Method and apparatus for additively manufacturing a component layer from at least one powder layer, and use thereof

Abstract

The invention relates to a method for additively manufacturing a component layer (12) from at least one powder layer (14). In this method, at least one irradiation position (P1, P2, P3, P4, P5, P6) is provided on the powder layer (14), and a planar irradiation pattern (48) and / or a beam profile (50) is assigned to the irradiation position (P1, P2, P3, P4, P5, P6). Furthermore, the powder layer (14) is irradiated in the region of the irradiation position (P1, P2, P3, P4, P5, P6) by means of an energy beam (40). The energy beam (40) is guided along the planar irradiation pattern (48), which is referenced to the irradiation position (P1, P2, P3, P4, P5, P6). Alternatively or additionally, the energy beam (40) has the beam profile (50). The invention also relates to the use of an irradiation-position-specific planar irradiation pattern (48) and / or an irradiation-position-specific beam profile (50). The invention also relates to an apparatus for additively manufacturing a component layer (12) from at least one powder layer (14), which apparatus is designed to carry out such a method.

Description

[0001] Method and device for the additive production of a component layer from at least one powder layer and use

[0002] The invention is directed to a method for the additive production of a component layer from at least one powder layer.

[0003] Furthermore, the invention relates to a use and a device for the additive production of a component layer from at least one powder layer.

[0004] Such processes, in which materials are applied layer by layer, can also be referred to as generative manufacturing processes. The materials can be provided in the form of powder or wire. Such processes are characterized by the fact that a three-dimensional component to be produced is assembled from several component layers in a near-net shape. It must also be ensured that the material properties of the component or component layer produced in this way lie within a specified target range. Examples of material properties in this context include the presence of pores and their size, a microstructure, a surface roughness and / or a hardness of the component surface.

[0005] The object of the present invention is therefore to improve processes for the additive manufacturing of a component layer with regard to the material properties to be achieved. In particular, the targeted adjustment of material properties should be facilitated. This object is achieved by a process for the additive manufacturing of a component layer from at least one powder layer. The process comprises:

[0006] - Providing at least one irradiation position on which Pul shifts,

[0007] - Assigning a planar irradiation figure and / or a beam profile to the irradiation position, and

[0008] - Irradiating the powder layer in the region of the irradiation position by means of an energy beam, wherein the energy beam is guided along the planar irradiation figure which is referenced to the irradiation position, and / or wherein the energy beam has the beam profile.

[0009] In this context, providing an irradiation position means specifying an irradiation position or obtaining information describing the irradiation position. A range of the irradiation position further means that not only a point coincident with the irradiation position is irradiated, but also the immediate vicinity of this point can be irradiated. In this case, the irradiation pattern either intersects or covers the irradiation position, or the irradiation position lies within the irradiation pattern. Referencing is therefore to be understood as positional referencing of the irradiation pattern. In this case, an irradiation pattern refers to a local path on a surface of the powder layer along which the energy beam moves while directed onto the powder layer.The fact that the irradiation pattern is referenced to the irradiation position makes it clear that such an irradiation pattern is to be understood as independent of the local external geometry of the component to be manufactured. Moving along an external contour of a component section to be manufactured and / or a surface of a component section to be manufactured is therefore not understood as moving along an irradiation pattern. Furthermore, the beam profile is to be understood as an intensity distribution in a cross-section of the energy beam. This beam profile is specific or individual to the irradiation position. It is understood that, in a conventional manner, a beam power must also be specified for each irradiation position.

[0010] The method according to the invention thus comprises three alternatives. In a first alternative, a planar irradiation pattern is assigned to the irradiation position, and the powder layer in the region of the irradiation position is irradiated by means of the energy beam, with the energy beam being guided along the planar irradiation pattern. In the first alternative, therefore, no irradiation position-specific beam profile is assigned to the irradiation position. Naturally, the energy beam exhibits a certain beam profile. However, this beam profile is not specific or individual to the irradiation position. In such a case, the beam profile can be defined, for example, for the entire component to be manufactured, for a component layer to be manufactured, and / or for a section of the component to be manufactured.In a second alternative, a beam profile is assigned to the irradiation position, and the powder layer in the region of the irradiation position is irradiated using the energy beam, the energy beam having the beam profile. In this alternative, the beam profile is assigned to the irradiation position. This means that the beam profile is specific or individual to the irradiation position. In other words, in this alternative, the beam profile is defined for each irradiation position and not for a higher-level section of the component or component layer to be manufactured. However, this does not preclude the same beam profile from being assigned to multiple irradiation positions. In this context, the beam profile can, for example, remain the same for a component section or for a surface of the component to be manufactured. The beam profile can also be the same for a partial surface of the component to be manufactured.A third alternative is a combination of the first alternative and the second alternative. By assigning a flat irradiation pattern and / or beam profile to an irradiation position and irradiating the area of ​​the irradiation position accordingly with the energy beam, the energy input into the powder layer can be adjusted with irradiation position precision or pinpoint accuracy. This particularly applies to the distribution of the energy input across the area of ​​the irradiation position. If multiple irradiation positions are provided, the energy input can be adjusted separately for each of the irradiation positions. In particular, the distribution of the energy input across the area of ​​the respective irradiation position can also be precisely adjusted. In this way, the material properties of the component layer to be produced can be defined and achieved with high precision and reliability.For example, using the method according to the invention, the presence and size of pores can be specifically adjusted. Likewise, the microstructure, surface roughness, and / or hardness of the component surface can be specifically influenced in the desired manner by selecting a suitable planar irradiation pattern and / or a suitable beam profile.

