WO2020043419A1 - Layering apparatus for the additive manufacture of at least one component region of a component, method for operating such a layering apparatus, and storage medium - Google Patents

Abstract

The invention relates to a layering apparatus (10) for the additive manufacture of at least one component region of a component (40) by means of an additive layering method. The layering apparatus (10) comprises a process chamber (20), within which there are arranged: at least one construction field (I) for constructing the component region in layers from a material (56); at least one flow-guiding device (16) which comprises at least one channel (36) having an outlet opening (14a) for introducing a shielding gas into the process chamber (20); and a gas outlet device (30) which is stationary relative to the construction field (I) for discharging the shielding gas from the process chamber (20). The flow-guiding device (16) is designed, during operation of the layering apparatus (10), to arrange an end region of the channel (36) of the flow-guiding device (16) comprising the outlet opening (14a) above a plane of the construction field (I) and to move said end region relative to the plane of the construction field (I) in such a way that at least a predominant part of the protective gas can be guided locally over a sub-region of the construction field (I) in a main flow direction (H) at least substantially parallel to the plane of the construction field (I). The invention also relates to a method for operating such a layering apparatus (10), and to a storage medium having a program code for controlling such a layering apparatus (10).

Description

 Layer construction device for additive manufacturing of at least one component area of a component, method for operating such a layer construction device and storage medium

description

The invention relates to a layer construction device for additive manufacturing of at least one component area of a component, a method for operating such a layer construction device and a storage medium with a program code for controlling such a layer construction device.

In so-called additive or generative manufacturing processes (so-called rapid manufacturing or rapid prototyping processes), a component area or a complete component, which can be, for example, a component of a turbomachine or an aircraft engine, is built up in layers. Mainly metallic components are usually manufactured by fiber or electron beam melting or sintering processes. First, a mostly powdery material is applied in layers in the area of a construction field or a build-up and joining zone in order to form a powder layer. The material is then solidified locally by supplying energy to the material in the area of the construction field by means of at least one energy beam, as a result of which the material melts or sinters and forms a component layer. The energy beam is controlled as a function of a layer information of the component layer to be produced in each case. The layer information is usually generated from a 3D CAD body of the component and subdivided into individual component layers. After the molten material has solidified, the building platform is lowered layer by layer by a predefined layer thickness. Then the steps mentioned are repeated until the desired completion of the desired component area or the entire component. The component area or the component can in principle be produced on a construction platform or on an already generated part of the component or component area or on a support structure. The advantages of this additive manufacturing are, in particular, the possibility of being able to produce very complex component geometries with cavities, undercuts and the like in a single process. The fact that zones with swirling of the powder layer or dust, as well as other contaminants such as condensate, smoke or spatter, often form uncontrollably on the construction site, on melted powder or on already solidified areas of the Deposit component layer. This can lead to corresponding impurities, inclusions and process disruptions and ultimately ultimately to a reduction in component quality.

In order to reduce such problems, it is known to lead protective gas via a channel to a ceiling of a process chamber of the layer construction device used in order to generate a global protective gas stream, that is to say to the entire construction field, which flows from above into the process chamber Construction site directed and discharged via a global gas outlet arranged in the process chamber in the area of the construction field to prevent the rise of smoke, dust, condensate and the like and to transport away any contamination. However, the protective gas flow must not be set too strongly, since it would otherwise stir up the powder layer. Such a global shielding gas flow is therefore only effective to a limited extent against the contaminants mentioned.

The object of the present invention is to provide a layer construction device and a method for operating such a layer construction device, which enable a process-reliable additive production of component layers of a component of higher quality. Another object of the invention is to provide a storage medium with a program code which ensures appropriate control of such a layer construction device.

The objects are achieved according to the invention by a layer construction device with the features of claim 1, by a method for operating such a layer construction device according to claim 14 and by a storage medium according to claim 15. Advantageous refinements with expedient developments of the invention are specified in the respective subclaims, advantageous refinements of each invention being seen as an advantageous embodiment of the other aspects of the invention and vice versa. A first aspect of the invention relates to a layer construction device for the additive production of at least one component region of a component by an additive layer construction method. The layer construction device has a process chamber within which at least one construction field for layer-by-layer construction of the component region from a material, at least one flow control device which comprises at least one channel with an outlet opening for introducing a protective gas into the process chamber, and a gas which is stationary with respect to the construction field - Outlet device for removing the protective gas from the process chamber are arranged. A process-reliable additive production of component layers of a component with a higher quality is achieved according to the invention in that the flow guiding device is designed to arrange and, during operation of the layer building device, an end region of the channel of the flow guiding device comprising the outlet opening, ie a gas inlet, above a level of the construction field and to be moved relative to the level of the construction field in such a way that at least a predominant part of the protective gas can be conducted locally over a partial region of the construction field along a main flow direction that is at least substantially parallel to the level of the construction field. In other words, in contrast to the prior art, it is provided that the flow control device does not generate a global, but rather a local, protective gas stream, which accordingly does not affect the entire construction site, but only a sub-area of the construction site. In other words, the local protective gas flow does not flow within a volume of the process chamber that lies above the entire area of the construction field, but only within a volume of the process chamber that lies above a partial area of the construction field. The partial area or partial area can basically have an area that is 90%, 89%, 88%,

87%, 86%, 85%, 84%, 83%, 82%, 81%, 80%, 79%, 78%, 77%, 76%, 75%, 74%, 73%,

72%, 71%, 70%, 69%, 68%, 67%, 66%, 65%, 64%, 63%, 62%, 61%, 60%, 59%, 58%, 57%, 56% , 55%, 54%, 53%, 52%, 51%, 50%, 49%, 48%, 47%, 46%, 45%, 44%, 43%,

42%, 41%, 40%, 39%, 38%, 37%, 36%, 35%, 34%, 33%, 32%, 31%, 30%, 29%, 28%, 27%, 26% , 25%, 24%, 23%, 22%, 21%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%,

12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1% or less corresponds to the total area of the construction site, with corresponding intermediate values to be regarded as also disclosed . The extent of the local protective gas flow is determined in such a way that in the area of a projection starting from the outlet opening of the channel, a flow speed is above a predetermined minimum speed and / or a volume flow is above a predetermined minimum value and / or a mass flow is above a predetermined value The minimum value lies and / or a flow direction lies within a predetermined maximum deviation, both a horizontal and a vertical expansion of the local protective gas flow being taken into account. Preferably, when determining the extent of the local protective gas flow, only a volume of the process chamber above the construction field that is close to the construction field is considered. For example, the predetermined minimum speed can be 30% or 50% of the maximum speed after the process gas has emerged from the outlet opening. For example, the predetermined maximum deviation of 30 ° or 45 ° relative to the flow direction that the protective gas flow has when exiting the outlet opening, by means of these criteria, the local protective gas flow can, for. B. from turbulence or un directed gas movements within the process chamber, but also from a globally overflowing protective gas stream according to the prior art. Due to the movability of the outlet opening, the proportion of the area of the partial area of the construction field over which protective gas flows can be varied one or more times during a layer construction method carried out with the aid of the layer construction device. A simple way of setting the maximum possible partial area can be done, for example, by a corresponding choice or setting of the horizontal dimension of the outlet opening. Furthermore, the protective gas flow is generated by means of the flow guiding device in such a way that its main flow direction after exiting from the outlet opening of the channel is not perpendicular to the construction field, but rather at a distance parallel or approximately parallel to the construction field or to a plane which comprises the construction field is. Under an at least substantially parallel main flow orientation of the protective gas flow, in addition to exactly parallel main flow orientations, that is to say exactly parallel to an x / y plane of the layer construction device, main flows arranged also are slight, that is to say main flow orientations deviating from an exactly parallel orientation by ± 20 ° understand, for example, be by 1 °, 2 °, 3 °, 4 °, 5 °, 6 °, 7 °, 8 °, 9 °, 10 °, 11 °, 12 °, 13 °, 14 °, 15th °, 16 °, 17 °, 18 °, 19 ° or 20 ° deviating main flow orientations, each measured at the outlet opening of the channel or an inlet device of the channel. The main flow orientation of the protective gas flow can be determined, for example, by the arithmetic mean of a number of flow directions, the individual flow directions or lines, for. B. measured, simulated or otherwise determined. However, the deviations should generally be limited to angles at which it is ensured that the protective gas flow is conducted over the powder layer at a distance from the powder layer and that the latter is not affected. belt or otherwise impaired. In this way, contaminants can be removed particularly reliably, since a comparatively strong protective gas flow can be generated directly in the region of the contaminants without the powder layer being undesirably whirled up. The at least essentially parallel alignment also avoids the previously required deflection of a protective gas flow directed perpendicular to the construction field. Any spreading or fanning out of the protective gas flow after exiting the channel can be tolerated and adequately controlled over short distances, for example by appropriate alignment and design of the outlet opening of the channel and by controlling the flow rate or the volume flow of the protective gas. Since the flow guide device according to the invention can also be moved relative to the construction field, the channel or its outlet opening can, if necessary, be positioned where most impurities occur at a certain point in time. Since only a local shielding gas stream has to be generated, the shielding gas volume required is also considerably less than in the case of global shielding gas streams, as a result of which the flow control device according to the invention can be implemented more easily and causes lower operating costs. The channel is preferably formed as tubing or piping, which is connected, for example, via an interface in a wall of the process chamber to a gas supply arranged outside the process chamber, from which gas is transported within the channel to the outlet opening. The process chamber of the layer construction device comprises a cavity above the construction site, the construction site generally forms part of a floor area of the process chamber. The process chamber comprises (in particular vertically) ascending walls, the arrangement of which is often a z. B. follows a rectangular outline of the construction site and keep a certain distance from the construction site. The cavity of the process chamber is closed from the top by a ceiling that z. B. be formed horizontally, but can also include slopes. The gas outlet device can be arranged in a wall of the process chamber and / or adjacent to or near an edge of the construction field. The inlet opening of the gas outlet device generally forms an essentially vertical interface between a cavity of a gas outlet downstream of the inlet opening and a cavity formed by the process chamber.

