Manufacturing device for additive manufacturing of components from powder materials, method for changing the beam distribution of an energy beam, and use of at least one acousto-optical deflector

Abstract

The present invention relates to a manufacturing device (1) for additive manufacturing of components from powder materials, having: a beam generation device (3) configured to generate an energy beam (5); a scanning device (7) configured to displace the energy beam (5) to a plurality of irradiation positions (11) within a working area (9) in order to manufacture a component from powder materials arranged in the working area (9) by means of the energy beam (5); a deflection device (13) configured to displace the energy beam (5) to a plurality of beam positions (17) at one of the plurality of irradiation positions (11) within a beam area (15), and a control device (19) operatively connected to the deflection device (13) and configured to control the deflection device (13) and to change the beam distribution in the beam area during component manufacturing by changing the control of the deflection device (13).

Description

Field of the Invention

[0001] The present invention relates to a manufacturing apparatus for additive manufacturing of components from powder materials, a method for changing the beam profile of an energy beam, and the use of at least one acousto-optic deflector. Background Art

[0002] In the process of additive manufacturing of components from powder materials, an energy beam is typically displaced to a predetermined irradiation position in the working area, in particular along a predetermined irradiation path, to locally solidify the powder material arranged in the working area. This is particularly repeated layer by layer in the powder material layers successively arranged in the working area, in order to ultimately obtain a three-dimensional component made of solidified powder material. In order to increase productivity and / or to locally design the material properties of the produced component differently, it is desirable to expose different regions within the component to be manufactured, in particular different regions within the same powder material layer in the working area, to different beam profiles of the energy beam. Generating a suitable, adapted beam profile by means of conventional beam shaping, in particular by refractive or interference optical elements in the case of an optical energy beam, is often complex and not flexibly utilisable. In particular, it has proven difficult or even almost impossible to switch between different beam profiles during an individual production process, in particular within a powder material layer. In addition, conventional beam shaping methods only allow a limited selection of beam profiles to be achieved, so that the applicability of said beam profiles is also limited. Summary of the Invention

[0003] The object of the present invention is to provide a manufacturing apparatus for additive manufacturing of components from powder materials, a method for changing the beam profile of an energy beam on the working area of such a manufacturing apparatus, and the use of at least one acousto-optic deflector, wherein at least the disadvantages are reduced, preferably avoided.

[0004] This object is achieved by providing the technical teaching of the present technology, in particular the teaching of the independent claims and the technical teaching of the embodiments disclosed in the dependent claims and the description.

[0005] This task is solved in particular by providing a manufacturing device for additive manufacturing of components from powder materials, which has a beam generation device configured to generate an energy beam. The manufacturing device also has a scanning device configured to displace the energy beam to a plurality of irradiation positions within a working area in order to manufacture a component from the powder materials arranged in the working area by means of the energy beam. Furthermore, the manufacturing device has a deflection device configured to displace the energy beam to a plurality of beam positions at one of the plurality of irradiation positions within a beam area. In addition, the manufacturing device has a control device which is operatively connected to the deflection device and is configured to control the deflection device and to change the beam distribution in the beam area during component manufacturing by changing the control of the deflection device.

[0006] In this way, in particular, the beam distribution to be used can be predetermined and easily and quickly changed during component manufacturing, especially during processing of the same powder material layer, without the need for a specific device dedicated especially to generating the beam distribution. In particular, it is possible to easily and quickly switch between different beam distributions. Thus, the manufacturing device is able to very flexibly generate a suitable beam distribution in a manner adapted to the locally prevailing requirements and / or conditions in each case, especially to the area of the component to be manufactured in each case. Therefore, the manufacturing device is not only highly productive but also enables adjustment of local changes in the material properties of the components produced. Due to this, in particular, the quality of the components produced by the manufacturing device proposed here can be improved, especially by selecting a particularly suitable beam distribution. Since there is no need for interference optical elements specifically adapted to the beam distribution, especially no refractive optical elements or static interference optical elements, the manufacturing device is designed to be cost-effective despite its high degree of flexibility in applicability, especially with regard to the aspect that different types of devices are not required for generating different beam distributions, which would cause additional component costs and would possibly require laborious and time-consuming switching between the devices. The manufacturing device proposed here also allows switching between the most efficient, especially also fast, component manufacturing and particularly high-quality manufacturing by appropriately controlling the scanning device and thus also the deflection device, especially also for adjusting local changes in the material properties of the components produced, for example, a greater hardness in the area of the component surface than inside the component.

[0007] On the one hand, the scanning device and on the other hand the deflection device in particular allow separating the time scalar and the length scalar associated with the production of the component to be produced. The scanning device is configured to displace the energy beam almost integrally along a plurality of irradiation positions, in particular along a predetermined irradiation path, over the entire working area within a longer time scalar compared to the deflection device, while the deflection device is configured to displace the energy beam almost locally to a plurality of beam positions within the beam area at the irradiation position within a shorter time scalar relative to the time scalar of the scanning device, the irradiation position being quasi-static due to the time scalar separation and the irradiation position being predetermined by the scanning device. Due to the time scalar separation, the specific beam distribution of the beam area, both as a geometry and as an intensity distribution, thus appears almost statically at almost each of the plurality of irradiation positions. The beam distribution generated in this way is in particular then displaced by the scanning device along the plurality of irradiation positions, in particular along the irradiation path. By changing the control of the deflection device, it is now possible to advantageously change the beam distribution of the beam area almost as desired, that is to say, in particular change the shape of the beam area and / or the intensity distribution in the beam area, and even between irradiation positions if necessary. However, generally, a plurality of adjacent irradiation positions, in particular consecutive sections of the irradiation path in each case, are swept by the same beam distribution. However, different sections of the irradiation path are preferably swept by different beam distributions.