[0011] In connection with the method according to the invention, the energy beam can be guided continuously along the planar irradiation pattern. In this case, the powder layer is irradiated by means of a continuous energy beam, i.e. the energy beam is not interrupted or switched off when moving along the irradiation pattern. Alternatively, the planar irradiation pattern can be approximated by a group of irradiation points and / or line segments. In this case, the powder layer is only irradiated at these irradiation points and / or line segments. The irradiation pattern results from the totality of the irradiation points and / or line segments. Mixed forms are also possible, i.e. the irradiation pattern is represented in terms of control technology by a group of irradiation points and / or line segments, but the energy beam is not switched off when moving between irradiation points and / or line segments.This hybrid form is particularly simple in terms of control technology. Furthermore, the energy beam can be moved relatively quickly between irradiation points or line segments, so that the energy input when moving the energy beam between irradiation points or line segments can be negligible.

[0012] In a case where both a planar irradiation pattern and a beam profile are assigned to the irradiation position, the powder layer in the region of the irradiation position can be irradiated using the energy beam, with the energy beam being guided along the planar irradiation pattern, which is referenced to the irradiation position, and the energy beam exhibiting the beam profile. In such a case, the beam profile is preferably generated by guiding the energy beam along the planar irradiation pattern. This will be explained in more detail below under the term "beam shaping."

[0013] In one embodiment, the component layer to be produced using the method according to the invention is a lower boundary layer of the component to be produced. Such a lower boundary layer can also be referred to as a down skin. The lower boundary layer is thus a layer of the component to be produced that forms a component outer surface facing away from the source of the energy beam. Such a component outer surface therefore has a surface normal that has at least one extension component that runs in the beam direction or parallel to the beam direction of the energy beam. For lower boundary layers, the fact that material properties of the component layer to be produced can be defined and achieved with high precision and reliability by applying the method according to the invention is particularly advantageous.

[0014] It is understood that, according to the present invention, a planar irradiation pattern and / or a beam profile is assigned to the irradiation position. In other words, the planar irradiation pattern is irradiation position-specific and / or the beam profile is irradiation position-specific. It is thus conceivable to use a different irradiation pattern and / or a different beam profile at each irradiation position. However, it is equally conceivable to assign the same irradiation pattern and / or beam profile to irradiation positions that lie within a surface or partial surface of the component to be manufactured. In other words, the irradiation pattern and / or the beam profile are the same for all irradiation positions within the surface or partial surface. This also falls under the irradiation position-specific assignment and use of a planar irradiation pattern and / or a beam profile.It is also conceivable that the same irradiation pattern and / or beam profile is assigned to all irradiation positions of the component to be manufactured. In other words, the irradiation pattern and / or beam profile are the same for all irradiation positions of the component to be manufactured. This also falls under the irradiation-position-specific assignment and use of a planar irradiation pattern and / or beam profile. The decisive factor in all of the above variants is that the planar irradiation pattern and / or beam profile are irradiation-position-specific, i.e., are assigned to an irradiation position.

[0015] The method according to the invention can be used for both preheating and melting. Preheating differs from melting in that no molten pool is generated during preheating, whereas a molten pool is present during melting.

[0016] According to one embodiment, the irradiation pattern comprises a circular line segment, a circular line, an elliptical line segment, an elliptical line, a curved segment, a polygon segment, a spiral contour, and / or a meandering line. Examples of polygon segments are triangular contours, quadrilateral contours, e.g., rectangles or squares, and sections thereof. The irradiation pattern can also be composed of several of the aforementioned lines and / or segments. For example, the irradiation pattern can comprise at least two concentric circles. It is also possible for the irradiation pattern to comprise a spiral line. This may or may not include the center point of the spiral line. A cloverleaf shape can also be composed of several curved segments. An alternative term for an irradiation pattern is a grid pattern or an oscillation pattern. As already mentioned, material properties can be specifically influenced by the choice of an irradiation pattern.In this case, this is done with irradiation position precision or with pinpoint accuracy. For example, beam patterns that have an empty space in the area of ​​their center, i.e. an area over which the energy beam is not moved, can be used to specifically create pores. Accordingly, beam patterns in which the energy beam also moves over the center can be used to specifically avoid pores. The energy beam can be guided along the irradiation pattern within less than 1 millisecond, preferably within less than 100 microseconds. The irradiation pattern is therefore traversed comparatively quickly. This high speed is necessary in order to be able to specifically influence material properties. In one example, the energy beam is guided along the irradiation pattern within 10 microseconds to 90 microseconds, preferably within 30 microseconds to 45 microseconds.