In summary, the flow guide device according to the invention enables a protective gas flow over a distance between the mobile outlet opening of the channel and the stationary one To direct gas outlet device. In this way, the spreading of contaminants within the process chamber can be prevented particularly effectively and the contaminants can be removed more quickly and directly to the gas outlet device. Use of the flow control device in conjunction with the immovable gas outlet device also advantageously makes it possible to dispense with one or more mobile or local gas outlet device (s) that can be moved relative to the construction site. In general, "one / one" within the scope of this disclosure should be read as indefinite articles, ie without "explicitly stated otherwise" always as "at least one / at least one". Conversely, "one / one" can also be understood as "only one / only one". Any suitable gas or gas mixture that does not lead to a deterioration in the component quality under the respective manufacturing conditions can generally be used as protective gas. For example, the protective gas can comprise or be argon and / or another noble gas or noble gas mixture (He, Ne, Kr, Xe). The protective gas preferably has minimal impurities in oxygen, nitrogen, hydrogen and water (steam). The lowest possible contamination means contents of at most 20 ppm, in particular of at most 10 ppm or less.

In an advantageous embodiment of the invention it is provided that the layer construction device comprises a powder supply for applying at least one powder layer of the material in the area of the construction field and / or at least one radiation source for generating at least one energy beam for layer-by-layer and local melting and / or sintering of the material Forming a component layer by selectively irradiating the material with at least one energy beam. The layer construction device can, for example, basically be designed as a selective laser sintering and / or laser melting device and have one or more lasers as the radiation source (s). To generate a laser beam as an energy beam, for example, a CO2 laser, Nd: YAG laser, Yb fiber laser, diode laser or the like can be provided. It is also possible that the device is designed as an electron beam sintering and / or melting device, that is to say has one or more electron sources as radiation source (s) for generating an electron beam as an energy beam. Any combinations of electromagnetic radiation and particle radiation are also conceivable. Depending on the material used and the radiation strategy, melting and / or sintering of the material can occur during irradiation, so that in the context of the present invention the term “welding” also means “sintering” and vice versa can be understood. Preferably, the energy beam (s) are coupled or let into the process chamber via one or more areas of the process chamber wall and / or process chamber ceiling (e.g. coupling window) that are transparent to energy beams and cross the cavity of the process chamber on its way to the construction site, where it or . they effect the selective solidification of the material locally.

In a further advantageous embodiment of the invention, it is provided that the flow guide device comprises at least one guide surface segment for limiting a spread of the protective gas introduced into the process chamber. With the aid of the at least one guide surface segment, the typical spread of an unguided protective gas flow can be limited on one, two, three or more sides and / or the protective gas flow can be directed. This means that contaminants can be removed more precisely and effectively. The at least one guide surface segment provides, in a structurally simple manner, a pressure side which is geometrically optimally adaptable to the respective application and by means of which the protective gas flow can be limited and / or directed in a desired direction. In its simplest configuration, the guide surface segment can be designed as a “guide plate” or guide plate, wherein the guide surface segment can in principle be formed from metallic and / or non-metallic materials or composite materials. Furthermore, the guide surface segment can be straight or curved depending on the desired flow guidance. The at least one guide surface segment is preferably designed as a component of the flow guide device that is separate from the channel or its outlet opening. As a result, a distance between the guide surface segment and the outlet opening can be variably set. This represents a considerable gain in flexibility due to the ability to coordinate the relative movements of the outlet opening and the guide surface segment within the process chamber.

It can be provided that the at least one guide surface segment is at least regionally (high) energy beam transparent, in particular laser transparent. This makes it possible, for example, to form a flow guide channel through which the material can nevertheless solidify due to the (high) energy beam-transparent property of the guide surface segment. For example, the guide surface segment can be partially or completely laser-transparent, so that a laser beam can be guided through the guide surface segment onto the material in order to selectively solidify it. Likewise, ne electron beam transparent embodiment can be provided. Alternatively or additionally, the at least one guide surface segment consists at least in regions of a non-induction material, in particular of a high-temperature-resistant plastic, of a ceramic, of a composite material or of any combination thereof. In this way, the guide surface segment can advantageously be used in connection with inductive heating devices or be arranged in the vicinity thereof, without causing an undesired heating of the guide surface segment due to induced currents. In the context of the present disclosure, a high-temperature-resistant plastic is understood to mean high-performance plastics with high temperature resistance, which have a continuous use temperature of at least 150 ° C., in particular of at least 300 ° C. An example of such a high-performance plastic is polyether ether ketone (abbreviated PEEK), which belongs to the group of polyaryl ether ketones and has a melting temperature of about 335 ° C. However, other high-performance plastics, combinations of several high-performance plastics and composite materials with one or more high-performance plastics can generally also be used to produce the guide surface segment. Other suitable non-induction materials, such as ceramic materials, can also be used. In general, however, non-magnetic metals or metal alloys can also be provided.

It has been shown to be advantageous if the at least one guide surface segment has a longitudinal extent of at least 50%, preferably at least 70% and particularly preferably at least 100%, that is to say 50%, 51%, 52%, 53%, 54 %, 55%, 56%, 57%,

58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%,

73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%,

88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 100% or more of a construction site side and / or a construction site diameter of the construction site . As a result, the proportion of the distance between the outlet opening of the channel of the flow guide device, which acts as a local gas supply, and the inlet opening of the gas outlet device, along which the flow guide device guides the protective gas flow at least in sections, can be optimally adjusted and, if necessary, in a corridor over the entire length of the construction site (100 %) can be realized. As an alternative or in addition, it is provided that the at least one guide surface segment and the end region of the channel of the flow guide device which comprises the outlet opening can be moved relative to one another. This allows the outlet opening for example, are moved along the guide surface segment, the guide surface segment permanently limiting and guiding the inert gas flow.

Further advantages result from the fact that the flow guide device comprises at least two guide surface segments which are arranged opposite one another and / or which limit an outlet opening of the channel of the flow guide device for the protective gas in relation to the construction site. As a result, the inert gas flow can be limited on two or more sides and be conducted. By arranging the at least two guide surface segments to be fixed relative to one another or movable relative to one another, either a constant or a changeable limitation or flow guidance of the protective gas flow can be realized. For example, two or more guide surface segments can be moved translationally relative to one another, for example displaceable and / or telescopic into one another, in order to allow a variable geometry of a flow channel formed or limited by the guide surface segments. This enables optimized flow control with differently dimensioned component layers. Alternatively or additionally, two or more guide surface segments can be rotated relative to one another, for example tilted or pivoted, in order to realize a limitation or deflection of the protective gas flow.

In a further advantageous embodiment of the invention it is provided that at least one guide surface segment at an angle between 60 ° and 120 °, that is to say for example at an angle of 60 °, 61 °, 62 °, 63 °, 64 °, 65 °, 66 °, 67 °, 68 °, 69 °, 70 °, 71 °, 72 °, 73 °, 74 °, 75 °, 76 °, 77 °, 78 °, 79 °, 80 °, 81 °, 82 ° , 83 °, 84 °, 85 °, 86 °, 87 °, 88 °, 89 °, 90 °, 91 °, 92 °, 93 °, 94 °, 95 °, 96 °, 97 °, 98 °, 99 °, 100 °, 10P, 102 °, 103 °, 104 °, 105 °, 106 °, 107 °, 108 °, 109 °, 110 °, 111 °, 112 °, 113 °,

114 °, 115 °, 116 °, 117 °, 118 °, 119 ° or 120 °, is arranged to the construction site. In other words, the guide surface segment is arranged perpendicular (90 °) to the construction field or to a plane which encompasses the construction field, with inclinations of up to ± 30 ° being possible. As a result, the spread of the protective gas flowing essentially parallel to the construction site can be limited on one or more sides and directed or, if necessary, deflected. For example, the protective gas flow can be limited or directed transversely to the main flow direction, that is to say perpendicularly, with a deviation of up to ± 30 °. This allows the spreading of the protective gas flow on one or more sides and a more precise and effective removal of impurities. It can further be provided that based on the construction site has a highest point of at least one guide surface segment during operation of the layer construction device a greater distance from the construction site than a highest point of an outlet opening of the channel of the flow guidance device. In other words, the control surface segment - measured at right angles from the construction site - projects over the outlet opening at least in some areas. As a result, overflow of the guide surface segment and thus a deterioration in its conductivity are advantageously prevented. For example, it can be provided that at least one guide surface segment, in whole or in part, based on the construction site, is at least 1 cm, that is to say for example by 1.0 cm, 1.1 cm, 1.2 cm, 1.3 cm, 1.4 cm, 1.5 cm, 1.6 cm, 1.7 cm, 1.8 cm, 1.9 cm, 2.0 cm, 2.1 cm, 2.2 cm, 2.3 cm, 2.4 cm, 2.5 cm, 2.6 cm, 2.7 cm, 2.8 cm, 2.9 cm, 3.0 cm, 3.1 cm, 3.2 cm, 3.3 cm, 3.4 cm, 3.5 cm, 3.6 cm, 3.7 cm, 3.8 cm, 3.9 cm, 4.0 cm, 4.1 cm, 4.2 cm, 4.3 cm, 4.4 cm, 4.5 cm, 4.6 cm, 4.7 cm, 4.8 cm, 4.9 cm, 5.0 cm,

10 cm, 15 cm, 20 cm or more, extends over the highest point of the outlet opening. In other words, the guide surface segment projects above the outlet opening in the direction away from the construction field, as a result of which an “overflow” of the protective gas flow and thus a deteriorated protective gas flow guidance are reliably prevented.