[0008] The generated beam distribution is also quasi-static in particular with respect to the melting process of the powder material, and the time scalar for the deflection device to deflect the energy beam is significantly shorter than the characteristic interaction time between the energy beam and the powder material. Averaged over time, the dynamically generated beam distribution thus interacts with the powder material like a statically generated distribution.

[0009] An additively manufactured component is in particular to be understood as a component constructed layer by layer from powder material, in particular a powder bed-based method for manufacturing a component in a powder bed, in particular the following manufacturing methods, which are selected from the group of the following methods: selective laser sintering, laser metal fusion (LMF), direct metal laser melting (DMLM), laser net shape manufacturing (LNMS), and laser engineered net shaping (LENS). Thus, the manufacturing device is configured to in particular implement at least one of the above-mentioned additive manufacturing methods.

[0010] An energy beam is generally understood to be a directional radiation capable of transmitting energy. Generally, the directional radiation can be particle radiation or wave radiation. The energy beam propagates through physical space along a propagation direction and, in the process, transmits energy along its propagation direction. In particular, local deposition of energy in the working area can be achieved by means of the energy beam.

[0011] In a preferred design, the energy beam is the working beam. The working beam is in particular understood as directed, continuous or pulsed electromagnetic radiation which, with respect to its wavelength or wavelength range, is suitable for the additive manufacturing of components from powder materials, in particular for sintering or melting powder materials. The working beam is in particular understood as a laser beam which can be generated continuously or in pulsed fashion. The working beam preferably has a wavelength or wavelength range within the visible electromagnetic spectrum, or within the infrared electromagnetic spectrum, or within the overlap range between the infrared and visible ranges of the electromagnetic spectrum.

[0012] The working area is in particular understood as an area, in particular a plane or surface, in which the powder material is arranged and which is locally irradiated by the energy beam in order to locally solidify the powder material. The powder materials are in particular arranged layer by layer in the working area and are locally applied by the energy beam in order to manufacture the component layer by layer.

[0013] The irradiation position is in particular understood as a location within the working area at which energy is locally deposited into the working area by means of the energy beam, in particular into the powder material arranged there. The scanning device is preferably provided for shifting the energy beam along an irradiation path within the working area, where the irradiation path consists of a time sequence of irradiation positions successively traversed by the energy beam. In this case, the individual irradiation positions can be arranged at a distance from one another or can otherwise overlap. The irradiation path can in particular be a path continuously scanned by the energy beam.

[0014] The beam area is in particular understood here as the area at the irradiation position within which a specific intensity distribution is generated. The beam area in particular has a planar extent which is greater than the cross-section of the energy beam projected onto the working area.

[0015] Accordingly, the deflection device is in particular provided for shifting the energy beam to a fixed irradiation position within the beam area, in particular at each irradiation position, thereby irradiating the energy beam to a fixed irradiation position within the working area, to a specific area (beam area) which is greater than the cross-section of the energy beam projected onto the working area; in contrast, the scanning device is provided for shifting the energy beam between the individual irradiation positions, thereby in turn enabling the deflection device to move the energy beam past different locations of a new beam area. Accordingly, the deflection device is used for the local deflection of the energy beam at the irradiation position, while the scanning device is used for the overall displacement of the energy beam within the working area.

[0016] Accordingly, the scanning device and the deflection device differ in particular in terms of a possible displacement length scale as implemented, wherein the scanning device is preferably arranged to move the energy beam over the entire working area, and wherein the deflection device is arranged to locally deflect the energy beam within the beam area at the irradiation positions predetermined by the scanning device, and the corresponding beam area is much smaller than the working area. In particular, the beam area preferably has a length scale in the range of a few (i.e., less than ten) millimeters to a few centimeters, preferably has a planar extent in the range of a few square millimeters to a few square centimeters, while the working area has a length scale in the range of a few decimeters to a few meters, preferably a planar extent in the range of a few square decimeters to a few square meters.

[0017] On the one hand, the scanning device and on the other hand the deflection device preferably also differ in terms of the time scale at which the deflection of the energy beam occurs: The deflection of the energy beam within the beam area by the deflection device preferably takes place on a shorter time scale, in particular a much shorter time scale, than the deflection of the energy beam by the scanning device within the working area, i.e., than the change from one irradiation position to the next. In this way, it is advantageously possible to appropriately shift the energy beam within the beam area to each irradiation position predetermined by the instantaneous setting of the scanning device by means of the deflection device, and a specific beam distribution can be generated quasi-statically. The time scale at which the deflection device can deflect the energy beam is preferably 10 to 1000 times smaller, preferably 20 to 200 times smaller, preferably 40 to 100 times smaller or more than the time scale at which the scanning device deflects the energy beam.

[0018] The control device is preferably selected from the group comprising: a computer, in particular a personal computer (PC), a plug-in card or a control card, and an FPGA board. In a preferred design, the control device is an RTC6 control card from SCANLAB GmbH, in particular the currently configured control card available at the priority date of this property right.