[0017] The energy beam can also be guided multiple times along the planar irradiation pattern, preferably at a frequency of 500 Hertz or more. More preferably, the frequency is 800 Hertz or more, in particular 1000 Hertz or more. It is also possible for the frequency to be 1200 Hertz or more, or 1500 Hertz or more. Such a frequency can also be referred to as the irradiation frequency or oscillation frequency. The frequency describes how often an irradiation pattern is traversed per unit of time. In a case in which the irradiation pattern is composed of a plurality of points or lines, the irradiation frequency or oscillation frequency can also specify the number of points of the irradiation pattern that are traversed per unit of time.However, the fact that the frequency is specified with a standardization to one second does not mean that the energy beam is necessarily guided along the planar irradiation pattern for one second or even longer. Rather, it is preferable to guide the energy beam along the planar irradiation pattern for a period of time significantly less than one second. In one embodiment, the frequency is 1000 hertz or more. In the example already mentioned, in which the energy beam is guided along the planar irradiation pattern within 30 microseconds to 45 microseconds and this occurs multiple times, the frequency is therefore 22.2 kilohertz to 33.3 kilohertz. The irradiation pattern can be traversed a total of 10 times, resulting in a total duration of 0.3 milliseconds to 0.45 milliseconds.By selecting an appropriate frequency, the power or energy as well as its local distribution in the powder layer can be precisely adjusted. In one variant, the beam profile of the energy beam is generated using beam shaping. In this case, the beam profile is indirectly manipulated. This means that the beam profile itself remains unchanged at the output of the beam source, but the beam is deflected at high speed. Since this type of beam deflection and the absorption of the energy beam occur very quickly in relation to the typical heat propagation in the material, i.e. in the powder layer, which is determined by thermal diffusivity, the beam profile does not have an individual effect at each deflection position; rather, the irradiated material, i.e. the powder layer, perceives the energy input as an envelope or overall beam profile.In other words, the beam profile remains the same, but the beam is deflected so quickly that the beam profiles at the individual deflection positions are smeared or superimposed, and only the smeared or superimposed beam profiles are effective in the powder layer. The energy beam is preferably moved at a shaping frequency of 500 Hertz or more. More preferably, the shaping frequency is 800 Hertz or more, in particular 1000 Hertz or more. It is also possible for the shaping frequency to be 1200 Hertz or more, or 1500 Hertz or more. In another example, the shaping frequency is 10,000 Hertz or more. This allows beam profiles with, for example, a flattened top, a ring shape, or a polygonal base to be created without having to manipulate the raw beam.

[0018] In a preferred embodiment, as already mentioned, the beam profile is generated by guiding the energy beam along the planar irradiation pattern. In this context, the previously discussed beam shaping process takes place by guiding the energy beam along the planar irradiation pattern. As already mentioned, this requires the energy beam to traverse the irradiation pattern sufficiently quickly. In such a case, the shaping frequency corresponds to the irradiation frequency or oscillation frequency.

[0019] The irradiation position can be defined as a point on a point grid. The point grid can extend at least partially across the powder layer. A point grid represents a simple and reliable way of determining irradiation positions on a powder layer. Furthermore, the point grid can be used to define the irradiation pattern. In a case where the irradiation pattern is composed of individual points, these individual points can be defined on the point grid. In a case where the irradiation pattern comprises one or more continuous segments, these can also be defined on the point grid. Thus, irradiation patterns can also be determined relatively easily using the point grid.

[0020] In one embodiment, at least one energy beam parameter characterizing the energy beam is changed while the energy beam is guided along the planar irradiation pattern. Thus, this energy beam parameter is different at different positions along the planar irradiation pattern. In this way, energy input into the powder layer can be adjusted on an even smaller scale. Thus, the material properties can be influenced even on this small scale.

[0021] The at least one energy beam parameter can be selected from a group comprising beam intensity, beam diameter, and travel speed. If the beam intensity is changed, the energy input along the irradiation pattern changes. The energy distribution can also be influenced by changing the beam diameter and the travel speed, whereby the beam diameter can be defined as a so-called 4 sig diameter, full width diameter, half max diameter, or full width half max diameter. In this context, the beam diameter is always determined based on an intensity distribution in the beam cross-section. The intensity distribution is usually bell-shaped. The 4 sig diameter therefore refers to the beam diameter that corresponds to a range of two standard deviations (sigma) around a beam center axis, i.e.A beam diameter corresponding to the intensity range from -2 sigma to +2 sigma. The full-width diameter refers to the total width of the intensity profile or intensity distribution. The half-max diameter is the diameter resulting from the edges of the intensity distribution when it is intersected at 50% of the maximum intensity. The full-width half-max diameter is defined in the same way as the half-max diameter. If the energy beam is an electron beam, the beam current and / or deflection speed can be influenced.

[0022] Within the scope of the method according to the invention, it is also possible to focus the energy beam on a point of the irradiation pattern and / or to traverse the irradiation pattern with a focused energy beam. A focused energy beam is understood to mean that the energy beam is bundled onto a point, e.g. by means of focusing optics. In a case in which the energy beam is an electron beam, the focusing optics is an electron optic, e.g. a magnetic lens. Alternatively, the energy beam can be defocused with respect to the irradiation pattern. Material properties can also be influenced in a targeted manner in this way. In this context, a defocused energy beam can be defined, for example, with reference to an ideally focused energy beam, i.e. with reference to a minimum beam diameter that the energy beam has in the focused state. The energy beam can therefore be described as defocused, e.g.can be considered to be a focused beam if the beam diameter is 150%, 200%, or 300% of the minimum beam diameter of the energy beam in the focused state. In one example, the minimum beam diameter in the focused state is 200 micrometers.

[0023] In one example, at least two irradiation positions are provided on the powder layer. Each of the at least two irradiation positions is / are assigned a planar irradiation pattern and / or a beam profile. The powder layer is irradiated in the region of each of the at least two irradiation positions using the energy beam, wherein the energy beam is guided along the planar irradiation patterns referenced to the respectively assigned irradiation position, and / or wherein the energy beam has the respectively assigned beam profile. Thus, the energy input can be adjusted separately for each of the irradiation positions. In particular, the distribution of the energy input across the region of the respective irradiation position can also be precisely adjusted. In this way, material properties of the component layer to be produced can be defined and achieved with high precision and reliability.These can be different for each irradiation position. In other words, the irradiation pattern and / or beam profile can be selected according to local requirements. For example, the presence and size of pores can be specifically adjusted. Likewise, the microstructure, surface roughness, and / or hardness of the component surface can be specifically influenced in the desired manner by selecting a suitable planar irradiation pattern and / or beam profile.