As an alternative or in addition, it is provided that, based on the construction site, a lowest point we at least one guide surface segment in operation of the layer construction device has a smaller distance from the construction site than a lowest point of an outlet opening of the channel of the flow guide device. This advantageously prevents an underflow of the guide surface segment and thus a deterioration in its conductivity and any swirling of the material. It can be provided that at least one guide surface segment at a distance of at least 0.5 cm and / or at most 5 cm, that is to say for example of 0.5 cm, 0.6 cm, 0.7 cm, 0.8 cm, 0.9 cm, 1.0 cm, 1.1 cm, 1.2 cm, 1.3 cm, 1.4 cm, 1.5 cm, 1.6 cm, 1.7 cm, 1.8 cm, 1.9 cm, 2.0 cm, 2.1 cm, 2.2 cm, 2.3 cm, 2.4 cm, 2.5 cm, 2.6 cm, 2.7 cm, 2.8 cm, 2.9 cm, 3.0 cm, 3.1 cm, 3.2 cm, 3.3 cm, 3.4 cm, 3.5 cm, 3.6 cm, 3.7 cm, 3.8 cm, 3.9 cm, 4.0 cm, 4.1 cm, 4.2 cm, 4.3 cm, 4.4 cm, 4.5 cm, 4.6 cm, 4.7 cm, 4.8 cm, 4.9 cm or 5.0 cm above the material or construction field or can be arranged. This ensures that the guide surface segment is at a sufficient distance from the material and does not disturb or otherwise disturb it even when it is moved over the material. At the same time, it is ensured that contaminants arising in the area of the material, for example smoke or Spatter formation, can be reliably detected by the inert gas flow and removed.

The outlet opening of the channel and at least two guide surface segments of the flow guide device are preferably designed and oriented to one another such that, in operation, the two guide surface segments on opposite sides of the outlet opening are preferably arranged parallel to one another and spaced apart such that they frame the outlet opening or delimit it on both sides , wherein the outlet opening can preferably be moved along (for example in a direction parallel to) a longitudinal extension of the guide surface segments.

In a further advantageous embodiment of the invention, it is provided that at least one guide surface segment of the flow guide device forms an upper side in relation to the construction field and / or that at least one guide surface segment of the flow guide device forms a lower side in relation to the construction field. This makes it possible to control the flow of protective gas upwards and / or downwards and to define the limits of the expansion of the gas flow upwards, that is to say away from the construction site, and / or downwards, that is to say towards the construction site. Furthermore, with the aid of the guide surface segment or the guide surface segments, a channel which is predominantly or completely closed in cross section can be formed, which enables particularly efficient and trouble-free removal of contaminants. In order to nevertheless ensure the passage of an energy beam used to solidify the material onto the construction site, it has proven to be advantageous if at least one guide surface segment of the flow guide device clears a passage opening for an energy beam, at least during operation of the layer construction device. This ensures that a line of sight is released for the energy beam, so that it is not hindered by the direction of flow and can strike the construction field from a ceiling area of the device through the passage opening and can selectively solidify the material. In general, two or more passage openings can also be provided, which release one or more lines of sight between the construction field and a ceiling area of the process chamber or an entry area of the energy beam of the radiation source into the process chamber. The passage opening (s) in the simplest embodiment can be cutouts or holes in the relevant guide surface segments through which both the energy beam and gas pass. can occur, whereby congestion effects are advantageously avoided. Alternatively, at least one passage opening can be formed from a gas-impermeable material that is transparent to the energy beam.

In a further advantageous embodiment of the invention it is provided that a position of the flow guide device within the process chamber relative to the construction field as a function of a position of a contact surface of the energy beam and / or as a function of a position, orientation or expansion of a current working area of the energy beam within the construction field , e.g. B. a radiation strip or checkerboard field or generally a localized radiation zone as a partial area of a cross-sectional object to be irradiated in a layer, on the construction field is adjustable and / or that the flow control device at least substantially simultaneously with the impact surface of the energy beam on the construction field or with the work area is movable relative to the construction site. As a result, contaminants, which predominantly arise when the energy beam hits the material, can be removed particularly reliably.

Further advantages result from the fact that at least one guide surface segment has a changeable geometry and / or by the fact that at least one longitudinal extent of the flow guide device can be set. This enables a particularly flexible adaptation to different construction site and component geometries. For example, the guide surface segment can have a bendable or bendable guide surface. Likewise, shape changes by hinges, a glazing curtain or the like are conceivable in order to direct the protective gas flow along a non-linear flow path. A longitudinal extent of the flow guiding device can be changeable, for example, in that one or more guiding surface segments can be telescoped.

In a further advantageous embodiment of the invention, it is provided that the layer construction device comprises a further flow guiding device in the area of an upper side of the process chamber, by means of which a global protective gas flow with an essentially perpendicular main flow direction can be generated in relation to the construction field. The process chamber can thus be filled with a protective gas atmosphere during the layer construction process, the protective gas atmosphere preferably having a pressure between 50 mbar and 1200 mbar, that is to say for example with 50 mbar, 100 mbar, 150 mbar, 200 mbar, 250 mbar, 300 mbar, 350 mbar , 400 mbar, 450 mbar, 500 mbar, 550 mbar, 600 mbar, 650 mbar, 700 mbar, 750 mbar, 800 mbar, 850 mbar, 900 mbar, 950 mbar, 1000 mbar, 1050 mbar, 1100 mbar, 1150 mbar or 1200 mbar in the process chamber can be provided. The protective gas in the protective gas atmosphere can preferably have the same or a similar composition as the protective gas stream discharged from the local flow control device over the construction site. For example, argon can be used both for the protective gas stream and for the protective gas atmosphere. It can be provided that the protective gas discharged from the local flow control device is filtered after removal via the gas outlet device in order to remove discharged pollutants, and is then used as a protective gas for the global protective gas atmosphere in the process chamber. The protective gas atmosphere in the process chamber can basically be carried out in a circuit that may be provided with a filter system in order to avoid losses. Due to the first, local flow control device, the flow rate or the volume flow of the protective gas can be reduced compared to layer construction devices without such a local flow control device, whereby turbulence of the material can be prevented particularly reliably.

In a further advantageous embodiment of the invention, a support device is provided, by means of which at least the end region of the channel of the flow-guiding device comprising the outlet opening and / or at least one guide surface segment can be moved in at least one spatial direction relative to the construction field within the process chamber. This represents a structurally simple possibility for positioning the outlet opening and / or at least one guide surface segment with respect to the construction field. The carrying device is preferably arranged partially or completely within the process chamber. The end region of the channel and / or the guide surface segment can in principle be fixed directly or indirectly to the carrying device. The carrying device is preferably designed in such a way that it can avoid any coater or a powder feeder for applying a layer of powder to the building site or that the carrying device and the coater can be moved over the building site without interfering with one another. For this purpose, the carrying device and the coater can, for example, be movable in mutually perpendicular travel directions at similar height levels or can be moved at different height levels above the construction site. Further advantages result from the fact that the carrying device comprises at least two supporting arms, each movable relative to the construction field. The support arms can each have one or more degrees of freedom of translation and / or one or more degrees of freedom of rotation. The first support arm can preferably be moved in exactly one first spatial direction and the second support arm can be moved in the first spatial direction and in a second spatial direction, the second spatial direction being perpendicular to the first spatial direction. For example, it can be provided that one of the support arms can be moved in the y-direction of the process chamber, while the other support arm can be moved in the x-direction, the x and y directions being defined by the side edges of the construction field. Preferably, at least one guide surface segment is coupled to one of the support arms, so that it moves with it during operation, while the end region of the channel of the flow guiding device comprising the outlet opening is coupled to the other support arm, so that the outlet opening moves with it during operation . In the same way, the at least one guide surface segment and / or the end region of the channel comprising the outlet opening can be moved independently of the construction field, for example by means of a robot arm. The inlet opening of the gas outlet device preferably has a horizontal dimension which essentially corresponds to a horizontal dimension of an adjacent construction site side, particularly preferably has at least the length of the immediately adjacent construction site side. This embodiment proves to be advantageous, for example, when the at least one guide surface segment can be moved or moved only in a single spatial direction relative to the construction site and this spatial direction essentially corresponds to the orientation of a longitudinal extension of the inlet opening. As a result, the local gas flow and impurities in the process chamber atmosphere that are carried along or displaced by it, regardless of the position of the flow guide device, ie the channel, its outlet opening and / or the or the guide surface segments, relative to the construction field directly in the direction of or up to Inlet opening of the gas outlet device is transported and then removed from the process chamber Pro.

In a further advantageous embodiment of the invention, it is provided that the layer construction device comprises a heating device, by means of which the construction field can be tempered at least in some areas. As a result, even materials that are difficult to melt, such as, for example, highly heat-resistant nickel-base superalloys, Mg ₂ Si alloys and intermetallic compounds such as titanium aluminides, can be processed using the layer construction device. be used, as these materials can be preheated with the help of the heating device and preheated to temperatures close to their melting point. Furthermore, already solidified material can be heat-treated and / or cooled in a controlled manner with the aid of the heating device. The heating device can in principle comprise one or more radiant heaters (IR, microwave, etc.) and / or one or more inductive temperature control devices in order to heat electrically conductive areas in the process chamber of the layer construction device with the help of one or more induction elements due to eddy current losses.

In a further advantageous embodiment of the invention it is provided that the heating device comprises at least a first induction coil and a second induction coil, the first induction coil being fixed on the first support arm and the second induction coil on the second support arm. As a result, the magnetic fields of the induction coils can be selectively superimposed in order to carry out a temperature-controlled adjustment of a selected area of the construction field. The induction coils can be moved independently of one another. The second induction coil is preferably made smaller than the first induction coil and can only be moved within an area delimited by the first induction coil. In a further embodiment, the at least two induction coils can be movable relative to one another in a translatory and / or rotary manner, as a result of which their relative positioning with respect to one another can be set particularly precisely and as required. This permits a correspondingly precise heating of the material or the component layer, in that the magnetic fields of the induction coils can be deliberately superimposed in the desired areas.