[0019] The control device is preferably arranged to synchronize the scanning device and the deflection device by means of a digital RF synthesizer, wherein the RF synthesizer is controlled via a programmable FPGA board. Additionally, preferably, the relatively slow movement of the scanning device and the fast movement of the deflection device are separated by means of a frequency divider. Preferably, the position values of the beam distribution and the predetermined values are calculated and then converted into time-synchronized frequency indices of the RF synthesizer in the FPGA board. Before doing so, it is necessary to spatially allocate the beam distribution to the irradiation positions in the respective powder material layer, which is preferably already implemented in the build processor. The build processor writes the corresponding data to a file, which is then preferably used by the control device. Alternatively or additionally, it is preferably possible to select from a predetermined beam distribution.

[0020] A further aspect of the invention provides that the deflection device is arranged to shift the energy beam in jumps to a plurality of beam positions, where the plurality of beam positions are discrete beam positions. Adjacent beam positions can in particular be spaced apart from one another. However, adjacent beam positions can also at least regionally overlap one another. The energy beam is advantageously not shifted continuously between the beam positions by the deflection device, but rather in particular in discrete steps. Without loss of generality and without wishing to be bound by theory, for all practical purposes, it can be assumed that in the case of a sudden or discrete shift from a first beam position to a second beam position, the energy beam almost disappears at the first beam position and appears at the second beam position, without in particular sweeping through the intermediate region. In this way, the energy beam can be shifted very quickly within the beam region, and material transport processes that would otherwise be based on the continuous shift of the energy beam can preferably be avoided, which improves the quality of the produced component.

[0021] A further aspect of the invention provides that the control device is arranged to change the shape of the beam region, which is the beam profile, during the production of the component. The shape of the beam region should in particular be understood here as the geometry of the outer boundary of the beam region, or equivalently as the shape of the surface that the energy beam quasi-statically sweeps through within the beam region. This corresponds to the quasi-static cross-sectional distribution of the energy radiation with which the corresponding irradiation positions of the working region are irradiated.

[0022] Alternatively or additionally, the control device is preferably arranged to change the intensity distribution within the beam region, which is the beam profile, during the production of the component. The intensity distribution should in particular be understood here as the surface power density distribution of the energy beam.

[0023] By changing the beam profile, in particular the shape and / or intensity distribution of the beam region, the beam profile can advantageously be easily and quickly adapted as required during the production of the component.

[0024] A further aspect of the invention provides that the control device is arranged to predetermine the beam profile, in particular the shape of the beam region, as a function of the instantaneous irradiation position within the component to be produced, in particular within the same powder material layer. The control device is in particular arranged to predetermine different beam profiles at different irradiation positions. In this way, the beam profile can advantageously be flexibly and locally adapted to different conditions or requirements.

[0025] For example, a different beam profile can be selected for the outer enclosure region of the produced component, i.e. in particular for the surface of the component, than for the inner region within the outer enclosure region of the component.

[0026] Alternatively or additionally, for the contour of the area to be cured or the cured area within the powder material layer, i.e., the edge or the outer boundary core, a beam distribution different from the so-called core, i.e., the area within the contour in the powder material layer, can be selected.

[0027] Additionally or alternatively, for the overhang area, yet another beam distribution can be selected, where the overhang area is an area within the powder material layer below which, i.e., beneath it, there is uncured powder material in the powder material layer. Such an overhang is also referred to as "down skin". This term also denotes the lowermost powder material layer including the cured powder material, i.e., the bottom surface of the component.

[0028] Additionally or alternatively, for the covering layer area, yet another beam distribution can be used, where the covering layer area is an area within the powder material layer above which, i.e., above it, there is uncured powder material in the powder material layer. Such a covering layer area is also referred to as "up skin". This term also denotes the uppermost powder material layer still including the cured powder material, i.e., the top surface or the uppermost surface of the component.

[0029] In particular, yet another beam distribution can be selected for the main body area of the produced component, i.e., the following area within the powder material layer, which is surrounded by cured powder material on all sides, especially within the powder material layer, but also above and below the just processed powder material layer in the complete component. Such an area is also referred to as the "inskin" area.

[0030] For fine structures of components, for example, on the order of the beam area, as well as for coarser structures, larger structures, especially two-dimensional structures, different beam distributions can also be used. Optionally, fine structures, especially independent structural segments, can also be produced by generating a local beam distribution only by controlling the deflection device and without controlling the scanning device at a fixed irradiation position, especially by generating a beam distribution in the form of the structural segment to be formed by appropriately controlling the deflection device.

[0031] Predetermining the beam distribution according to the instantaneous irradiation position also enables influencing the microstructure of the produced component via the intensity distribution. For example, when irradiating under changed temperature gradients and curing conditions, the grain structure of the produced component changes. In this way, in particular, the local intensity values or surface hardness can also be influenced, especially locally changed.

[0032] In particular, the outer surface of the component can be hardened by curing powder material that generates greater hardness in the upper or lower skin region of a plurality of powder material layers arranged directly below or above it. Correspondingly, the contour lines can also be cured to have greater hardness over a wider range in each powder material layer.

[0033] In contrast, the outer enclosed region is in particular a region within the powder material layer that has at least one boundary line relative to the uncured powder material within the powder material layer. Such an enclosed region can simultaneously be an overhang, but in the finished component, the enclosed region can also be surrounded by cured powder material above and below the currently produced powder material layer.