[0024] In a case where at least two irradiation positions are provided on the powder layer, a different irradiation pattern and / or beam profile can be used at each irradiation position. Alternatively, multiple irradiation positions can be grouped or clustered. In such a case, the same irradiation pattern and / or beam profile can be used for each irradiation position of the same group or cluster. Consequently, the irradiation pattern and / or beam profile need to be changed less frequently. This increases the efficiency of the process.

[0025] The at least two irradiation positions can be spaced apart by a positional distance. The positional distance can be greater than, less than, or equal to a melt pool diameter. The positional distance thus represents a further parameter for influencing the material properties. If the positional distance is greater than a melt pool diameter, melt pools at adjacent irradiation positions do not touch each other. If the positional distance is equal to or less than a melt pool diameter, melt pools at adjacent irradiation positions touch or overlap. In this way, the microstructure of the component layer to be produced can be specifically influenced.

[0026] In one variant, the irradiation figures assigned to the at least two irradiation positions are connected by means of an irradiation path. This means that the energy beam acts on the powder layer even when it travels from one of the at least two irradiation positions, more precisely from an assigned irradiation figure, to the other of the at least two irradiation positions, i.e. the assigned irradiation figure. This irradiation path can be traversed comparatively quickly. In other words, the energy beam can be deflected comparatively quickly along the irradiation path. In this case, any influence on the powder layer is comparatively small. Alternatively, the irradiation path can be traveled at a lower speed along the irradiation path, i.e., deflected at a lower speed along the irradiation path.In this alternative, the impact on the powder layer is greater and usually desired. The speed is therefore selected so that the desired effect occurs in the powder layer. In both cases, the powder layer can be processed entirely with a closed, i.e., continuous, beam path. The individual irradiation patterns are thus combined into a macro pattern. This enables efficient production of the component layer.

[0027] The energy beam can be pulsed. This means that the energy beam does not act continuously on the powder layer, but rather regularly in time-limited portions. In other words, the energy beam is periodically switched on and off. This allows high energy beam intensities to be achieved, which can be precisely introduced into the powder layer. Furthermore, a pulsed energy beam can be coordinated with a travel speed or deflection speed. In this context, a point or section of an irradiation pattern can be achieved with a single pulse of the pulsed energy beam. The next point or section of the irradiation pattern is achieved with the next pulse.

[0028] The energy beam can be an electron beam. This type of energy beam has the advantage that it can be directed onto the powder layer with the utmost precision. Furthermore, this type of energy beam has a relatively high energy density. Furthermore, its orientation can be changed—i.e., deflected—at high speed and with great precision. This makes the electron beam particularly well-suited for this process, which requires moving the energy beam at high speed and with great precision.

[0029] According to one embodiment, the energy beam is guided along the planar irradiation pattern by means of a deflection unit. Alternatively or additionally, the beam profile is generated by deflecting the energy beam by means of a deflection unit. In all of the aforementioned variants, the deflection unit comprises several magnetic coils. In this context, the energy beam is preferably an electron beam. This can be deflected easily, quickly, and precisely by means of such a deflection unit, so that the energy beam can be guided easily, quickly, and precisely along the planar irradiation pattern. Furthermore, the beam profile can be generated easily, quickly, and reliably in this way. The previously explained beam shaping can also be used for this purpose.

[0030] The problem is also solved by using an irradiation-position-specific planar irradiation pattern and / or an irradiation-position-specific beam profile for the additive production of a component layer from at least one powder layer by irradiation with an energy beam. By assigning a planar irradiation pattern and / or a beam profile to an irradiation position and irradiating the area of ​​the irradiation position accordingly with the energy beam, the energy input into the powder layer can be adjusted with irradiation position precision or pinpoint accuracy. This particularly concerns a distribution of the energy input across the area of ​​the irradiation position. If multiple irradiation positions are provided, the energy input can be adjusted separately for each of the irradiation positions.In particular, the distribution of the energy input across the area of ​​the respective irradiation position can be precisely adjusted. In this way, the material properties of the component layer to be produced can be defined and achieved with high precision and reliability. For example, using the method according to the invention, the presence and size of pores can be specifically adjusted. Likewise, the microstructure, surface roughness, and / or hardness of the component surface can be specifically influenced in the desired manner by selecting a suitable planar irradiation pattern and / or a suitable beam profile.

[0031] Furthermore, the object is achieved by a device for the additive production of a component layer from at least one powder layer, which is configured to carry out a method according to the invention. By means of the device, a flat irradiation figure and / or a beam profile can be assigned to an irradiation position and the area of ​​the irradiation position can be irradiated accordingly using the energy beam. The energy input into the powder layer can thus be adjusted with irradiation position precision or with pinpoint accuracy. This particularly relates to a distribution of the energy input over the area of ​​the irradiation position. In the event that multiple irradiation positions are provided, the energy input can be adjusted separately for each of the irradiation positions. In particular, the distribution of the energy input over the area of ​​the respective irradiation position can therefore also be precisely adjusted.In this way, the material properties of the component layer to be produced can be defined and achieved with high precision and reliability. For example, using the device according to the invention, the presence and size of pores can be specifically adjusted. Likewise, the microstructure, surface roughness, and / or hardness of the component surface can be specifically influenced in the desired manner by selecting a suitable planar irradiation pattern and / or a suitable beam profile.

[0032] According to one embodiment, the device further comprises a deflection unit with a plurality of magnetic coils for guiding the energy beam along the planar irradiation pattern and / or for generating the beam profile by deflecting the energy beam. In this context, the energy beam is preferably an electron beam. This can be easily, quickly, and precisely deflected by means of such a deflection unit, so that the energy beam can be easily, quickly, and precisely guided along the planar irradiation pattern. Furthermore, the beam profile can be generated easily, quickly, and reliably in this way. The previously explained beam shaping method can also be used for this purpose.