In a further advantageous embodiment of the invention, a drive of the heating device is also used synergistically for driving the flow guide device and / or the introduction device. This is advisable because a heating area of the heating device and a flow target area of the flow guide device and / or the introduction device are arranged at least immediately adjacent to one another, ie adjacent to one another, in the process chamber. They preferably form an intersection at least in an orthogonal projection of the heating area and the flow target area onto one level of the construction field. In other words, under certain conditions, a target work area to which the heating device is moved in the horizontal direction can also be a target work area of the flow guide device and / or the introduction device and vice versa. In particular, under the intersection understood a partial area of the construction site. The heating area is understood in particular to mean a volume of solidified or unconsolidated material which is heated directly or indirectly by the heating device. It is taken into account that, for example, when using an inductive heating device, an uppermost layer of the unconsolidated material on the construction site can be heated largely indirectly (by heat conduction) by heat from a directly heated solid body lying below the uppermost material layer or solidified beforehand Area in the environment, ie in the surrounding material. From the use of this principle for heating one or fewer material layers that lie / lie between a component or a construction platform and the process chamber atmosphere, it can be seen that the indirectly heated area, which by definition is above a predetermined minimum temperature, has a very small spatial extent may have the z. B. a few or a few dozen micrometers (at least in a vertical direction perpendicular to the construction field). This also means that the indirectly heated, locally limited area below the surface of the material (including the surface) moves with a corresponding amount even with a slight horizontal displacement of the directly heated area located below. The flow target area is understood as a partial volume of the process chamber that connects to the construction field immediately above the construction field. Preferably, the flow target area comprises a surface of the uppermost layer of the material on which a gas stream strikes, or along which a gas stream flows, or over which a gas stream flows. It is taken into account here that a gas flow introduced into the process chamber by means of the introduction device arranged outside the material generally does not essentially have a depth effect into the material, that is to say essentially does not penetrate below the surface of the uppermost material layer. A position or movement of the heating device and the heating area generated by it thus determines a position or movement of the flow target area defined by the flow guide device and / or the introduction device. The position or movement of the heating device and / or the flow guide device and / or the inlet device is preferably controlled or regulated in such a way that intersections of the flow target area with the construction field and the heating area with the construction field occur at least during one step of processing the material ( e.g. in the form of selective consolidation) form as large an intersection as possible. If, for example, the above-mentioned “cross coil” is used as the heating device, which comprises two inductors that can be moved relative to one another in order to be able to overlay the individual induction fields, the introduction device requires for the outlet opening, ie the gas inlet, which limits one locally Process gas stream generated, its own drive or support arm or at least must be movable in such a way that it can be moved or moved with the overlapping area of the two inductors, that is to say the most intensive heating area of the heating device.

In this embodiment of the heating device, it can then be provided that the inlet device and / or the flow guide device are attached indirectly or directly to the induction coils or respectively indirectly or directly to an induction coil or jointly to an associated support arm of the support device. It can also be provided that the introduction device and / or the flow guide device can be moved at least together with the induction coils or the respectively assigned induction coils with the aid of one or more separate support arms. A common process with the induction coils fully fulfills the objectives of the guided flow depending on the heating area, in particular with regard to the avoidance of undesirable contamination in the assembly and joining area.

A further independent inventive concept lies in coupling the mobility of the flow guide device and / or the introduction device to a selected operating mode of the flow and / or the heating. This can be controlled or regulated, for example, with the aid of a suitably designed control device or control unit of the layer construction device. For example, a first, “active” operating position can be provided, in which the local gas inflow and the conduction of the local gas flow take place. This operating position of the heating device and the flow guiding device and / or the introducing device above the construction field is suitable for heating or Flow and, as described above, can provide mobility in all degrees of freedom or limited to degrees of freedom that are appropriate for the respective application. In a second, "inactive" operating position, on the other hand, there is no local gas inflow or no conduction of the local gas. current. This operating position preferably includes moving the flow guiding device and / or the introducing device into an area outside the travel movement of a coater of the layer building device, in order not to hinder the application of a new powder layer. For example, a method or moving the heating device and / or the flow guiding device and / or the introducing device into a lateral parking position and / or moving or pivoting upward (z-direction) into the free space of the process chamber can be provided. Moving upwards in particular offers the advantage of high operational reliability, since in a region of the process chamber that is close to the ceiling or away from the construction area, typically neither the coater nor other components are moved, and there is therefore no need for additional coordination. The “inactive” operating position can also be selected, for example, during the set-up, cleaning, flooding, etc. of the layer construction device or during non-process times. This control or regulation of the operating positions of the heating device and / or the flow control device and / or the introduction device generally represents its own aspect of the invention, which can be implemented independently of the other aspects of the invention.

Further advantages result from the fact that the end region of the channel of the flow guide device comprising the outlet opening and / or at least one guide surface segment is fixed on the heating device and / or that the end region of the channel of the flow guide device comprising the outlet opening and / or at least one guide surface segment is dependent a movement of the heating device is movable. Since the heating device is used for tempering an area to be solidified, an area in the solidification process and / or an already solidified area of the component to be manufactured, a common arrangement or mobility is advantageous, since this ensures that the protective gas is always available for component quality particularly relevant area of the material. Any contaminants are removed particularly reliably, so that a particularly high component quality is guaranteed.

A particularly precise alignment of the main flow direction of the protective gas is achieved in a further embodiment in that the end region of the channel of the flow guiding device comprising the outlet opening comprises a nozzle. The length of the nozzle can have a constant opening cross-sectional area, alternatively the opening cross-sectional area can widen, taper or have complex geometries.

In an advantageous embodiment of the invention, it is provided that the flow guide device is designed to, during operation of the layer construction device, the main flow direction of the To direct shielding gas onto the at least one inlet opening of the gas outlet device in such a way that the main flow direction has an inclination of at most 30 °, for example 30 °, 29 °, 28 °, 27 °, 26 °, 25 °, 24 °, 23 °, 22 °, 21 °, 20 °, 19 °, 18 °, 17 °, 16 °, 15 °, 14 °, 13 °, 12 °, 11 °, 10 °, 9 °, 8 °, 7 °, 6 °, 5 °, 4 °, 3 °, 2 °, 1 ° or 0 ° relative to a plane parallel to the construction site, preferably relative to a horizontal. In other words, it is provided that the main flow direction of the shielding gas flow or a virtual line connecting the outlet opening and the inlet opening is oriented at least approximately parallel to the construction field or horizontally, so that the shielding gas together with any entrained contaminants is correspondingly low in deflection and turbulence to lead over the construction site and lead away from the process chamber. In addition to a particularly reliable removal of interfering particles, undesired process gases, etc., this also particularly reliably prevents undesirable fluidization of the material, since the protective gas flow is not directed or redirected to a wall, ie to a flow resistance. This can increase the component quality accordingly. Alternatively or additionally, it is provided that the flow guiding device is designed to direct the main flow direction of the protective gas toward the at least one inlet opening of the gas outlet device during operation of the layer construction device such that the main flow direction is arranged parallel or coaxially to a normal of an opening cross section of the inlet opening of the gas outlet device is. In other words, it is provided that the surface or plane of the outlet opening and the surface or plane of the inlet opening are at least substantially parallel to one another during operation of the layer construction device. This allows a particularly low-swirling introduction and extraction or removal / discharge of the protective gas and any entrained contaminants from the process chamber.

In a further advantageous embodiment of the invention it is provided that the outlet opening of the channel and / or the at least one inlet opening of the gas outlet device during operation of the layer construction device is arranged closer to the construction field than to a process chamber ceiling. In other words, it is provided that the outlet opening of the flow guide device and / or the inlet opening of the gas outlet device is or are arranged close to the construction site during operation, i.e. closer to the construction site than to the process chamber ceiling, preferably in a lower half of the process chamber, more preferably in the lowermost third and particularly preferred in lowest quarter of a clear height, ie a maximum inner height, of the process chamber (vertical or perpendicular to the construction site).

A second aspect of the invention relates to a method for operating a layer construction device according to the first aspect of the invention, in which before, during and / or after an additive production of at least one component region of a component by an additive layer construction method by means of the flow guide device of the end region comprising the outlet opening Channel of the flow control device is arranged above the level of the construction field and is moved relative to the level of the construction field in such a way that at least a predominant part of the protective gas emerging from the outlet opening is directed locally over a partial region of the construction field along a main flow direction parallel to the construction field. In this way, a more process-reliable additive production of component layers of a component with a higher component quality can be achieved, since before, during and / or after the solidification of a component layer, a targeted, locally limited removal of swirled material, dust, condensate,

Smoke, spratzem and / or other contaminants is safely admitted by means of the local protective gas flow. The inert gas stream is preferably introduced or injected at a predetermined distance from the powder layer and at least substantially parallel to the construction site, that is to say in the x / y plane of the layer construction device (± 30 ° deviation from the x / y plane, ie possible in the z direction) to prevent the material from being whirled up unintentionally. This is a structurally simple and inexpensive way to reliably keep at least from selected areas and in particular the current solidification stand or the current working area of the at least one energy beam by a directed, local protective gas flow of smoke, condensate or other contaminants. Any suitable gas or gas mixture that is compatible with the respective production conditions can generally be used as the protective gas. For example, the protective gas can comprise or be argon and / or another noble gas or noble gas mixture (He, Ne, Kr, Xe). The protective gas preferably has as little contamination of oxygen, nitrogen, hydrogen and water (steam) as possible. The lowest possible level of contamination means contents of at most 20 ppm, in particular of at most 10 ppm or less. To carry out the method according to the invention, the layer construction device can comprise a basically optional control device. The control device can have a processor device which is set up to implement an embodiment of the invention Procedure. For this purpose, the processor device can have at least one microprocessor and / or at least one microcontroller. Furthermore, the processor device can have a program code which is set up to carry out the embodiment of the method according to the invention when it is executed by the processor device. The program code can be stored in a data memory of the processor device. In the context of the present disclosure, the expression “trained to” is to be understood in such a way that not only is it general suitability, but that specifically hardware and / or software-based measures are implemented and configured to carry out the respective steps mentioned. Further features and their advantages result from the description of the first aspect of the invention, advantageous configurations of the first aspect of the invention being regarded as advantageous configurations of the second aspect of the invention and vice versa.