[0034] A further aspect of the invention provides that the control device is arranged to predetermine the shape of the beam region as a shape selected from the group comprising: rotationally symmetric shapes, in particular triple rotationally symmetric or higher-order rotationally symmetric shapes, in particular C3 rotationally symmetric shapes, circular shapes, annular shapes, toroidal shapes or circular ring shapes, polygons, rectangles, preferably elongated shapes with rounded corners, linear shapes, irregular shapes, and dot-like shapes. Larger shapes with a greater planar extent are preferably used for rapidly manufacturing regions in the interior skin and / or core region and / or interior region of the component, and thus have high productivity, where more refined and smaller shapes are preferably used for machining in particular fine or delicate enclosed regions or overhangs.

[0035] The control device is preferably arranged to switch or transform between at least two different shapes of the beam region.

[0036] A further aspect of the invention provides that the control device is arranged to generate an intensity distribution as a Gaussian intensity distribution. This can also in particular be a Gaussian distribution elongated along a certain direction within the working area, where in a preferred configuration the longest range axis of the Gaussian distribution can extend perpendicular to the irradiation path, that is, the local displacement direction of the energy beam in the working area, or alternatively along the irradiation path of the energy beam, that is, in the displacement direction. However, the longest range axis of the Gaussian distribution can of course also extend obliquely relative to the irradiation path.

[0037] Alternatively, the control device is preferably arranged to generate an intensity distribution as a non-Gaussian intensity distribution.

[0038] Alternatively or additionally, the control device is arranged to generate an intensity distribution as a constant intensity distribution, in particular of the type of a top-hat beam.

[0039] Alternatively or additionally, the control device is arranged to generate an intensity distribution as an asymmetric intensity distribution or a distorted intensity distribution. Thus, the control device is preferably capable of generating a plurality of different intensity distributions, in particular any desired intensity distribution, and of switching between them.

[0040] A further aspect of the invention provides that the control device is arranged to predetermine the beam distribution, in particular the shape of the beam area, as a function of the instantaneous irradiation position within the component to be manufactured, in particular within the same powder material layer, such that the beam distribution projected onto the working area corresponds to a predefined projected beam distribution.

[0041] This solves the problem of beam distribution distortion in the case of non - perpendicular incidence on the powder material in the working area. In this regard, for example, a circular beam distribution incident on the powder material at an angle to the surface normal of the powder material in the working area is distorted into an ellipse. Correspondingly, an ellipse can be predefined for the beam distribution in such a way that the beam distribution projected onto the powder material is also circular.

[0042] In a preferred further aspect, the control device is arranged to distort the predefined beam distribution such that the projected beam distribution corresponds to one of the beam distributions described in the further aspect above.

[0043] According to a further aspect of the invention, the deflection device is arranged upstream of the scanning device in the propagation direction of the energy beam. In this case, the propagation direction of the energy beam is in particular the propagation direction of the energy radiation in space. The term "upstream" means that during propagation of the energy beam along the propagation direction, the energy beam first reaches the deflection device and then the scanning device. Arranging the deflection device upstream of the scanning device in the propagation direction constitutes a particularly suitable configuration for flexibly generating the beam distribution.

[0044] According to a further aspect of the invention, the deflection device comprises at least one acousto - optic deflector.

[0045] An acousto-optic deflector is to be understood here in particular as an element having a solid body that is transparent to an energy beam and to which acoustic waves, in particular ultrasonic waves, can be applied, and the energy beam is deflected in a manner depending on the frequency of the acoustic waves applied to the transparent solid body as it passes through the transparent solid body. In this process, the acoustic waves generate a grating in particular in the transparent solid body. Advantageously, such an acousto-optic deflector can deflect the energy beam within an angular range very quickly, and the angular range is predetermined by the frequency of the acoustic waves generated in the transparent solid body. In particular, a switching speed of up to 1 MHz can be obtained in this process. The switching time of such an acousto-optic deflector is significantly faster in particular than the typical switching time of conventional scanner optical units, in particular galvanometer scanners, which are generally used to displace the energy beam within the working area of manufacturing apparatuses of the type discussed here. Therefore, such an acousto-optic deflector can be particularly suitable for generating a quasi-static beam profile in the beam area.

[0046] The efficiency of a modern acousto-optic deflector in deflecting an energy beam into a predetermined angular range of first-order diffraction is at least 90%, so that such an acousto-optic deflector is very suitable as a deflection device for the manufacturing apparatus proposed here. In particular, the material that is transparent to the energy beam and the suitable high intensity of the input-coupled ultrasonic waves employed are crucial for the high efficiency.

[0047] In a preferred design, the deflection device has two acousto-optic deflectors that are not oriented parallel to each other, preferably oriented perpendicular to each other. Thus, advantageously, the energy beam can be deflected into two non-parallel directions, in particular perpendicular directions. The acousto-optic deflectors that are not parallel to each other are preferably arranged one downstream of the other along the propagation direction of the energy beam.

[0048] Here, "downstream" particularly means that when the energy beam propagates along the propagation direction, it reaches the element arranged downstream of the other element after the other element, similar to the definition of "upstream" given above.