[0033] It is understood that effects, advantages and features mentioned above only in connection with one of the inventive method, inventive use and inventive device also apply in the same way to all other of the inventive method, inventive use and inventive device.

[0034] The invention is explained below using various embodiments shown in the accompanying drawings. They show:

[0035] Figure 1 shows a device according to the invention for the additive production of a

[0036] Component layer made of at least one powder layer, wherein a method according to the invention is carried out by means of the device according to the invention,

[0037] Figure 2 is a view of a section of the powder layer along a

[0038] Direction II in Figure 1, wherein the section is processed into a component layer by means of the device from Figure 1 and wherein a processing sequence of different irradiation positions is indicated,

[0039] Figure 3 is a view corresponding to Figure 2, wherein one of

[0040] a planar irradiation figure associated with the irradiation position and a beam profile associated with the irradiation position are illustrated,

[0041] Figure 4 is a schematic view showing several irradiation figures connected to a macro figure,

[0042] Figure 5 shows an overview of various irradiation figures, Figure 6 shows schematically two examples of how irradiation figures can be combined to form a macro figure, and

[0043] Figures 7 to 14 show different beam profiles that can be realized using the device of Figure 1.

[0044] Figure 1 shows a device 10 for the additive production of a component layer 12 from at least one powder layer 14.

[0045] In the example shown in Figure 1, a component is constructed three-dimensionally from a plurality of such component layers 12. It is understood that the component layers 12 shown are merely illustrative.

[0046] Each component layer 12 is made from a powder layer 14.

[0047] The device 10 comprises a vacuum chamber 16 in which a construction area 18 is provided. The construction area 18 is delimited by lateral walls 20. Furthermore, a base plate 22 is provided on an underside of the construction area 18, which defines the lower boundary of the construction area 18. The base plate 22 is coupled to a lifting unit 24, by means of which the base plate 22 can be moved vertically.

[0048] Construction area 18 is open at the top.

[0049] The device 10 further comprises a powder reservoir 26, which is bounded laterally by walls 28 and downwardly by a base plate 30. The base plate 30 is also coupled to a lifting unit 32, by means of which the base plate 30 can be moved vertically.

[0050] The powder reservoir 26 is also open at the top. Furthermore, the device includes a doctor blade 34, which can be moved along a direction represented by an arrow 36 within the vacuum chamber 16. Using the doctor blade 34, powder can be transferred from the powder reservoir 26 into the build area 18.

[0051] A powder layer 14 can therefore be created in the build area 18 by the coordinated interaction of the squeegee 34, the lifting unit 24 of the build area 18, and the lifting unit 32 of the powder reservoir 26. For this purpose, the base plate 22 of the build area 18 is lowered by one increment using the lifting unit 24. The base plate 30 of the powder reservoir 26 is raised by one increment using the lifting unit 32. This results in a portion of the powder provided in the powder reservoir 26 projecting vertically beyond the wall 28 laterally delimiting the powder reservoir 26. This portion of the powder can then be transferred into the build area 18 by moving the squeegee 34 along the arrow 36, starting from the position shown in Figure 1. In this process, the squeegee 34 is moved into the area of ​​the lateral wall 20 of the build area 18 that faces away from the powder reservoir 26. In this way, a powder layer 14 with a substantially constant thickness is generated in the build area 18.

[0052] In addition, the device 10 comprises a beam generating unit 38 which is designed to generate an energy beam 40.

[0053] In the illustrated embodiment, the energy beam is a pulsed electron beam.

[0054] In addition, the beam generation unit 38 also includes a deflection unit 42. The deflection unit 42 includes a plurality of magnetic coils, by means of which the energy beam 40 can be oriented within the build area 18. This means that the energy beam 40 can be selectively directed at different points within the build area 18 by means of the deflection unit 42. In this case, the energy beam 40 can fuse those sections of the powder layer 14 at which it is directed into a section of the component layer 12 to be produced. Sections of the powder layer 14, at which the energy beam 40 is not directed, remain powdery. In Figure 1, powdery sections are therefore illustrated by dots. The component layers 12 are shown schematically, as already explained.

[0055] The device 10 is further configured to carry out a method for the additive production of a component layer 12 from at least one powder layer 14.

[0056] This procedure is explained below with reference to Figures 2 to 14.

[0057] Figures 2 and 3 show a section 44 of the powder layer 14, which is to be processed into a component layer 12 by means of the energy beam 40.

[0058] A dot grid 46 is provided that extends over the powder layer 14 and thus over the section 44 of the powder layer 14. The dot grid 46 comprises a plurality of dots that are regularly arranged. In other words, the dot grid 46 comprises a regular dot grid.

[0059] In a first step S1 of the method, at least one irradiation position is determined on the powder layer 14. The irradiation position is defined as a point of the point grid 46.

[0060] In the example shown in Figure 2, a total of six irradiation positions P1, P2, P3, P4, P5, and P6 are provided. It is understood that these irradiation positions P1, P2, P3, P4, P5, and P6 are purely illustrative.

[0061] Furthermore, during the first step S1, a processing sequence is defined, i.e., a sequence is established in which the various irradiation positions are approached by means of the energy beam 40. In Figure 2, the processing sequence is illustrated, on the one hand, by the numbering of the irradiation positions PI, P2, P3, P4, P5, P6 and, on the other hand, by arrows between the individual irradiation positions PI, P2, P3, P4, P5, P6. Depending on the application, a position distance d between two irradiation positions PI, P2, P3, P4, P5, P6 can be selected to be greater than, equal to, or smaller than a melt pool diameter.

