Method for generating build job data for manufacturing components using a powder bed-based melting process, as well as method for manufacturing components using a powder bed-based melting process and computer program

Abstract

Computer-implemented method for generating build job data for manufacturing components (1) using a powder bed-based melting process, comprising the following steps: - Providing model data of components to be produced (1); - Providing a virtual construction space (2) with boundary dimensions (3a, 3b, 3c) which dimension an outer edge of the virtual construction space (2), wherein the virtual construction space (2) represents a real volume space (4) which is filled with powder (5) in which the components (1) to be produced are to be produced; - Creating at least one arrangement pattern (7) by placing and orienting the components (1) to be created on the basis of the model data in the virtual construction space (2); - determining a temperature distribution in the virtual construction space (2) for the arrangement pattern (7), which characterizes an expected temperature distribution of the powder (5) in the real volume space (4); - generating model data of at least one hollow body (9, 17) to be produced, which can be arranged between adjacent components (1, 10, 16) to be produced in the virtual construction space (2) or between at least one component (1, 10, 16) to be produced and the outer edge of the virtual construction space (2), on the basis of the arrangement pattern (7) and the temperature distribution, wherein during the production of the components (1) with the hollow body (9, 17) thermally stressed powder (8) which is located within the hollow body (9, 17) can be encapsulated; - adapting the arrangement pattern (7) on the basis of the at least one hollow body (9, 17) to be produced; - Extracting the construction job data from the adapted layout pattern (7); and - Providing the extracted construction job data.