[0049] A further aspect of the present invention proposes that the manufacturing apparatus has a beam splitter mirror located downstream of the deflection device and upstream of the scanning device along the propagation direction of the energy beam in order to separate the zero-order beam split from the first-order beam split of the energy beam. In particular, if the deflection device has an acousto-optic deflector, the acousto-optic deflector generates a non-diffracted zero-order beam split and a diffracted or deflected first-order beam split due to its grating-like configuration. Only the first-order beam split is intended for irradiating the working area. By means of the beam splitter mirror, then, advantageously, the beam splits of different orders can be separated from each other, and in doing so, only the first-order beam split is transmitted to the working area, in particular to the scanning device. The zero-order beam split is preferably deflected by the beam splitter mirror to a beam trap.

[0050] This explanation is correct for the use of exactly one acousto-optic deflector. If, in a preferred design, two acousto-optic deflectors are used that are not oriented parallel to each other, preferably perpendicular to each other, then the corresponding diffraction orders should also be considered cumulatively: as the useful beam, the ultimate intention is to use the split beam that initially impinges on the second acousto-optic deflector as the first-order split beam of the first acousto-optic deflector and is then diffracted again by the second acousto-optic deflector as the first-order split beam. In this case, the useful beam as the "first-order split beam" can be said to be the first first-order split beam. However, for the sake of brevity in the explanation, only the first order will be mentioned hereinafter.

[0051] In particular, the beam splitter preferably includes a through-hole in the surface that is reflective for the energy beam, and the first-order split beam passes through the through-hole of the beam splitter towards the working area, in particular towards the scanning device. In contrast, the zero-order split beam and preferably also the unwanted split beams higher than the first order impinge on the reflective surface and are deflected by the beam splitter into the beam trap.

[0052] Preferably, the beam splitter is arranged near the intermediate focus of the telescope. This enables the split beams of different orders to be separated particularly clearly.

[0053] Preferably, the beam splitter is not arranged exactly at the intermediate focus of the telescope, in particular in order to avoid damaging the beam splitter due to the too high power density of the energy beam.

[0054] Preferably, the beam splitter is arranged to be offset from the intermediate focus by one-fifth of the focal length of the telescope along the propagation direction, preferably upstream of the intermediate focus along the propagation direction. This ensures both, on the one hand, a clear separation of the different split beams of different orders and, on the other hand, a sufficiently low power density of the energy beam on the beam splitter to avoid damage to the beam splitter by the energy beam.

[0055] The telescope is preferably a 1:1 telescope, i.e., in particular, it neither has the characteristic of reducing the beam nor the characteristic of magnifying the beam. The telescope particularly accomplishes two tasks, namely, in addition to separating the different split beams of different orders, it also preferably images the beam rotation point (also called the pivot point) to a point downstream along the propagation direction of the telescope, and the imaged beam rotation point is preferably located at the pivot point of the downstream scanning device or at the point of the minimum aperture.

[0056] Strictly speaking, this consideration also only applies to the use of a single acousto-optic deflector. If two acousto-optic deflectors that are not oriented parallel to each other, preferably perpendicular to each other, are used, then two beam rotation points occur, i.e., there is one beam rotation point in each acousto-optic deflector. However, if the two acousto-optic deflectors are arranged as close as possible one downstream of the other along the propagation direction, then a single imaginary common beam rotation point can be assumed very approximately and then arranged between the acousto-optic deflectors.

[0057] According to a further aspect of the present invention, the deflection device comprises at least one electro-optical deflector, preferably two electro-optical deflectors that are not parallel to each other, in particular oriented perpendicular to each other. The deflection of the electro-optical deflector (EOD) is based on refraction when passing through an optically transparent material. In the case of using one or two EODs, the foregoing embodiment with an acousto-optical deflector can be modified by replacing one or two acousto-optical deflectors in each case with an EOD.

[0058] According to a further aspect of the present invention, the scanning device comprises at least one scanner, in particular a galvanometer scanner, a piezoelectric scanner, a polygon scanner, a MEMS scanner, and / or a working head or processing head that can be displaced relative to the working area. The scanning device proposed here is particularly suitable for displacing an energy beam between a plurality of irradiation positions within the working area.

[0059] Here, the working head or processing head that can be displaced relative to the working area is particularly understood as an integrated component of the manufacturing device, which comprises at least one radiation outlet for at least one energy beam. The integrated component, i.e., the working head as a whole, can be displaced relative to the working area along at least one displacement direction, preferably along two mutually perpendicular displacement directions. Such a working head can in particular be implemented with a gantry design or be guided by a robot. The working head can in particular be designed as a robotic manipulator.

[0060] According to a further aspect of the present invention, the beam generating device is designed as a laser. The energy beam is thus advantageously generated as a strong beam of coherent electromagnetic radiation, in particular a strong beam of coherent light.

[0061] According to a further aspect of the present invention, the manufacturing device is provided for selective laser sintering. Alternatively or additionally, the manufacturing device is provided for selective laser melting. The design of the manufacturing device has proven to be particularly advantageous.

[0062] This object is also solved by providing a method for changing the beam distribution of an energy beam on the working area of a manufacturing device during the additive manufacturing of a component from a powder material, wherein the energy beam is displaced within the working area to a plurality of irradiation positions in order to manufacture a component from the powder material arranged in the working area by means of the energy beam. The energy beam is displaced to a plurality of beam positions at at least one of the plurality of irradiation positions within the beam area. The beam distribution is changed by changing the displacement of the energy beam within the beam area. In particular, the advantages already described in connection with the manufacturing device are provided in connection with this method.