A third aspect of the invention relates to a storage medium with a program code, which is designed to control a layer construction device according to the first aspect of the invention when executed by a computing device so that it carries out a method according to the second aspect of the invention. The features resulting from this and their advantages can be found in the descriptions of the first and second aspects of the invention, advantageous configurations of the first and second aspects of the invention being regarded as advantageous configurations of the third aspect of the invention and vice versa.

Further features of the invention emerge from the claims, the figures and the Figu renbeschreibung. The features and feature combinations mentioned above in the description, as well as the features and feature combinations mentioned below in the figure description and / or shown alone in the figures, can be used not only in the respectively specified combination, but also in other combinations, without the frame to leave the invention. Embodiments of the invention are thus also to be regarded as encompassed and disclosed, which are not explicitly shown and explained in the figures, but can be derived from the explained embodiments and can be generated by separated combinations of features. Versions and combinations of features are also to be regarded as disclosed, which thus do not have all of the features of an originally formulated independent claim. In addition, versions and combinations of features, in particular those explained above, are to be regarded as disclosed, which are based on the information provided in the back references of the Sayings combinations of features set out or differ from them. It shows:

Fig. 1 is a schematic and partially transparent perspective view of an inventive

 Layer construction device according to a first embodiment;

Figure 2 is a schematic perspective view of an introduction device and a Heizeinrich device, which are arranged on a support arm.

Fig. 3 is a schematic perspective view of the introduction device and flow guide device, which are arranged together on the support arm;

Fig. 4 is a schematic side sectional view of the layer construction device according to a further embodiment;

Fig. 5 is a schematic plan view of a variant of the layer construction device shown in Fig. 4;

Fig. 6 is a schematic perspective view, partly in section, of the layer construction device according to a further embodiment; and

7 shows a schematic view, partly in section, of the layer construction device according to the prior art for additive manufacturing of manufacturing products;

A layer construction device 10 shown schematically and partially in section in FIG. 7 is designed as a selective fiber sintering or fiber melting device according to the prior art and is explained below. To build an object or component 40, it contains a process chamber 20 with a chamber wall 42. In the process chamber 20, a construction container 44 with a wall 46 that is open at the top is arranged. A working level 48 is defined by the upper opening of the building container 44, the area of the working level 48 which lies within the opening and which can be used for the construction of the object 40, being referred to as construction field I. In the container 44 is movable in a vertical direction z rer carrier 50 is arranged, on which a base plate 52 is attached, which closes the building container 44 down and thus forms the bottom. The base plate 52 may be a plate formed separately from the carrier 50 and attached to the carrier 50, or it may be integrally formed with the carrier 50. Depending on the powder and process used, a construction platform 54 on which the object 40 is built can also be attached to the base plate 52. However, the object 40 can also be built on the base plate 52 itself, which then serves as the building platform 54. In FIG. 7, the object 40 to be formed in the building container 44 on the building platform 54 is shown below the working plane 48 in an intermediate state with a plurality of solidified layers, surrounded by material 56 that has remained unconsolidated and serves as the building material. The laser sintering device 10 further contains a storage container 58 for the powdery material 56 which can be solidified by electromagnetic radiation and a coater 60 movable in a horizontal direction Y for applying the material 56 to the construction field I. The storage container 58 can alternatively also below the level of the construction field I. be arranged (not shown). From this, the material 56 z. B. by a vertically movable in the z-direction metering die coater 60 are supplied. The laser sintering device 10 further includes an exposure device 64 with a laser 66, which generates a laser beam 68 as an energy beam, which is deflected via a deflection device 70 and through a locating device 72 via a coupling window 22, which is located on the top of the process chamber 20 in de Wall 42 is attached, is focused on the working plane 48.

Furthermore, the layer construction device 10 contains a control unit 74, via which the individual components of the device 10 are controlled in a coordinated manner for carrying out the construction process. The control unit 74 may include a CPU, the operation of which is controlled by a computer program (software). The computer program can be stored separately from the device on a storage medium from which it can be loaded into the device, in particular into the control unit 74. In operation, in order to apply a powder layer, the carrier 50 is first lowered by a height which speaks the desired layer thickness. A layer of the powdery material 56 is then applied by moving the coater 60 over the working plane 48. For safety, the coater 60 pushes a somewhat larger amount of material 56 in front of it than is required for the build-up of the layer. The coater 60 pushes the planned excess of material 56 into an overflow container 62. An overflow container 62 is arranged on both sides of the construction container 44. The powdery material 56 is applied at least over the entire cross section of the object 40 to be produced, preferably over the entire construction field I, that is to say the area of the working plane 48, which can be lowered by a vertical movement of the carrier 100. The cross section of the object 40 to be produced is then scanned by the laser beam 68 with a radiation exposure region (not shown) which schematically represents an intersection of the energy beam bundle with the working plane 48. As a result, the powdery material 56 is solidified at locations which correspond to the cross section of the object 40 to be produced. These steps are repeated until the object 40 is finished and can be removed from the building container 44. In order to generate a preferably laminar process gas flow in the process chamber 20, the laser sintering device 10 further contains a gas supply channel 34 ", a gas inlet nozzle 34 ', a gas outlet opening 30' and a gas discharge channel 30". The process gas flow moves horizontally across construction site I. A flow direction of the process gas stream in FIG. 7 runs in the same spatial direction as the coating direction Y, ie parallel to it. The gas supply channel 34 ", the gas inlet nozzle 34 ', the gas outlet opening 30' and the gas discharge channel 30" can, however, also be arranged, for example, rotated through 90 ° in or around the process chamber 20 such that the (horizontal) coating direction Y (corresponding to Rotated 90 °) is essentially perpendicular to the (horizontal) flow direction of the process gas stream. The gas supply and discharge can also be controlled by the control unit 74 (not shown). The gas sucked out of the process chamber 20 can be fed to a filter device (not shown), and the filtered gas can be fed back to the process chamber 20 via the gas feed channel 34 ″, whereby a circulating air system with a closed gas circuit is formed. Instead of only one gas inlet nozzle 34 ′ and one gas outlet opening 30 ′, a plurality of nozzles or openings can also be provided in each case.

1 shows a schematic and partially transparent perspective view of a layer construction device 10 according to the invention. The general structure and the general mode of operation of the layer construction device 10 are known from the description of the example shown in FIG. 7, but are varied in some aspects in the present case. FIG. 1 will be explained below in conjunction with FIG. 2 and FIG. 3, FIG. 2 showing a schematic perspective view of an introduction device 14 and a heating device 12, which are arranged on a common support arm 28a. Fig. 3 shows a schematic perspective view of a flow control device 16, which with its introduction device 14 together on a support arm 28a of a support Device 28 of the layer construction device 10 are arranged. The layer construction device 10, which in the present case is also designed as a selective laser sintering and / or laser melting device, serves for the additive production of the component 40 or at least one component region of this component 40 by means of an additive layer construction method. The component 40 or component area can be, for example, a component 40 of an aircraft engine or another turbomachine, whereby there are basically no restrictions on the type of construction and other component types can also be produced in the manner described below.

The layer construction device 10 comprises a housing 18, which limits a process chamber 20 be. On the top of the housing 18 there is a laser-transparent window 22, through which one or more fiber beams can enter the housing 18 for the selective solidification of a powder layer 24. Usually, the process chamber 20 has a relatively large internal height, which is primarily due to the requirements of the fiber optic unit. A fiber beam that emerges from an optics positioned centrally above construction site I hits the edge or eccentric areas of the construction and joining zone of construction site I the steeper the greater the distance between the level of construction site I and an exit point the assigned optics is. A steeper angle of incidence of the fiber beam generally standardizes the imaging properties, reduces the need for correction and thus promotes component precision. A large volume of the process chamber 20 is disadvantageous when it comes to keeping an atmosphere of the process chamber 20 and the elements contained therein. Therefore, a protective gas device (not shown) can be provided, by means of which protective gas or process gas, such as argon, can be passed into the process chamber 20 through a protective gas opening 34, for example, through the back of the housing 18 in order to define a defined gas atmosphere in the process chamber 20 to accomplish. However, for economic reasons, only a comparatively small volume flow of process gas is generally supplied.

The powder layer 24, which is also referred to as a powder bed, is applied with the aid of a powder feed, not shown here for reasons of clarity, via the coater 60 to the construction field I, which lies above the movable construction platform 54 (not shown) during operation of the layer construction device 10. The powder layer 24 is layer-by-layer and local in this build-up and joining zone by selective exposure to one or more fiber jets fused and / or sintered, whereby the component 40 or the component region is built up in layers according to a predetermined radiation strategy.

A particularly process-reliable additive production of component layers of a component of high quality is made possible in that the layer construction device 10 has the introduction device 14 already mentioned, by means of which an alternative or in addition to the “global” process gas flow through the process chamber 20 through the protective gas opening 34 “Local” protective gas flow, for example a gas flow essentially formed from argon, over which powder layer 24 can be generated, within which construction field I is located. In the exemplary embodiment shown here, the introduction device 14 is translationally movable above the powder layer and relative to the powder layer 24 in the x / y plane, that is to say in two mutually perpendicular spatial directions. For this purpose, it comprises an outlet opening 14a as an outlet opening, through which the protective gas flow exits essentially parallel to the powder layer 24 or to the level of the construction field I. The flow rate or the volume flow of protective gas can be varied as required. For example, a protective gas flow can be set in the range between 0.1 l / min and 20 l / min, for example 1 l / min, 5 l / min, 10 l / min or more. The protective gas is supplied via a flexible channel 36, which is led locally into the process chamber 20 via the outlet opening 14a of the introduction device 14 arranged at the end region of the channel. This local injection via the channel 36 can in principle take place from the same shielding gas reservoir as the global shielding gas loading or from a separate shielding gas reservoir with parameters (speed, volume flow, shielding gas composition, pressure difference to the environment etc.) that can be set independently of the global shielding gas loading. In relation to the volume of the process chamber 20, it is possible to remove contaminants from the atmosphere in a small-scale and targeted manner and to produce a locally improved protective gas atmosphere directly above the process site that is currently to be solidified.

