is a heating in the component and consequently a layer-by-layer heating of each individual layer in the component.

Several layers in the component are heated together so that - depending on the thickness of the layer - z. B. also 3, 4 or 5 layers at the same time from those in the component 1 unfolding rivers 10 of the stream 50 be heated.

The heating temperature is chosen so that it is lower than a melting temperature of the powder in the powder bed 24 to caking the powder bed 24 due to the heating of the component 1 to avoid.

Even if you look at the component temperature 1 close to the melting temperature of the powder material in the powder bed 24 comes, the powder only melts on the surface 49 of the component 1 take place, but not on the side areas. The melting on the surface 49 but is preferred when the next layer of powder material is on the component 1 is applied because this results in a better layer bond.

the 3 shows the same components and description as in 2 , only that in a modification of the exemplary embodiment according to 2 additionally in the isolator 5 an insulator insert 6th is arranged, in the insulator material finely divided powder particles 31 are integrated, so that it is a hybrid insulator in which the meltable powder particles 31 of the powder bed 24 are arranged.

This has the advantage that the adhesion is in the area of the binding layer that is being formed 28 no longer due to a layer of pores 27 - as in 2 shown - arises, but that a real fusion bond in the area of a binding layer 28 towards the hybrid isolator insert 6th takes place, which is thus on the component 1 adheres and against lateral displacement movements by the wiper 13th is specially protected.

Here are the ones in the component 1 unfolding current paths 10 of the stream 50 shown as double current paths - just as in 2 - To make it clear that the embodiment shown can also be an alternating current that comes from the power source 29 about the electrical conductors 3 in the contact inserts 4th is fed in.

Of course, it is possible to change the number of contact inserts 4th to enlarge and a total of z. B. 3 or 4 contact inserts to be arranged, all with the same power source 29 are connected.

In another embodiment, however, it can also be provided that two different current sources for two different or the same currents 50 are present and that perpendicular to the current paths shown 10 there are more in the component 1 extending current paths are available, so that the current paths shown 10 in 3 Current paths extending perpendicular to this can also be present via contact inserts (not shown in detail) and a further current source (not shown in detail).

This multiple power source with multiple contact inserts and multiple contacting of the component 1 Otherwise applies to all exemplary embodiments.

the 4th and 4a show a further embodiment of the contacting of the component 1 in connection with the contact inserts on the bottom 4th .

It is shown there that the contact inserts 4th solid and conductive with associated contact tips 30th are connected, which are approximately pointed or wedge-shaped and an electrically insulated carrier layer 7th penetrate. In the carrier layer 7th are - as in the previous embodiment 3 - powder particles 31 arranged, which ensure that it melts the first layer of the component 1 on the carrier layer 7th to a good connection between the top of the carrier layer 7th and the bottom side of the component 1 comes to this mechanically and secured in position in the powder bed 24 to anchor.

the 4a shows the multiple tip arrangement of the contact tips 30th which from the tops of the contact inserts 4th go out and are electrically connected to these.

the 5 and the following show - in a departure from the exemplary embodiments of FIG 2 until 4th - That it is not necessary to make electrical contact on the bottom side of the component 1 with assigned contact inserts 4th to create.

The exemplary embodiments to be described below relate to the fact that the current-carrying contact inserts 4th protrude into the powder bed and form part of the production room 34 are and initially no electrical connection with the component 1 exhibit. The component 1 is accordingly upwards in the component space 32 built up and from the limits of the component space 32 there is a lateral distance 33 to the closest contact-making side of the in the production area 34 protruding tops of the contact inserts 4th . In 5a the distance 33 also drawn.

Of course, a combination of the exemplary embodiments is also possible 1 until 4th (bottom-side contact with the component) with the Embodiments of the 5 ff (lateral contact with the component) possible.

To now a power line outside of the component space 32 lying electrically conductive, powder-melted structures in the component 1 to generate into it, the invention provides, according to a further exemplary embodiment, that now electrically conductive layer conductors 35 in the powder bed through the energy beam 15th the energy source 14th are generated, resulting in a layered structure of approximately tower-like, current-carrying layer conductors 35 comes from the molten powder material.

This is in the 6th until 8th shown.

In the 7th it can be seen that starting from the top of the build platform 2 the component 1 in the area of its component space 32 in the powder bed 24 is formed in layers, but that next to the component 1 - at a horizontal distance from it - in the powder bed electrically conductive tower-like layer conductor 35 can also be built up in layers. In 7th is only shown that this shift leader 35 different layers 38 , 38a, 38a, 38c, which are all fused together to conduct electricity and to conduct electricity via associated contact surfaces 41 with those outside the component space 32 lying contact inserts 4th are connected.