[0063] According to a further aspect of the present invention, the beam distribution, in particular the shape of the beam area, is changed according to the instantaneous irradiation position within the component to be manufactured, in particular within the same powder material layer, wherein in particular different beam distributions are generated at different irradiation positions.

[0064] According to a further aspect of the present invention, the beam distribution, in particular the shape of the beam area, is changed according to the instantaneous irradiation position within the component to be manufactured, in particular within the same powder material layer, such that the beam distribution projected onto the working area corresponds to a predetermined projected beam distribution. The same advantages as already described in connection with the manufacturing device are obtained with this method.

[0065] Finally, this task is also solved by providing the use of at least one acousto-optic deflector, which is used to change the beam distribution of the energy beam on the working area of the manufacturing device, in particular within the same powder material layer, during the additive manufacturing of a component from powder material. In particular, the advantages as already described in connection with the manufacturing device and method are obtained in connection with the use of the acousto-optic deflector.

[0066] In a preferred embodiment, the acousto-optic deflector is used in the method according to the present invention for changing the beam distribution of the energy beam, or in one of the aforementioned preferred embodiments of such a method.

[0067] Preferably, the acousto-optic deflector is used in the manufacturing device according to the present invention, or in a manufacturing device according to one of the aforementioned embodiments of such a manufacturing device.

[0068] According to a further aspect of the present invention, two acousto-optic deflectors, which are preferably oriented non-parallel to each other, preferably perpendicular to each other, are used to change the beam distribution of the energy beam. Thus, the beam distribution can be changed particularly easily and quickly in two directions that are preferably oriented non-parallel to each other, preferably perpendicular to each other. Description of the Drawings

[0069] The present invention will be specifically described below with reference to the drawings. In the drawings:

[0070] Figure 1 A view of an embodiment of a manufacturing device for additive manufacturing of a component from powder material is shown,

[0071] Figure 2 A schematic diagram showing a plurality of different shapes of the beam area is shown, and

[0072] Figure 3 A simplified diagram for illustrating electro-optical deflection during additive manufacturing is shown. Detailed Description of the Embodiment

[0073] Figure 1The figure shows a schematic illustration of an embodiment of a manufacturing device 1 which is set up for the additive manufacturing of components from powder material. The manufacturing device 1 includes a beam generation device 3 which is set up for generating an energy beam 5. The manufacturing device 1 also has a scanning device 7 which is set up for displacing the energy beam 5 to a plurality of irradiation positions 11 within a working area 9 in order to manufacture a component from the powder material arranged in the working area 9 by means of the energy beam 5.

[0074] The manufacturing device 1 includes a deflection device 13 which is set up for displacing the energy beam 5 to a plurality of beam positions 17 at one of the plurality of irradiation positions 11 within a beam area 15.

[0075] The manufacturing device 1 includes a control device 19 which is operatively connected to the deflection device 13 and is set up for controlling the deflection device 13 and for changing the beam distribution in the beam area 15 during the manufacture of the component by changing the control of the deflection device 13.

[0076] In this way, the beam distribution to be used can be predefined easily and extremely flexibly, and the beam distribution to be used can be changed easily and quickly during the manufacture of the component, in particular during the processing of the same powder material layer, without the need for a specific device which is especially dedicated to generating the beam distribution. In particular, it is possible to switch easily and quickly between different beam distributions.

[0077] The deflection device 13 is especially set up for displacing the energy beam 5 in steps to a plurality of beam positions 17 which are discrete beam positions 17.

[0078] The control device 19 is especially set up for changing, during the manufacture of the component, the shape and / or the intensity distribution in the beam area 15 as the beam distribution.

[0079] The control device 19 is especially set up for predefining the beam distribution, in particular the shape of the beam area 15, as a function of the instantaneous irradiation position 11 within the component to be manufactured. In a preferred design, the control device 19 is set up for predefining different beam distributions at different irradiation positions 11. This can especially be implemented within the same powder material layer, for example in order to expose different areas of the powder material layer, in particular on the one hand an enclosed area and on the other hand an internal area, to different beam distributions. Alternatively or additionally, the beam distribution can especially be selected as a function of whether a distribution, core, overhang area, cladding area or bulk area of the component being produced is being processed.

[0080] Preferably, the control device 19 is set such that the shape of the beam area 15 is predetermined as a shape selected from the group comprising the following shapes: rotationally symmetric shapes, in particular triple rotationally symmetric or higher order rotationally symmetric shapes, circular shapes, annular shapes, toroidal shapes or doughnut shapes, polygons, rectangles, in particular elongated shapes with rounded corners, linear shapes, irregular shapes, and point shapes. The control device 19 is in particular set to switch or change between different shapes of the beam area 15.

[0081] The control device 19 is in particular set to generate an intensity distribution as a Gaussian intensity distribution, a non-Gaussian intensity distribution, a constant intensity distribution, an asymmetric or distorted intensity distribution.

[0082] The deflection device 13 is in particular arranged upstream of the scanning device 7 along the propagation direction of the energy beam 5.

[0083] The deflection device 13 in particular has at least one acousto-optic deflector 21, in particular two acousto-optic deflectors 21 which are not parallel to each other, in particular oriented perpendicular to each other, i.e., a first acousto-optic deflector 21.1 and a second acousto-optic deflector 21.2. Acousto-optic deflectors 21 oriented perpendicular to each other allow the energy beam 5 to be deflected in two mutually perpendicular directions and thus in particular allow two-dimensional scanning of the beam area 15.