[0062] In a second S2 step of the method, a planar irradiation figure 48 and a beam profile 50 are assigned to each of the irradiation positions PI, P2, P3, P4, P5, P6.

[0063] Irradiation pattern 48 is explained below using Figures 3 and 4 and irradiation position P6. The same applies to the remaining irradiation positions P1, P2, P3, P4, and P5.

[0064] In the example of Figure 3, the irradiation figure 48 is a spiral contour. This is referenced to the assigned irradiation position P6, i.e., to a point of the point grid 46.

[0065] This means that in a subsequent third step S3 of the method, the powder layer 14 is irradiated in the region of the irradiation position P6 by means of the energy beam 40 by guiding the energy beam 40 along the planar irradiation figure 48, ie along the spiral contour.

[0066] The other irradiation positions PI, P2, P3, P4, P5 are each assigned an irradiation figure 48 in the same way.

[0067] In addition, the individual irradiation patterns 48 are connected by an irradiation path 52. This means that the energy beam 40 acts on the powder layer 14 even if it is first moved from one irradiation pattern 48 to the other. This is illustrated schematically in Figure 4. The individual irradiation positions in Figure 4 do not correspond to the irradiation positions P1, P2, P3, P4, P5, P6 in Figures 2 and 3.

[0068] In this case, the irradiation patterns 48 and the irradiation paths 52 are represented as continuous lines. This is an option. The powder layer 14 is then irradiated using a continuous energy beam 40. Alternatively, the irradiation patterns 48 and irradiation paths 52 represented by continuous lines can also be approximated by a group of irradiation points or line segments. This is particularly advantageous in combination with the pulsed energy beam 40, since each pulse of the energy beam 40 can be assigned to a respective irradiation point or line segment.

[0069] In the illustrated embodiment, each irradiation pattern 48 is scanned within 34 microseconds. This can also be expressed as a frequency. In this case, each irradiation pattern is scanned at a frequency of 2.9 kilohertz.

[0070] It goes without saying that in other examples the irradiation pattern can also be traversed multiple times.

[0071] In this context, Figure 5 shows a selection of irradiation figures 48.

[0072] In the variant from Figure 5a), the irradiation figure 48 corresponds to a closed circular line.

[0073] In the variant from Figure 5b), the irradiation figure 48 corresponds to a total of three concentrically arranged circular lines.

[0074] The different intensity levels with which the concentrically arranged circular lines are depicted mean that each of the concentrically arranged circular lines is traversed using a different energy beam parameter that characterizes the energy beam 40. In other words, the energy beam parameter is changed between the concentrically arranged circular lines.

[0075] The energy beam parameter can be selected from the group consisting of beam intensity, beam diameter, and travel speed. For example, a relatively thick line represents a relatively high beam intensity, and a relatively thin line represents a relatively low beam intensity. Similarly, a relatively thick line can represent a relatively large beam diameter, and a relatively thin line represents a relatively small beam diameter. Similarly, a relatively thick line can represent a relatively high travel speed, and a relatively thin line represents a relatively low travel speed.

[0076] In the variant from Figure 5c), the irradiation figure 48 corresponds to a closed triangle.

[0077] Also in the variant of Figure 5d), the irradiation figure 48 corresponds to a closed triangle whose dimensions correspond to the triangle of Figure 5c).

[0078] The different strengths with which the triangular contour is shown in Figure 5d) mean that an energy beam parameter characterizing the energy beam 40 is again changed when the irradiation figure 48 is traversed.

[0079] The energy beam parameter can be selected from the group consisting of beam intensity, beam diameter, and travel speed. For example, a relatively thick line represents a relatively high beam intensity, and a relatively thin line represents a relatively low beam intensity. Similarly, a relatively thick line can represent a relatively large beam diameter, and a relatively thin line represents a relatively small beam diameter. Similarly, a relatively thick line can represent a relatively high travel speed, and a relatively thin line represents a relatively low travel speed.

[0080] In the variant of Figure 5e), the irradiation figure 48 corresponds to a spiral line, which also covers a center of the spiral line.

[0081] The variant shown in Figure 5f) shows the irradiation pattern 48 already explained in connection with Figures 1 to 4. This irradiation pattern 48 includes a spiral line, but does not cover the center of the spiral line. The varying intensities with which the spiral line is depicted in Figure 5f) again indicate that an energy beam parameter characterizing the energy beam 40 is changed when traversing the irradiation pattern 48.

[0082] The energy beam parameter can be selected from the group consisting of beam intensity, beam diameter, and travel speed. For example, a relatively thick line represents a relatively high beam intensity, and a relatively thin line represents a relatively low beam intensity. Similarly, a relatively thick line can represent a relatively large beam diameter, and a relatively thin line represents a relatively small beam diameter. Similarly, a relatively thick line can represent a relatively high travel speed, and a relatively thin line represents a relatively low travel speed.

[0083] In Figure 5g), the irradiation pattern 48 is a meander line. Regarding the different line thicknesses, please refer to the previous explanations.

[0084] Figure 5h shows a comparatively complex irradiation pattern 48, which has the shape of a four-leaf clover. This irradiation pattern 48 is composed of numerous curve segments.

[0085] Figure 6 shows further variants by means of which different irradiation figures 48 can be combined to form a macro figure.

[0086] As already mentioned, in the second step S2 of the method, a beam profile 50 is also assigned to each of the irradiation positions PI, P2, P3, P4, P5, P6.