It is important that the shift supervisor - in this version - designated as a double-T 35 in the horizontal direction by T-shaped connecting webs 36 are electrically connected, which are laterally attached to the component 1 conductive via contact surfaces 40 connect. Here, too, is the current path 10 shown, which is approximately U-shaped through the two parallel, layered layer conductors 35 extends and in the horizontal direction over the horizontally adjoining connecting webs 36 the component 1 interspersed.

the 7th shows, as a further production step, the further layered structure of the layer conductor 35a, which has an associated contact layer 39 , which is melted there, is continuously covered with further layers, which are indicated by way of example as 38a, 38c. The further layer conductor 35b produced in this way has not yet flowed through it.

This takes place in the next process step, which is described in 8th is shown, where it can be seen that the layer conductor 35b was built up with the layer structure 38c, which is connected via horizontal connecting webs 36 with assigned contact areas 40 electrically conductive applied to the side surfaces of the component in order to allow a selective current flow through different layers of the component 1 to enable.

the 8th accordingly shows two selective current flows through the component 1 , which are all operated in parallel, the upper current path 10b being formed at a distance from the lower current path 10a and it can be seen therefrom that different layers of the component 1 are selectively traversed by the heating current.

the 8th also shows that in the further progress of the method a further layer conductor is built up above the layer conductor 35b, which does not yet contribute to the current flow, this layer conductor 35c, however, later via horizontal connecting webs formed there 36 with defined layers of the component 1 over the contact surfaces 40 is electrically connected.

the 9 until 12th show that it is not necessary for the solution that the tower-like shift ladder designed as a double-T 35 , 36 must have the same current cross-section.

the 10 , 11 and 12th show that such shift supervisor 45 can also have different cross-sections, the layer conductors in the exemplary embodiment shown 45 starting from the bottom surface of the component 1 have a conical increase in cross-section vertically upwards in order to better current distribution in the component 1 to enable.

In this way, improved regulation of the heat generated in the component in layers can be ensured.

the 10 shows a process progress, as it is also shown, for example, in 7th is shown.

the 11 shows that in this exemplary embodiment, too, several layer conductors 45a, 45b, 45c lying one above the other are connected to one another in an electrically conductive manner via assigned connecting layers and between them - each related to a specific layer - form connecting webs 46a, 46b, 46c, so that this electrically conductive structure creates a particularly favorable power distribution through the component 1 generated and therefore an equalization of the in the component 1 generated heat is achieved.

The heat loss generated by the flow of current through the component can therefore be adjusted through the design of the dimension, length, cross-section and conductor track routing. The cross-sectional shape of the powder-melted line structures can be modified within wide limits. Instead of a rectangular structure similar to a conductor track, round, semicircular, elliptical, square and other cross-sectional shapes can also be produced.

Between the stacked shift leaders 45 are each current-carrying contact layers 39 formed from the molten powder material, so that from a material-integral structure and a material-integral continuation of the layered layer conductors 35 can be spoken.

This also applies to the cross section of the connecting webs shown here 47 , which have different cross-sections lying vertically on top of one another, the lower connecting web 47 a smaller current-carrying cross-section than the connecting web above it 47 having. This is in 12th shown.

This is just one example of the fact that the heat output in the component to be heated 1 should be distributed as evenly as possible going up from the bottom side.

However, this is not necessary for the solution. In another embodiment, it can also be provided that the lower connecting web 47 has the largest conductive cross-section and all connecting webs above it 47 have a smaller cross-section and the cross-sections continuously increase or decrease.

This therefore depends on the type and strength of the heat output generated in the component 1 away.

In the 14th until 17th Various exemplary embodiments are shown, which show that it is not necessary to solve the problem, the electrically conductive structures in the powder bed 24 Form a double T-shape. The embodiments according to 13th until 17th show that such structures can also be designed in a meandering shape, as is the case with the connecting webs, for example 46 in the 13th until 17th is shown. These are designed in a meandering shape and consequently also form current paths running in a meandering manner 10 the end.

The connecting bridges 46 , which preferably extend in the horizontal direction in the powder bed, are therefore z. B. also meander-shaped.

the 14th shows the generated current flow.

Advantage of the meandering design of the horizontal connecting webs 36 , 46 is that, depending on the height of the desired electrically conductive layer, this layer can also be interrupted and a completely different layer can be laid over it, as shown in 15th is shown.