[0084] The manufacturing device 1 further has a beam splitter mirror 23 which is located downstream of the deflection device 13 and upstream of the scanning device 7 along the propagation direction of the energy beam 5, and the beam splitter mirror is set to separate the zero-order beam split of the energy beam 5 from the first-order beam split. For this purpose, the beam splitter mirror 23 includes a through hole 25 which is in particular provided in the surface 27 of the beam splitter mirror 23, the surface being reflective for the energy beam 5, and the through hole completely penetrates the beam splitter mirror 23. In this case, the first-order beam split which is intended to be transmitted to the scanning device 7 in a desired manner is guided through the through hole 25 and thus finally reaches the scanning device 7. In contrast, the unwanted zero-order beam split and optionally also unwanted higher-order beam splits impinge on the reflective surface 27 and are deflected into the beam trap 29.

[0085] The beam splitter mirror 23 is in particular arranged near the intermediate focus 31 of the telescope 33, in particular not exactly in the plane of the intermediate focus 31, and is particularly preferably arranged to be offset by a distance of one fifth of the focal length of the telescope 33 along the propagation direction, in particular upstream of the intermediate focus 31. Advantageously, this prevents an excessive power density of the energy beam 5 from hitting the reflective surface 27.

[0086] The telescope 33 preferably includes a first lens 35 and a second lens 37. The telescope is preferably designed as a 1:1 telescope. Preferably, the telescope 33 has a focal length of 500 mm.

[0087] The function of the telescope 33 is preferably twofold: First, the telescope 33 enables the energy beams 5 of different orders deflected by the deflection device 13 to be separated particularly advantageously and clearly, especially in the case of the arrangement of the beam splitter 23 selected here; Second, the telescope 33 preferably images the imaginary, common beam rotation point 39 of the deflection device 13 advantageously onto the pivot point 41 of the scanning device 7.

[0088] Alternatively, the telescope 33 preferably images the beam rotation point 39 onto the point of the minimum aperture.

[0089] To facilitate a compact arrangement of the device 1, the energy beam 5 is preferably deflected multiple times by the steering mirror 43.

[0090] The scanning device 7 preferably includes at least one scanner, especially a galvanometer scanner, a piezoelectric scanner, a polygon scanner, a MEMS scanner, and / or a working head.

[0091] The beam generating device 3 is preferably designed as a laser.

[0092] The manufacturing device 1 is preferably set up for selective laser sintering and / or for selective laser melting.

[0093] Within the framework of a method for changing the beam distribution of the energy beam 5 on the working area 9 of the manufacturing device 1 during the additive manufacturing of a component from powder material, the energy beam 5 is preferably displaced within the working area 9 to a plurality of irradiation positions 11 in order to manufacture a component from the powder material arranged in the working area 9 by means of the energy beam 5. The energy beam 5 is displaced to a plurality of beam positions 17 at at least one of the plurality of irradiation positions 11 within the beam area 15. The beam distribution is changed by changing the displacement of the energy beam 5 within the beam area 15.

[0094] Preferably, the beam distribution, especially the shape of the beam area 15, is changed according to the instantaneous irradiation position 11 within the component to be manufactured, especially within the same powder material layer, wherein different beam distributions are especially generated at different irradiation positions 11.

[0095] Within the framework of using at least one acousto-optic deflector 21, the at least one acousto-optic deflector is used to change the beam distribution of the energy beam 5 on the working area 9 of the manufacturing device 1 during the additive manufacturing of a component from powder material.

[0096] Preferably, in this case, two acousto-optic deflectors 21.1, 21.2 are used, which are especially oriented not parallel to each other, especially perpendicular to each other.

[0097] Figure 2 A schematic view showing various shapes of the beam area 15 is presented.

[0098] Here, a) shows the first, circular shape 51 of the exit beam region 15.

[0099] b) shows the second, polygonal, in particular hexagonal, shape 53 of the exit beam region 15.

[0100] c) shows the third, rectangular shape 55 of the exit beam region 15.

[0101] d) shows the fourth, elongated shape 57 of the exit beam region 15 with rounded ends.

[0102] Finally, e) shows the fifth, annular, toroidal or circular-ring-shaped shape 59 of the exit beam region 15.

[0103] Figure 3 Schematically shows the adjustable deflection of the energy beam 5 using the EOD 131, wherein the refractive index or refractive index gradient of the optically transparent material of the EOD 131 is adjustable by applying a voltage. The deflection of the laser beam 133 changes according to the applied voltage, and the laser beam preferably impinges again on the EOD 131 at the Brewster angle and exits the EOD at a correspondingly adjustable deflection angle. The deflected laser beam 133A can thus be fed to Figure 1 the scanning device 7 in the arrangement of Figure 3 The voltage source 135 can precisely adjust the voltage, which is applied, for example, between the upper and lower sides of the prismatic crystal forming the EOD 131 in G.R.B.E. et al., Physics Procedia 56 (2014) 29 - 39.