[0087] The powder layer 14 is then irradiated in the third step S3 in the region of the assigned irradiation position PI, P2, P3, P4, P5, P6, wherein the energy beam 40 has the beam profile 50. With multiple irradiation positions PI, P2, P3, P4, P5, P6, the beam profile 50 can therefore differ from irradiation position PI, P2, P3, P4, P5, P6 to irradiation position PI, P2, P3, P4, P5, P6.

[0088] The beam profile 50 can be generated by guiding the energy beam 40 along the planar irradiation pattern 48. In other words, guiding the energy beam 40 along the irradiation pattern 48 results in so-called beam shaping.

[0089] In this context, Figure 7 shows an exemplary beam profile 50 that essentially corresponds to a Gaussian distribution. This beam profile 50 is created with a point exposure, i.e., without beam shaping.

[0090] Figure 7a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 7b) shows a top view of the envelope, looking in the beam direction.

[0091] The energy beam 40 with the beam profile 50 from Figure 7 has a 4sig diameter of 300 pm.

[0092] Figure 8 shows another exemplary beam profile 50 generated by beam shaping. For this purpose, the energy beam 40 was guided along a square irradiation pattern 48. It is understood that the energy beam 40 can be guided along an outer edge of the square irradiation pattern 48 or, alternatively, the square irradiation pattern 48 can be approximated by points representing its corners. In the second case, the corners are irradiated as part of a point exposure.

[0093] Figure 8a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 8b) shows a top view of the envelope, looking in the beam direction.

[0094] In contrast to the example in Figure 7, the energy beam 40 in the example in Figure 8 has a 4sig diameter of 700 pm. Figure 9 shows another example beam profile 50, which was also generated by beam shaping. The beam profile essentially corresponds to a Gaussian distribution.

[0095] In the example of Figure 9, a circular irradiation pattern 48 was used, e.g., the irradiation pattern from Figure 5 a). This pattern was traversed with a defocused energy beam 40. Alternatively, the circular irradiation pattern 48 can also be approximated by a plurality of points, which are then traversed by the energy beam 40.

[0096] As before, Figure 9a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 9b) shows a top view of the envelope, looking in the beam direction. Figure 9c) shows a two-dimensional section through the center of the envelope.

[0097] In contrast to the examples in Figures 7 and 8, the beam profile 50 in Figure 9 is less pointed.

[0098] Another beam profile 50 is shown in Figure 10. The energy beam 40 was moved along a circular line during beam shaping. This means that an irradiation pattern 48 according to Figure 5 a) was also used here. Compared to the beam profile 50 in Figure 9, the energy beam 40 is more strongly focused in the beam profile 50 in Figure 10.

[0099] As before, Figure 10a) shows a three-dimensional view of an envelope of beam profile 50. Figure 10b) shows a top view of the envelope, looking in the beam direction. Figure 10c) shows a two-dimensional section through the center of the envelope.

[0100] This results in a beam profile 50 with a ring-shaped tip.

[0101] Figure 11 shows another beam profile 50, which can be viewed as a variant of the example from Figure 10. The beam profile 50 is also generated by beam shaping, with the energy beam 40 being guided along a planar irradiation pattern 48. The irradiation pattern 48 again comprises a circular line. As before, Figure 11a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 11b) shows a top view of the envelope, looking in the beam direction. Figure 11c) shows a two-dimensional section through the center of the envelope.

[0102] Another example is shown in Figure 12. In this example, the energy beam 40 is moved along a triangle during beam shaping. More precisely, the irradiation pattern 48 is triangular, e.g., as shown in Figure 5 c). The energy beam 40 can be guided continuously along the triangle contour. Alternatively, the triangle can be approximated by points representing its three corners, and these three points can be irradiated.

[0103] As before, Figure 12a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 12b) shows a top view of the envelope, looking in the beam direction. Figure 12c) shows a two-dimensional section through the center of the envelope.

[0104] Another example is shown in Figure 13. In this example, during beam shaping, the energy beam 40 is moved along a circular line approximated by ten individual points. At each of these points, the beam has a 4sig diameter of 300 pm.

[0105] The circular line corresponds to the planar irradiation figure 48 from Figure 5 a).

[0106] As before, Figure 13a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 13b) shows a top view of the envelope, looking in the beam direction.

[0107] The example from Figure 13 can therefore also be imagined as a superposition of ten intensity profiles according to Figure 7. The peak intensity at the points approximating the circular line can be adjusted such that in the example from Figure 7 and in the example from Figure 13, the same amount of energy is introduced into the powder layer by the energy beam 40 in order to produce the component layer 12.

[0108] Another example is shown in Figure 14. In this example, during beam shaping, the energy beam 40 is again moved along a square approximated by four individual points. These points correspond to the corners of the square. At each of these points, the beam has a 4sig diameter of 700 pm.

[0109] The square again represents a flat irradiation figure 48.

[0110] As before, Figure 14a) shows a three-dimensional view of an envelope of the beam profile 50. Figure 14b) shows a top view of the envelope, looking in the beam direction.

[0111] It is understood that, in principle, the use of an irradiation-position-specific, planar irradiation pattern 48 and the use of an irradiation-position-specific beam profile can be carried out independently of one another. This means that a planar irradiation pattern 48 can be used without using an irradiation-position-specific beam profile 50. It is also possible to use an irradiation-position-specific beam profile 50 without using an irradiation-position-specific, planar irradiation pattern 48.

[0112] Of course, an irradiation-position-specific planar irradiation pattern 48 can also be used in combination with an irradiation-position-specific beam profile 50. As explained with reference to the figures, the irradiation-position-specific beam profile 50 can result from traversing the irradiation pattern 48.