This is done in 15th produced in that the connecting webs located in the lower layer 36 are retained, but short-circuit-like overlying, straight connecting layers 48 are provided that the current flow with lower current flow resistance in other layers of the component 1 give in. This is in 15th shown. During the installation of a conductive structure in a layer, it is possible to modify or interrupt the conductive structure below.

the 16 and 18th Incidentally, show that the horizontal connecting layers too 48 do not necessarily have to run horizontally. They can also run obliquely in the XYZ plane, as shown in the 16 and 18th is shown. There it can be seen that the connecting layers are separated from a wide double-T-shaped horizontal connecting web 36 obliquely upwards into the component 1 extend into it to a variation of the current flow through the component 1 to reach.

the 18th shows that the approximately pyramid-shaped connecting layers 48 , 48a, 48b can also have different cross-sections and different shapes. In any case, a current flow is always generated through the pyramid-shaped connecting layers 48a, 48b, as shown in FIG 18th indicated by dashed lines. From this - and in connection with 17th - the result is that it is possible within free limits, in any layer of the powder bed 24 create an electrically conductive structure of any shape and type and this with electrically conductive contact surfaces with the side walls of the component 1 to connect in order to conduct a heating current through the component in different defined layers of the component.

the 19th until 21 show as a modified embodiment that the invention is not limited to bottom-side contact inserts 4th to use that directly or indirectly with the component 1 be contacted electrically conductive.

the 19th until 21 show that in addition to or on their own in addition to the contact inserts arranged on the bottom 4th also on the side in the side wall 25th of the production room 34 arranged contact inserts 4a can be arranged, which in the same way - as described above - by melting in the powder bed 24 live with assigned shift supervisors 35 can be connected.

These shift supervisors 35 lay themselves on the side walls of the component in an electrically conductive manner 1 and it is preferred that such horizontal layer conductors 35 now lying on top of each other in layers can be formed and the component is selectively traversed by the current flow in a specific layer, as shown in FIG 21 is shown.

There it can be seen that there is only one upper layer in the component 1 from the heat-generating electricity in the shift supervisor 35 is traversed while the lower shift leader 35 because of the lowering of the machine table 8th is removed from the area of current flow.

In this way, too, it is possible to selectively heat layers of the component in layers 1 via laterally brought contact inserts 4th to reach.

The embodiments according to 19th until 21 can in any way with the embodiments according to 2 until 18th be combined. Accordingly, the combination protection from all the illustrated exemplary embodiments is also claimed in any combination with one another or individually.

the 22nd until 24 show various exemplary embodiments of suitable current flows, which of course can also be electrically regulated as a function of temperature. The current flow is preferably regulated as a function of the heating of the component and can, for example, according to the current-time diagram in 22nd from an approximately continuous at position 43 rising current curve 42a exist, which at position 44 is switched off again to at position 43 to be switched on again after a certain period of rest.

Another possible current flow is, for example, in 23 given, where a pure rectangular current is shown on the current curve 42b.

It is also in position according to the current-time diagram 24 an arc-shaped stream is possible.

The current output (heat output) resulting from hatching is in the 22nd until 24 drawn. A common alternating current with a frequency of 50 Hz can be used. It is thus possible to use direct currents, and currents with a higher frequency can also be used.

The current, the voltage and the resulting power, which is a measure of the heating power in the component, are freely selectable and depend on the required physical conditions, in which way the component produced in layers is to be heated in which layer.

Incidentally, the invention is not based on the use of a single energy beam 15th from a single source of energy 14th limited. It can be provided that a first energy beam 15th for the production of the component in layers 1 is used and that with a second different energy beam or further energy beams the electrically conductive structure layer by layer from the powder bed 24 is produced.

It can also be provided that the composition of the powder in the powder bed 24 is changed in one horizontal layer at a time. For example, the powder composition at the locations where the electrically conductive structure is melted from the powder bed can be different from, in comparison, the powder composition at the locations where the metallic component 1 is produced.

List of reference symbols

1

Component

2

Build platform

3

Electrical conductor

4th

Contact insert a

5

insulator

6th

Insulator insert

7th

Carrier layer

8th

Machine table

9

Insulator insert

10

Current paths a, b, c

11

Rung section

12th

Powder material

13th

wiper

14th

Energy source

15th

Energy beam

16

mirrors

17th

Storage unit

18th

Production unit

19th

Powder depot

20th

Lift table

21

Direction of arrow

22nd

Got over

23

Direction of arrow

24

Powder bed

25th

Side wall

26th

Direction of arrow

27

Pore layer (of 5)

28

Tie layer (of 6)

29

Power source

30th

Contact tip

31

Powder particles

32

Component space

33

distance

34

Manufacturing room

35

Shift supervisor a, b, c

36

Connecting bridge

37

Radial area (powder)

38

Layer a, b, c

39

Contact layer

40

Contact surface (top)

41

Contact surface (below)