Claims

1. A manufacturing device (1) for additive manufacturing of components from powder materials, having: - a beam generation device (3) configured to generate an energy beam (5), - a scanning device (7) configured to displace the energy beam (5) to a plurality of irradiation positions (11) within a working area (9) in order to manufacture a component from powder material arranged in the working area (9) by means of the energy beam (5), - a deflection device (13) configured to displace the energy beam (5) to a plurality of beam positions (17) within a beam area (15) at one of the plurality of irradiation positions (11), and - a control device (19) operatively connected to the deflection device (13) and configured to control the deflection device (13) and to change the beam distribution in the beam area during component manufacturing by changing the control of the deflection device (13), The manufacturing device has a separation mirror located downstream of the deflection device and upstream of the scanning device along the propagation direction of the energy beam, so as to separate the zero-order beam splitting from the first-order beam splitting of the energy beam. The separation mirror is arranged near the intermediate focus of the telescope of the manufacturing device (1).

2. The manufacturing apparatus (1) according to claim 1, wherein, The deflection device (13) is configured to displace the energy beam (5) in a stepwise manner to a discrete plurality of beam positions (17).

3. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The control device (19) is configured to change, during manufacturing of the component, the shape and / or the intensity distribution in the beam area (15) as the beam distribution.

4. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The control device (19) is configured to predetermine the beam distribution according to the instantaneous irradiation position (11) within the component to be manufactured.

5. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The control device (19) is configured to predetermine the shape of the beam area (15) as a shape selected from the group including: rotationally symmetric shape, irregular shape, and dot shape.

6. The manufacturing apparatus (1) according to claim 3, wherein, The control device (19) is configured to generate the intensity distribution as a Gaussian intensity distribution, a non-Gaussian intensity distribution, a constant intensity distribution, an asymmetric intensity distribution, or a distorted intensity distribution.

7. The manufacturing apparatus (1) according to claim 4, wherein, The control device (19) is configured to predetermine the beam distribution according to the instantaneous irradiation position (11) within the component to be manufactured such that the beam distribution projected onto the working area (9) corresponds to a predetermined projected beam distribution.

8. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The deflection device (13) is arranged upstream of the scanning device (7) along the propagation direction of the energy beam (5).

9. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The deflection device (13) has at least one acousto-optic deflector (21).

10. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The deflection device (13) has at least one electro-optic deflector (21).

11. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The scanning device (7) has at least one scanner and / or a working head displaceable relative to the working area (9).

12. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The beam generation device (3) is designed as a laser.

13. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The manufacturing device (1) is configured for selective laser sintering and / or for selective laser melting.

14. The manufacturing apparatus (1) according to claim 4, wherein, The control device (19) is configured to predetermine the shape of the beam area (15) based on the instantaneous irradiation position (11) within the same powder material layer, and to predetermine different beam distributions at different irradiation positions (11).

15. The manufacturing apparatus (1) according to claim 5, wherein, The rotationally symmetric shape is a triple rotationally symmetric or higher order rotationally symmetric shape.

16. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The control device (19) is configured to predetermine the shape of the beam area (15) as a circular shape, an annular shape, a polygon, or a linear shape.

17. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The control device (19) is configured to predetermine the shape of the beam area (15) as a rectangle.

18. The manufacturing apparatus (1) according to claim 1 or 2, wherein, The control device (19) is configured to predetermine the shape of the beam area (15) as an elongated shape with rounded corners.

19. The manufacturing apparatus (1) according to claim 9, wherein, The deflection device (13) has two acousto-optic deflectors (21) oriented non-parallel to each other.

20. The manufacturing apparatus (1) according to claim 9, wherein, The deflection device (13) has two acousto-optic deflectors (21) oriented perpendicular to each other.

21. The manufacturing apparatus (1) according to claim 10, wherein, The deflection device (13) has two electro-optic deflectors (21) oriented non-parallel to each other.

22. The manufacturing apparatus (1) according to claim 10, wherein, The deflection device (13) has two electro-optic deflectors (21) oriented perpendicular to each other.

23. The manufacturing apparatus (1) according to claim 11, wherein, The scanner is a galvanometer scanner, a piezoelectric scanner, a polygon scanner, or a MEMS scanner.

24. A method for changing the beam distribution of an energy beam (5) on a working area (9) of a manufacturing device (1) during the additive manufacturing of a component from a powder material, wherein, The energy beam (5) is shifted to a plurality of irradiation positions (11) within the working area (9) in order to produce the component by means of the energy beam (5) from the powder material arranged in the working area (9), wherein, at at least one of the plurality of irradiation positions (11), the energy beam (5) is shifted to a plurality of beam positions (17) within the beam area (15), and wherein the beam distribution is changed by changing the shift of the energy beam (5) within the beam area (15), and the manufacturing device (1) is a manufacturing device according to any one of claims 1 to 23.

25. The method according to claim 24, wherein The beam distribution is changed based on the instantaneous irradiation position (11) within the component to be manufactured.

26. The method according to claim 25, wherein The shape of the beam area (15) is changed based on the instantaneous irradiation position (11) within the same powder material layer, and different beam distributions are produced at different irradiation positions (11).

27. The method according to any one of claims 24 to 26, wherein, The beam distribution is changed based on the instantaneous irradiation position (11) within the component to be manufactured such that the beam distribution projected onto the working area (9) corresponds to a predetermined projected beam distribution.

28. An application of at least one acousto-optic deflector (21) for changing the beam distribution of an energy beam (5) on the working area (9) of a manufacturing device (1) during the additive manufacturing of a component from powder material, the manufacturing device (1) being a manufacturing device according to any one of claims 1 to 23.

29. The application according to claim 28, wherein, Use two acousto-optic deflectors oriented non-parallel to each other.

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