[0113] In summary, in all of the examples mentioned, an irradiation-position-specific planar irradiation pattern 48 and / or an irradiation-position-specific beam profile 50 are used for the additive production of the component layer from at least one powder layer. The irradiation-position-specific planar irradiation pattern 48 and / or the irradiation-position-specific beam profile 50 are used during irradiation using an energy beam 40.

[0114] List of reference symbols

[0115] 10 Device

[0116] 12 component layers

[0117] 14 powder layer

[0118] 16 V vacuum chamber

[0119] 18 Construction area

[0120] 20 Wall of the construction area

[0121] 22 Floor slab of the construction area

[0122] 24 lifting units of the construction area

[0123] 26 Powder reservoir

[0124] 28 Wall of the powder reservoir

[0125] 30 Base plate of the powder reservoir

[0126] 32 Lifting unit of the powder reservoir

[0127] 34 squeegees

[0128] 36 Arrow

[0129] 38 Beam generation unit

[0130] 40 Energy Beam

[0131] 42 Deflection unit

[0132] 44 Section of the powder layer

[0133] 46 point grid

[0134] 48 Irradiation figure

[0135] 50 beam profile

[0136] 52 Irradiation path d Position distance

[0137] Pl irradiation position

[0138] P2 Irradiation position P3 Irradiation position

[0139] P4 Irradiation position

[0140] P5 Irradiation position

[0141] P6 Irradiation position SI first step

[0142] 52 second step

[0143] 53 third step

Claims

Patent claims 1. A method for the additive production of a component layer (12) from at least one powder layer (14), comprising: - providing at least one irradiation position (P1, P2, P3, P4, P5, P6) on the powder layer (14) (S1), - Assigning a planar irradiation figure (48) and / or a beam profile (50) to the irradiation position (P1, P2, P3, P4, P5, P6), and - irradiating the powder layer (14) in the region of the irradiation position (P1, P2, P3, P4, P5, P6) by means of an energy beam (40), wherein the energy beam (40) is guided along the planar irradiation figure (48) which is referenced to the irradiation position (P1, P2, P3, P4, P5, P6), and / or wherein the energy beam (40) has the beam profile (50).

2. The method according to claim 1, wherein the irradiation figure (48) comprises a circular line segment, a circular line, an elliptical line segment, an elliptical line, a curved segment, a polygonal segment, a spiral contour and / or a meander line.

3. Method according to claim 1 or 2, wherein the energy beam (40) is guided along the irradiation figure (48) within less than 1 millisecond, preferably within less than 100 microseconds.

4. Method according to one of the preceding claims, wherein the energy beam (40) is guided several times along the planar irradiation figure (48), preferably at a frequency of 500 Hertz or more.

5. Method according to one of the preceding claims, wherein the beam profile (50) of the energy beam (40) is generated by means of beam shaping.

6. Method according to one of the preceding claims, wherein the irradiation position (P1, P2, P3, P4, P5, P6) is defined as a point of a point grid (46) which extends at least in sections over the powder layer (14).

7. Method according to one of the preceding claims, wherein at least one energy beam parameter characterizing the energy beam (40) is changed while the energy beam (40) is guided along the planar irradiation figure (48).

8. The method of claim 7, wherein the at least one energy beam parameter is selected from a group comprising beam intensity, beam diameter, and travel speed.

9. Method according to one of the preceding claims, wherein at least two irradiation positions (PI, P2, P3, P4, P5, P6) are provided on the powder layer (14), wherein each of the at least two irradiation positions (PI, P2, P3, P4, P5, P6) is assigned a planar irradiation figure (48) and / or a beam profile (50), and wherein the powder layer (14) is irradiated in the region of each of the at least two irradiation positions (PI, P2, P3, P4, P5, P6) by means of the energy beam (40), wherein the energy beam (40) is guided along the planar irradiation figures (48) which are referenced to the respectively assigned irradiation position (PI, P2, P3, P4, P5, P6), and / or wherein the energy beam (40) has the respectively assigned beam profile (50).

10. The method according to claim 9, wherein the at least two irradiation positions (P1, P2, P3, P4, P5, P6) are spaced from each other by a positional distance (d), wherein the positional distance (d) is greater than or equal to a melt pool diameter or wherein the positional distance (d) is smaller than a melt pool diameter.

11. The method according to claim 9 or 10, wherein the irradiation figures (48) assigned to the at least two irradiation positions (P1, P2, P3, P4, P5, P6) are connected by means of an irradiation path (52).

12. Method according to one of the preceding claims, wherein the energy beam (40) is pulsed.

13. Method according to one of the preceding claims, wherein the energy beam (40) is an electron beam.

14. The method according to claim 13, wherein the energy beam (40) is guided along the planar irradiation pattern (48) by means of a deflection unit comprising a plurality of magnetic coils, and / or wherein the beam profile (50) is generated by deflecting the energy beam (40) by means of a deflection unit comprising a plurality of magnetic coils.

15. Use of an irradiation-position-specific planar irradiation pattern (48) and / or an irradiation-position-specific beam profile (50) for the additive production of a component layer (12) from at least one powder layer (14) by irradiation with an energy beam (40).

16. Device (10) for the additive production of a component layer (12) from at least one powder layer (14), arranged to carry out a method according to one of claims 1 to 14 to be executed.

17. The device according to claim 16, further comprising a deflection unit with a plurality of magnetic coils for guiding the energy beam along the planar irradiation figure (48) and / or for generating the beam profile (50) by deflecting the energy beam (40).

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