The introduction device 14 is assigned a flow guide device 16 for guiding the protective gas stream over the powder layer 24. The flow guide device 16 generally forms a flow channel with a connection to the rest of the process chamber 20 that is as small as possible and thus effectively prevents the spread of contaminants occurring at the irradiation point (L, not shown in FIGS. 1 to 3) into the space of the process chamber 20. Instead, - the resulting impurities are removed in a targeted manner. For this purpose, the flow guide device 16 in the exemplary embodiment shown comprises two guide surface segments l6a,

16b, which act as longitudinal guide surfaces and form a flow channel which is open at the top and bottom (z direction), so that a (high) energy or laser beam 68 can be directed unhindered from above onto the powder layer 24 . The guide surface segments 16a, 16b have a length which corresponds at least substantially to the length of a construction site side S. In other words, the guide surface segments l6a, 16b extend over the entire construction site side S, so that in every possible x position of the energy beam a local protective gas stream can be passed over the powder layer 24 to remove impurities. Furthermore, the guide surface segments 16 a, 16 b are arranged at a distance (z direction) between 1 cm and 10 cm, for example at a distance of 1 cm, 2 cm, 3 cm, 4 cm, 5 cm or more, from the powder layer 24. It can be seen that the outlet opening 14a of the introduction device 14 in the exemplary embodiment shown is arranged within the flow channel formed or between end regions of the guide surface segments 16a, 16b. This overlap ensures that no negative pressure arises, through which z. B. powder could be sucked into the flow channel from behind, and that the inert gas flow cannot escape uncontrollably from the flow channel.

The flow guide device 16 defines an initial direction and a main flow direction H, indicated by two arrows, of the local flow of the shielding gas just above the x / y plane of the layer construction device 10, any orientations such as curved or curved designs of the flow guide device 16 being possible in principle . In general, the flow guiding device 16 should, if possible, be designed or arranged such that the protective gas flow does not stop during operation of the layer construction device 10 and is not swirled too strongly. By this comparatively simple measure, at least the radiation site as the working area of an energy beam on the construction site or exposure point with reference to a laser beam 68 as an energy beam is reliably kept clear by the directed protective gas flow of smoke, condensate, spratzem and other pollutants and harmful gases and the like.

The guide surface segment l6a is arranged in the present example on a support arm 28a of a Tragvor direction 28. As can be seen in Lig. 2, the heating device 12 and the Introducer 14 via respective support arms 28b, 28c held indirectly on the support arm 28a of the support device 28. Alternatively, it can also be provided that the heating device 12 and the introduction device 14 are held on a common support arm 28b or directly on the support arm 28a. The guide surface segments 16a, 16b are not shown in FIG. 2 for reasons of clarity. Alternatively, the heating device 12 and the introduction device 14 can be held and moved by means of individually or independently movable support arms, robot arms or the like. The heating device 12 is in turn presently designed as an inductive heating and comprises at least one induction coil 12a. Alternatively, two or more induction coils, for example a cross-coil arrangement, can also be provided. The introduction device 14 can also be fixed directly or indirectly on the support arm 28b of the heating device 12, so that the heating device 12, the introduction device 14 and the flow control device 16 can be moved together via the support device 28 relative to the powder layer 24. Alternatively, the carrying device 28 can comprise, for example, a robot arm or the like for positioning the heating device 12, the introducing device 14 and / or the flow guiding device 16. In a further embodiment, it can be provided that the induction coil 12a comprises holding elements (not shown), by means of which the flow guide device 16 or the guide surface segments 16a, 16b and / or the introduction device 14 are held on the induction coil 12a. For example, the guide surface segments 16a, 16b and / or the introduction device 14 can be held by means of a clip connection on the heating device 12, which permits particularly quick and easy assembly and disassembly.

The support arm 28a can be moved translationally along the powder layer 24 in the y-direction, while the support arm 28b, which is U-shaped in the present case, can be moved in the x-direction along the support arm 28a in order to position the induction coil 12a and certain areas of the powder layer 24 to heat a predetermined temperature. The laser beam or beams are then generally directed onto the pre-tempered area of the powder layer 24, which is below the induction coil 12a in the z direction, in order to selectively solidify it. It can be seen in particular in FIG. 2 that the outlet opening l4a is arranged in the z-direction approximately at the level of the induction coil l2a or just above the induction coil l2a, so that the protective gas flow in particular the area of the induction coil l2a which is particularly relevant for the component quality, in which the solidification of the powder takes place, contains impurities ff. The invention advantageously makes use of this comparatively small and slowly movable effective exposure area, namely an at least approximately rectangular field in this exemplary embodiment, the area of which is essentially limited by the inner circumference of the induction coil 12a arranged above it. A width of the flow channel formed by the flow guide device 16 or the guide surface segments 16a, 16b essentially corresponds to the width of the induction coil l2a, while the length of the flow channel essentially corresponds to the length of the construction site side S or, if appropriate, goes beyond it.

The guiding surface segments l6a, l6b flanking the induction coil l2a and the flow channel formed thereby extend in the exemplary embodiment shown in the same direction as a global flow over the construction site, since the flow channel or the protective gas flow bounded by him along the entire construction site I always in one Inlet opening as inlet opening of a gas outlet device 30 which extends in the present example along the entire assembly and joining zone I opens. The gas outlet device 30 additionally serves to extract or discharge the global protective gas flow introduced into the process chamber 20 through the protective gas opening 34. In other words, there is a local injection and a local (and global) extraction or discharge of protective gas at opposite ends of the flow channel formed by the flow guide 16. The inlet opening of the gas outlet device 30 can alternatively z. B. movable in a trained as a horizontal slot and provided with a guide rail outlet, so that local injection, flow channel and local suction coordinated, that is moved in the same direction and speed. In this way, an optimal flow profile can be permanently maintained. In addition, practically no disruptive influences from the outside are possible, so that overall a very effective removal of contaminants from the process chamber 20 can be achieved. Furthermore, it can in principle be provided that the gas outlet device 30 comprises one or more inlet opening (s) which extend over the entire length of the construction and joining zone I and through which suction is extracted or discharged during the entire layer construction process. A movement of the direction 16 and thus the flow channel is thus essentially limited by the extent of construction site I or the assembly and joining zone. Accordingly, the gas outlet device 30 preferably has an extension of at least the side length of the rectangular construction field or the assembly and joining zone I in the y direction. Alternatively, it can be provided that an inlet opening of the gas outlet device 30 is moved together with the heating device 12, the inlet device 14 and / or the flow guide device 16 along the assembly and joining zone I (for example in the y direction), so that the outlet opening 14a of the introduction device 14 is always directed towards the inlet opening of the gas outlet device 30 and the protective gas flow is guided over the pul layer 24 at least essentially without deflection and thus with little swirling, while adjacent and currently unprocessed areas of the powder layer 24 are not vented. For this purpose, the gas outlet device 30 can comprise, for example, a plurality of openable and closable flaps, flow guide elements or the like, which are opened or closed or adjusted as a function of a relative position of the introduction device 14. It is also possible that the gas outlet device 30 comprises a type of blind which selectively opens an inlet opening which can be moved along the gas outlet device 30 depending on the position of the inlet device 14. The control or regulation of the individual components of the layer construction device 10 can be carried out, for example, via a control and / or regulating device (not shown) which executes a corresponding program code. For this purpose, the program code can be provided by means of a storage medium and processed by a processor of the control and / or regulating device.

As can be seen in particular in FIGS. 1 and 3, the longitudinal guide surface segments 16a, 16b form a type of “guide trough” which extends in the z direction from a height just above the construction field or the powder layer 24 to a height Extend over the outlet opening 14a of the local introduction device 14. For example, the guide surface segments 16a, 16b or their highest point P _| , (see FIG. 4) with respect to the powder layer 24 in the z direction extend 1 cm, 2 cm, 5 cm or higher over the outlet opening 14a. In addition to an advantageous flow of the protective gas, this also enables a relatively flat angle of incidence of a solidifying energy beam (laser / electron beam). Optionally, the guide surface segments 16a, 16b can only be partially closed off at the side or have a perforated design. This means that less gas volume is moved in the process chamber 20 in the y direction when the induction coil 12a and the flow guide device 16 are moved. This can reduce disadvantageous turbulence, which could otherwise lead to powder blowing on site I. This beneficial effect can be enhanced if the upright or vertical (ie in z- Direction) arranged guide surface segments l6a, 16b have a height that does not go beyond the absolutely necessary dimension for flow guidance in the x direction. According to a further embodiment variant, a region of the guide surface segments 16a, 16b, which in operation lies in the z direction above the outlet opening 14a of the inlet device 14 or above the inlet opening of the gas outlet device 30, can be arranged at a flatter angle to the construction site I than their area below. In other words, the guide surface segments l6a, 16b can be angled or curved in profile, with a cross section of the flow channel widening in a direction facing away from the construction site I (ie in the z direction towards the window 22). This constructive solution can be particularly advantageous when using an optional ceiling inflow of process gas, since the resulting trich effect effects gas flowing in from above into the guide trough or the flow channel or possibly bundles it slightly without disturbing the local flow in the flow channel.