42

Current curve a, b, c

43

position

44

position

45

Shift supervisor a, b, c

46

Connecting web a, b, c

47

Connecting bridge

48

Link layer a, b

49

Surface (of 1)

50

current

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 3013502 B1 [0003, 0019, 0026, 0031, 0036]
• DE 102013212620 A1 [0019]
• DE 102015012844 A1 [0025, 0026]

Claims (14)

A method for the additive or generative production of metallic components (1), in which the component (1) is layered in a powder bed (24) by melting the particles forming the powder bed with at least one energy beam (15) from at least one energy source (14) a building platform (2) is built, with a conductive or inductive heating of the component (1) takes place, and the component (1) is flowed through during the layer-by-layer production of a current (50), which leads to a heating of the component (1) , one or more current paths (10, 50) being produced in the powder bed by selective melting of the powder material, and the power supply via the construction platform (2) via at least one current-conducting lead end (3) arranged in the construction platform (2) and at least one current-conducting discharge end (3) takes place, characterized in that when the component (1) is produced in layers in the powder bed, one on both sides Powder-generated, electrically conductive vertical structure (38, 38a, b, c) arranged next to the component (1) or at least partially enclosing the component is melted, which conducts any desired component layer at any desired height above the construction platform (2) with the power source (29 ) connects and that the electrical contacting of the electrically conductive structure (38, 38a, b, c) takes place on the construction platform (2). Procedure according to Claim 1 , characterized in that the powder-generated electrically conductive structure is designed as a tower-like layer conductor (38). Procedure according to Claim 1 or 2 , characterized in that the tower-like powder-generated electrically conductive structure is designed as a mechanical support structure for supporting the component (1). Method according to one of the Claims 1 until 3 , characterized in that the first level of the component (1) is secured in position on an insulator (5) sunk in the construction platform (2) by "clawing" the molten powder in the pores of the insulator material of the insulator (5). Device for the additive or generative production of metallic components (1), in which the component (1) is layered in layers in a powder bed (24) by melting the particles forming the powder bed with at least one energy beam (15) from at least one energy source (14) a building platform (2) is built, with a conductive or inductive heating of the component (1) takes place, and the component (1) is flowed through during the layer-by-layer production of a current (50), which leads to a heating of the component (1) , one or more current paths (10, 50) being produced in the powder bed by selective melting of the powder material, and the power supply via the construction platform (2) via at least one current-conducting lead end (3) arranged in the construction platform (2) and at least one current-conducting discharge end (3) takes place, characterized in that in the layer-by-layer production of the component (1) in the powder bed in addition to the Ba uteil (1) a powder-generated, electrically conductive vertical structure (38, 38a, b, c) is arranged in the manner of a layer conductor (35) and that the electrical contacting of the electrically conductive structure (38, 38a, b, c) by contact inserts (4 , 4a) takes place on the construction platform (2). Device according to Claim 5 , characterized in that the current-carrying vertical and horizontal conductor tracks (35, 45) and contacts (39, 40, 41) connected to the component (1) are formed from the melted particles (31) of the powder bed (24). Device according to Claim 5 or 6th , characterized in that the electrically conductive contact (3, 4, 41) of the component (1) is arranged on the surface of the construction platform (2). Device according to one of the Claims 5 until 7th , characterized in that the electrically conductive contacting of the component (1) takes place through layer conductors (35, 45) melted in the powder bed (24). Device according to one of the Claims 5 until 8th , characterized in that the electrically conductive, powder-melted structures, starting from the current introduction point, expand vertically upwards in the manner of an inverted fir tree profile in order to achieve an improved current density in an end of the component remote from the bottom contact surface. Device according to one of the Claims 5 until 9 , characterized in that at least one insulator (5) is arranged in the construction platform (2), through which the conductors (3) for supplying power to the current-carrying structure (38) reach. Device according to one of the Claims 5 until 10 , characterized in that the component (1) is produced on the surface of at least one insulator (5), and that the surface has a rough surface designed as a pore layer (27). Device according to Claim 11 , characterized in that at least one insulator insert (6) carrying the component is arranged in the insulator (5), in the insulator material of which finely distributed meltable powder particles (31) are integrated Device according to one of the Claims 5 until 12th , characterized in that for electrical contacting of the bottom side of the component (1) in connection with the contact inserts (4) arranged on the bottom side, the contact inserts 4 are firmly and conductively connected to associated contact tips (30) which are approximately pointed or wedge-shaped and have a penetrate electrically insulated carrier layer (7). Device according to one of the Claims 5 until 13th , characterized in that the layer conductor (35b) is applied to the side surfaces of the component (1) in an electrically current-conducting manner via horizontal connecting webs (36) with associated contact surfaces (40) in order to enable a selective current flow through different layers of the component (1) .

Images