In the case of the described local flow of the construction field I, the flow target area can vary locally. In order to keep the process zone and the impact surface of an energy beam L as effective as possible and for the fastest possible removal of impurities in the gas atmosphere, the flow channel formed by the guide surface segments l6a, 16b of the flow guide device 16 for guiding the gas inflow from the introduction device 14 together with the flow target area or following a process point at which the powder bed 24 is selectively solidified or is to be moved. The only locally acting gas flow led from the outlet opening l4a and the flow channel formed by the flow guide device 16 can be moved together by a single drive or separately by two drives, the two drives being able to be moved mechanically completely or to a limited extent independently of one another. This generally represents a separate aspect of the invention, which in particular is not limited to a specific main flow direction H of the protective gas stream. For example, as shown in FIG. 1, a first support arm 28a can be moved in a first spatial direction (y as an example here) and a second support arm 28b can be carried along on the first support arm 28a, and independently of the first support arm 28a in a second Spatial direction (here x as an example) can be moved or moved. Alternatively, however, combinations or alternative variants of the translational and / or rotatory movability of the individual support arms 28a, 28b are also possible. For example, the first support arm 28a can be movable in exactly one first spatial direction (y direction) and the second support arm 28b can be movable in the first spatial direction (y direction) and in a second spatial direction (x direction), the second spatial direction (x direction) preferably being perpendicular to the first spatial direction (y direction). As an alternative or in addition, at least one support arm 28a, 28b can be movable within a plane lying parallel above construction field I. A separate drive means of the support device 28 for moving can generally be assigned to each support arm 28a, 28b. Alternatively, it can be provided that at least two support arms 28a, 28b can be moved by means of a common drive means of the support device 28.

In general, the movability of the heating device 12 and / or the introducing device 14 and / or the flow guiding device 16 can, for. B. in a plane parallel to site I and optional also take place in the z direction. For example, at least one robot arm (not shown) can be used, which allows free translational and / or rotational mobility in the x-y plane and, if appropriate, mobility in the z direction. However, alternative support devices 28 are also conceivable instead of a robot arm.

Preferably, a drive of the heating device 12, which is often required anyway, is also used synergistically for driving the flow guide device 16 and / or the introduction device 14. This is advisable since a heating area of the heating device 12 and a flow target area of the flow guiding device 16 and / or the introducing device 14 can form an intersection or at least adjoin one another, wherein a vertical distance is as small as possible, for example towards zero. A position or movement of the heating device 12 and the heating region generated by it thus determines a position or movement of the flow target area defined by the flow guide device 16 and / or the introduction device 14. The position or movement of the heating device 12 and / or the flow guiding device 16 and / or the introducing device 14 is preferably controlled or regulated in such a way that the flow target area and the heating area form the greatest possible intersection with one another in an orthogonal projection onto the level of the construction field, especially preferred are essentially identical.

If, for example, a so-called “cross-coil” is used as the heating device 12, which comprises two inductors that can be moved relative to one another in order to be able to overlay the individual induction fields, the introduction device 14 requires an egg for the local gas inlet. gene drive or support arm or at least must be movable such that it can be moved or moved with the overlapping area of the two inductors, that is to say the most intensive heating area of the heater 12.

In a further aspect of the invention, which is independent of the other aspects of the invention, the heating device 12, as shown for example in FIG. 5 or 6, has a larger inductor or a large induction coil l2a and a smaller inductor or a small induction coil l2b , wherein the small induction coil l2b - preferably exclusively - within the large induction coil l2a or above the projection surface of the large induction coil l2a on the construction area I can be moved or moved. In this embodiment of the heating device 12, it can then be provided that the introducing device 14 and / or the flow guiding device 16 are fastened to the induction coils l2a, l2b or respectively to an induction coil l2a, l2b or jointly to the respective support arm 28a, 28b or at least can be moved together with the respectively assigned induction coil l2a, l2b. A method with the induction coils l2a, l2b advantageously fulfills the above-defined goals of the guided flow depending on the heating area without restrictions.

Another independent idea of the invention is in a coupling of the mobility of the flow guide device 16 and / or the introduction device 14 to a selected operating mode of the flow and / or the heating. This can be controlled or regulated, for example, with the aid of a correspondingly designed control device or control unit 74 of the layer construction device 10. For example, a first, “active” operating position can be provided, in which the local gas inflow and the conduction of the local gas flow take place, as shown, for example, in FIG. 1. This operating position of the heating device 12 and the flow guiding device 16 and / or the introducing device 14 above Construction site I is suitable for heating or flow and can provide mobility in all degrees of freedom or restricted to degrees of freedom appropriate for the respective application. In contrast, in a second, "inactive" operating position there is no local gas inflow or local conduction Gas flow. This operating position preferably comprises moving the flow guiding device 16 and / or the introducing device 14 into an area outside the traversing movement of the coater 60, in order not to prevent the application of a new powder layer. For example, a method of the heating device 12 and / or the flow Mungsleiteinrichtung 16 and / or the introducer 14 in a lateral parking position and / or moving or pivoting upward (z-direction) in the free space of the process chamber 20 may be provided. The “inactive” operating position can also be selected, for example, during the set-up, cleaning, flooding, etc. of the layer construction device 10 or during non-process times. This control or regulation of the operating positions of the heating device 12 and / or the flow control device 16 and / or the introduction device 14 generally represents a separate aspect of the invention that can be implemented independently of the other aspects of the invention.

FIG. 4 shows a schematic side sectional view of the layer construction device 10 according to a further exemplary embodiment and will be explained in the following in conjunction with FIG. 5. 5 shows a schematic plan view of a variant of the layer construction device 10. The basic structure of the layer construction device 10 corresponds to that of the exemplary embodiment shown in FIG. 1. In contrast to this exemplary embodiment, the flow guide device 16 is designed to be telescopic and comprises — in number and arrangement as an example — three guide surface segments te l6a-c that can be displaced in the X direction. It can be seen that for this purpose the guide surface segments l6a-c are mounted on the first support arm 28a via individual support arms 28c-28e and can be moved relative to the construction field I as a function of the x position of the introduction device 14. 4 also shows that the main flow direction H of the protective gas or process gas stream flowing out of the outlet opening l4a is not aligned exactly parallel to the powder layer 24, but at a flat angle of approximately 20 ° to the level of the construction site I, that is to say easily directed onto the powder layer 24, emerges from the outlet opening 14a of the channel 36 or its introduction device 14. Due to the comparatively large distance from the outlet opening 14a to the gas outlet device 30, through which the local shielding gas stream is again discharged or sucked out of the process chamber 20, the shielding gas stream widens after leaving the outlet opening 14a and becomes upward, that is to say deflected away from the powder layer 24 in the z direction. The limits of the expanding protective gas flow are represented by the reference symbol IV. The angle of the main flow direction H in the direction of the powder layer 24 is selected as a function of the flow velocity and / or the distance to the gas outlet device 30 such that the protective gas flow does not expand substantially in the z direction via the gas outlet device 30, but at most up to upper edge of the suction opening of the gas outlet device 30. 4 that the guide surface segments l6a-c are of different sizes, the guide surface segment l6a closest to the outlet opening l4a being lowest in the z direction and the most distant guide surface segment l6c being highest in the z direction. This ensures that a highest point P _| , the flow control device 16 lies not only in the z direction above the outlet opening 14a, but also above the maximum widened protective gas flow (IV). Furthermore, it can be seen that, based on the construction site I, a deepest point P _{n of} all the guide surface segments 16a-c is arranged closer to the pul layer 24 than a deepest point or the lower edge of the outlet opening 14a of the channel 36 Flow guidance guaranteed.

In contrast to the exemplary embodiment shown in FIG. 4, the heating device 12 in FIG. 5 comprises a large induction coil l2a and a small induction coil l2b which can be moved within the large induction coil l2a and whose fields can be deliberately superimposed for preheating the powder layer 24, to generate particularly high temperatures. 4 and 5, the impact surface L of an energy beam, for example a laser beam on the powder layer 24 is shown as an example, which lies regularly within the large and the small induction coil l2a, l2b construction field I. In particular, FIG. 5 also shows the importance of the flow guide device 16, which is open at least in the working area of the laser upwards (ie towards the housing ceiling of the process chamber 20) and downwards (ie towards the construction field I), thereby ensuring that the laser beam 68 is unhindered the lenster 22 in the process chamber ceiling can be directed onto the tempered powder layer 24 in order to selectively solidify it.

Fig. 6 shows a schematic perspective view, in parts sectional view, of the layer construction device 10 according to a further embodiment. In contrast to the previous example, the flow guide device 16 comprises three guide surface segments 16a-c, which are different in size, shape and arrangement. Of this, the guide surface segment 16b is designed as a horizontal cover surface, which at least partially closes off the flow guide device 16 during operation. This can prevent the shielding gas stream guided from the channel 36 and the introduction device 14 into the process chamber 20 from widening too much and always being reliably directed in the direction of the gas outlet device 30. The guide surface segment 16b is slidably mounted on a vertical guide in the z direction. Preferably a position of the guide surface segment 16b in the z direction, ie its respective distance from the construction field I, is set as a function of a current distance of the introduction device 14 or the outlet opening 14a from the inlet opening of the gas outlet device 30 (in the x direction). For example, at a short distance of the outlet opening 14a from the inlet opening of the gas outlet device 30, a low position of the guide surface segment 16b can be chosen, since the flow cone (identified by the reference symbol IV in FIG. 4) of the local process gas flow only widens to a small extent before it reaches the inlet opening of the gas outlet device 30, and thus essentially only flows along the underside of the guide surface segment 16b. In contrast, when the outlet opening 14a is at a large distance from the inlet opening of the gas outlet device 30, a high position of the guide surface segment 16b can be selected. The guide surface segment l6c is arranged below the introduction device 14 and ensures that the protective gas flow is limited in some areas downwards and flows over the small induction coil l2b. This on the one hand prevents the powder layer 24 from being whirled up, and on the other hand ensures particularly reliable removal of impurities occurring in the region of the small induction coil 12b.

The configuration of the flow guiding device 16 can be varied as required, it should only be ensured that a largely trouble-free consolidation of the powder layer 24 remains possible. For this purpose, it can be provided in a further embodiment of the invention that the flow guiding device 16 consists entirely or partially of a (highly) energy-beam-transparent material, so that partially or completely closed flow channels can also be realized, through which the energy jet nevertheless solidifies onto the Powder layer 24 can be passed.

As a further alternative, the flow guide device 16 can be formed in one piece and extend as a rudiment only in regions between the introduction or introduction device 14 and the gas outlet device 30, in order for the flow guide device 16 to collide with other components when the small induction coil l2b is relative to the large induction coil l2a exclude in the process chamber 20. The introduction device 14 can be fixed to a wall of the flow guide device 16, while the flow guide device 16 in turn can be fixed on the support arm 28 via the induction coil l2b. The inlet device 14, the flow guide device 16 and the induction coil 12b can thus be on the one hand always moved together relative to the induction coil l2a in the x direction and on the other hand together with the induction coil l2a in the y direction over the powder layer 24. This embodiment also offers the advantage that at least the exposure point is reliably kept clear by a directed flow of smoke / condensate / spratzem etc. and that the initial guiding effect of the flow guiding device 16 is ensured on both sides, so that alignment is also ensured in this case of the protective gas flow from the outlet opening 14a to an inlet opening of the gas outlet device 30.

In order to avoid undesirable heating, the flow guide device 16 can generally preferably be made of a non-metallic or non-electrically conductive and temperature-stable material such as polyether ether ketone (PEEK), so that the flow guide device 16 does not itself heat up inductively on the one hand and the one during solidification on the other hand the powder layer 24 withstands temperatures arising without damage.

In summary, the layer construction device 10 according to the invention and in particular the flow guide device 16 according to the invention enables different degrees of delimitation of a flow channel by one or more guide surface segments 16a-c. The flow guide device 16 can in principle conduct the inert gas flow only in one direction. Alternatively, the flow guide device 16 can form a type of guide groove, as was shown above by the two longitudinal guide surface segments 16a, 16b, which extend in the z direction from a height just above the powder bed 24 to a height just above an outlet of the local injection extend (e.g. 1, 2, 3, 4, 5 cm or more above). The flow guide device 16 and thus the guide channel formed thereby preferably extends at least substantially along an induction coil 12a or along an entire construction site side S.

This enables a relatively flat angle of incidence of a solidifying energy beam (laser / electron beam). A partially closed design also has advantages when using a possibly bundled global inert gas inflow, since a funnel effect can be realized that directs the inflowing gas into the guide trough or possibly bundles it slightly. The local protective gas flow in the flow channel formed by the flow guide device 16 is not disturbed. In addition, less gas volume is moved in the process chamber 20 when the flow guide device 16 is moved when the upright ones Guide surface segments l6a-c are dimensioned comparatively flat. This also reduces disadvantageous turbulence, which could possibly lead to powder blowing on site I.

As an alternative, the flow guide device 16 can in principle form a tunnel, which is closed at the top or in its entirety, with a large-area, preferably all-round delimitation of the flow channel by guide surface segments 16a-c. In this case, the flow guiding device 16 can have one or more recesses or cutouts or regions on the upper side (“windows”) that are transparent to high-energy beams, so that one or more (high) energy or laser beams can strike the construction field unhindered in this case a position of the recess or recess is fixed relative to the position of a small induction coil l2b above the assembly and joining zone I. However, an extension or geometry of the recess or recess can also be of variable design Defined flow of the protective gas flow possible, which ensures a particularly effective removal of contaminants.

The parameter values specified in the documents for the definition of process and measurement conditions for the characterization of specific properties of the subject matter of the invention are also to be considered within the scope of deviations - for example, due to measurement errors, system errors, DIN tolerances and the like - as included in the scope of the invention hen.

Reference symbol list:

10 layer construction device

12 heating device

l2a induction coil

l2b induction coil

 14 introduction device

l4a outlet opening

 16 Flow control device 16a guide surface segment

 16b guide surface segment l6c guide surface segment

 18 housing

 20 process chamber

 22 coupling window

 24 powder bed

 28 carrying device

 28a support arm

 28b support arm

 28c support arm

 30, 30 ', 30 "gas outlet device 34, 34', 34" gas supply channel 36 channel

 40 component

 42 chamber wall

 44 building containers

 46 wall

 48 working level

 50 carriers

 52 base plate

 54 construction platform

56 material 58 storage containers

 60 coaters

 62 overflow tank

 64 exposure device

 66 lasers

 68 laser beam

 70 deflection device

 72 focusing device

 74 control unit

 I construction site

 IV limits of expansion of a gas flow x, y horizontal direction

z vertical direction

 L impact surface of an energy beam

 S site side

 H main flow direction

 Ph Highest point of the flow control device

Pn Lowest point of the flow control device

Claims

claims 1. Layer construction device (10) for the additive production of at least one component area of a component (40) by an additive layer construction method, comprising a process chamber (20), within which at least:  a construction field (I) for building up the component area in layers from a material (56);  at least one flow guide device (16) which comprises at least one channel (36) with an outlet opening (14a) for introducing a protective gas into the process chamber (20); and  a gas outlet device (30) which is stationary with respect to the construction field (I) for removing the protective gas from the process chamber (20)  are arranged  characterized in that  the flow guide device (16) is designed to arrange an end region of the duct (36) of the flow guide device (16) of the flow guide device (16) above a level of the construction field (I) and the type relative to the level during operation of the layer construction device (10) of the construction site (I) so that at least a predominant part of the protective gas can be conducted locally over a partial region of the construction site (I) along a main flow direction (H) which is at least substantially parallel to the plane of the construction site (I). 2. layer construction device (10) according to claim 1,  characterized in that  the flow guide device (16) comprises at least one guide surface segment (16a-c) for limiting the spreading of the protective gas introduced into the process chamber (20). 3. layer construction device (10) according to claim 2,  characterized in that the at least one guide surface segment (16a-c) has a longitudinal extent of at least 50%, preferably at least 70% and particularly preferably at least 100% of a construction site side (S) and / or a construction site diameter of the construction site (I) and / or that the at least one guide surface segment (16a-c) and the outlet opening End region (14a) of the channel (36) of the flow guide device (16) can be moved relative to one another. 4. layer construction device (10) according to claim 2 or 3,  characterized in that  the flow guide device (16) comprises at least two guide surface segments (16a-c) which are arranged opposite one another and / or which limit an outlet opening (14a) of the channel (36) of the flow guide device for the protective gas in relation to the construction site (I) and / or which are arranged to be fixed relative to one another or movable relative to one another. 5. layer construction device (10) according to one of claims 2 to 4,  characterized in that at least one guide surface segment (16a-c) is arranged at an angle between 60 ° and 120 ° to the construction field (I) and / or that, based on the construction field (I), a highest point (P _h ) of at least one guide surface segment (16a-c) in the operation of the stratification device (10) has a greater distance from the construction site (I) than a highest point of an outlet opening (l4a) of the channel (36) of the flow control device (16) and / or that a lowest point in relation to the construction site (I) (P _n ) at least one guide surface segment (16a-c) in the operation of the layer construction device (10) is closer to the construction field (I) than a lowest point of an outlet opening (14a) of the channel (36) of the flow control device (16). 6. layer construction device (10) according to one of claims 2 to 5,  characterized in that at least one guide surface segment (16b) of the flow guide device (16) forms a top side in relation to the construction field (I) and / or that at least one guide surface segment (16c) of the flow guide device (16) forms a bottom side in relation to the construction field (I) and / or that at least one guide surface segment (16b) of the flow guide device (16) opens a passage opening for an energy beam (68) at least during operation of the layer construction device (10). 7. layer construction device (10) according to one of claims 1 to 6,  characterized in that  a position of the flow guide device (16) within the process chamber (20) relative to the construction field (I) can be set as a function of a position of an impact surface (L) of an energy beam on the construction field (I) and / or that the flow guide device (16) at least can be moved essentially simultaneously with the impact surface (L) of the energy beam on the construction site (I) relative to the construction site (I). 8. layer construction device (10) according to one of claims 1 to 7,  characterized in that  at least one guide surface segment (16a-c) has a changeable geometry and / or that at least one longitudinal extent of the flow guide device (16) can be set. 9. layer construction device (10) according to one of claims 1 to 8,  characterized in that  this comprises a further flow guide device in the area of an upper side of the process chamber (20), by means of which a global protective gas flow with an essentially perpendicular main flow direction can be generated in relation to the construction field (I). 10. layer construction device (10) according to one of claims 1 to 9,  characterized in that  A support device (28) is provided, by means of which at least the end region of the channel (36) of the flow guide device (16) comprising the outlet opening (14a) and / or at least one guide surface segment (16a-c) in at least one spatial direction relative to the construction field ( I) is movable within the process chamber (20). 11. layer construction device (10) according to claim 10,  characterized in that the carrying device has at least two supporting arms, each movable relative to the construction site (28a, 28b), the first support arm (28a) preferably being movable in exactly one first spatial direction and the second support arm (28b) being movable in the first spatial direction and in a second spatial direction, the second spatial direction being perpendicular to the first spatial direction is. 12. layer construction device (10) according to one of claims 1 to 11,  characterized in that  this comprises a heating device (12) by means of which the construction field (I) can be tempered at least in some areas. 13. layer construction device (10) according to one of claims 1 to 12,  characterized in that  the outlet opening (14a) of the channel (36) and / or at least one inlet opening of the gas outlet device (30) is arranged closer to the construction field (I) than to a process chamber ceiling during operation of the layer construction device (10). 14. A method for operating a layer construction device (10) according to one of claims 1 to 13, in which before, during and / or after an additive production of at least one component area of a component (40) by an additive layer construction method by means of the flow control device (16) End region of the channel (36) of the flow guide device (16) comprising the outlet opening (l4a) is arranged above the plane of the construction field (I) and is moved relative to the plane of the construction field (I) in such a way that at least a predominant part of the outlet opening (l4a) escaping protective gas is passed locally along a main flow direction (H), which is at least substantially parallel to the level of the construction field (I), over a partial region of the construction field (I). 15. Storage medium with a program code that is designed to run when off  to control a layer construction device (10) according to one of claims 1 to 13 by means of a computing device in such a way that it carries out a method according to claim 14.