Description

The invention relates to a computer-implemented method for generating construction job data for producing components using a powder-bed-based melting method.Furthermore, the invention relates to a method for producing components using a powder-bed-based melting method. The invention further relates to a computer program.DE 10 2015 001 480 A1 discloses a method for producing a three-dimensional object by successive consolidation of layers of at least one radiation-curable powdery construction material on a construction panel. At least one delimiting component which at least sectionally images the outer and / or inner contour of the three-dimensional object to be produced is formed by successively consolidating layers of the or at least one powder-like construction material which can be consolidated by means of radiation in order to delimit a construction volume which at least sectionally images the outer and / or inner contour of the three-dimensional object to be produced.DE 10 2011 121 568 A1 discloses a method for producing three-dimensional objects by solidifying a powdery building material by means of laser radiation at the locations corresponding to the respective cross section of the objects. Inside an existing construction chamber, a construction cell is constructed which is closely surrounded by the object to be constructed either by at least one side wall of the construction chamber or by further construction cell wall sections, and the coating volume and the area of the coating application are increasingly simultaneously reduced in such a way that predominantly only the region inside the construction cell is coatedFurthermore, EP 3 695 957 A1 discloses a method for operating an apparatus for producing three-dimensional objects by means of a layered structure.According to an example, in WO 2018 / 118 009 A1, an apparatus may include a memory that may store instructions to cause a processor to generate first level descriptions and second level descriptions for the part for each part to be manufactured in a package space of a 3D manufacturing apparatus. The processor may determine whether there is an arrangement that results in the parts fitting together into the build space using the first level descriptions while providing certain thermal decoupling spaces between the parts. In response to a determination that the layout has not been determined using the first level descriptions for the parts, the processor may determine whether there is a layout that results in the parts fitting together into the packaging space while providing the determined thermal decoupling spaces using the second level descriptions.US 2022 / 0 040 763 A1 discloses a method for defining the construction of a green compact having at least one object embedded therein. The method includes receiving three-dimensional data, defining the at least one object, and identifying a planar surface in the at least one object based on the three-dimensional data. The orientation of the at least one object is defined such that the planar surface extends at least partially across a Z height of the green compact. Per layer, a mask pattern is defined to form the at least one object in the defined orientation by an additive manufacturing method with powder material.US 2022 / 0 288 862 A1 shows a shield connector for circuit board mounting comprising: a contact for circuit board mounting; a housing holding the contact and having a mating opening; a shield sleeve surrounding the housing and having, near a rear end portion, a first circuit board connection portion to be connected to a ground pattern on a circuit board; a casing formed with a plug passage for plugging a mating connector, the plug passage being opened forward and communicating with the mating opening; and a ground member near a front end portion of the casing with a second circuit board connection portion to be connected to the ground pattern on the circuit board.It is an object of the present invention to improve the disposal of thermally excessively heavily loaded loose powders after a manufacturing process of components by means of a powder bed-based melting method.DE 10 2018 112 571 A1 relates generally to methods and apparatuses for additive manufacturing which use compression chambers to reduce pressure on growing objects. In one aspect, the disclosure provides a method of manufacturing an object. The method comprises (a) irradiating a layer of powder in a build area over a build platform to form a fused area; (b) providing a subsequent layer of powder over the build area; and (c) repeating steps (a) and (b) until at least a portion of the object, at least one chamber, and at least one conduit are formed in the build area. The chamber encloses a region of unmelted powder and the conduit extends from a passage within the build platform to the chamber. The method also includes (d) removing unmelted powder from within the chamber via the conduit and the passageway. The disclosure also provides an apparatus for forming compression chambers within an object.WO 2014 206 573 A2 discloses a method for generating a three-dimensional component by selective laser melting, comprising: generating at least one process influencing device by selective laser melting during the generation of the three-dimensional component, and activating the process influencing device for acting on an already completed region of the three-dimensional component before the completion of the three-dimensional component. The invention also relates to a processing machine for carrying out the method.This object is achieved by a computer-implemented method, a method and a computer program according to the independent patent claims. Meaningful further developments are evident from the dependent patent claims.One aspect of the invention relates to a computer-implemented method for generating construction job data for producing components using a powder-bed-based melting method, having the following steps:providing model data of components to be produced;providing a virtual installation space with boundary dimensions which dimension an outer edge of the virtual installation space, wherein the virtual installation space represents a real volume space which is filled with powder in which the components to be produced are to be produced;creating at least one arrangement pattern by placing and orienting the components to be produced on the basis of the model data in the virtual installation space;determining a temperature distribution in the virtual installation space for the arrangement pattern, which characterizes an expected temperature distribution of the powder in the real volume space;generating model data of at least one hollow body to be produced, which can be arranged between adjacent components to be produced in the virtual installation space or between at least one component to be produced and the outer edge of the virtual installation space, on the basis of the arrangement pattern and the temperature distribution, wherein, during the production of the components, thermally loaded powder which is located within the hollow body can be encapsulated with the hollow body;adapting the arrangement pattern on the basis of the at least one hollow body to be produced;extracting the construction job data from the adjusted arrangement pattern; andIn particular, providing the extracted construction job data.By means of the proposed method, construction job data for producing components can be generated or generated in such a way that, during a later production of the components by means of powder-bed-based melting method, thermally excessively heavily stressed powder which remains after the production of the components can be disposed of more easily. In this case, the at least one hollow body is advantageously used, since this hollow body is additionally produced during the production of the components and encloses or encapsulates powder which is subject to excessive thermal stress. Thus, after the production of the components, the at least one hollow body or a plurality of hollow bodies can be removed manually or automatically, so that the powder contained therein can be disposed of. Finally, only the loose powder remains, which can be reused for later production methods with a constant powder quality.With the aid of the method according to the invention, a software tool for a powder bed-based melting method can be provided, with which thermally stressed powder can be encapsulated in order to be able to achieve powder quality maintenance.In the additive manufacturing of plastic components, such as, for example, in the powder-based method, selective laser sintering (SLS) and multijet fusion (MJF), the surrounding unsolidified powder can be reused. This powder may have a thermal stress, so that as a result the powder property can no longer correspond to that of the starting powder. In this case, the thermal load is dependent on the packing density and component arrangement present and on installation space. A decrease in the powder quality due to the thermal load has the result that the component quality can decrease and the reject rate increases. In particular, powder regions which are subjected to severe thermal stress lead to a decrease in the powder quality. In those regions where a high thermal load is present, the hollow body can be provided according to the invention. By means of the hollow body, which can be produced synchronously with the production of the components, encapsulation of the powder that is no longer to be reused later can be carried out.The method according to the invention makes it possible to dispense with a decision made by operating personnel with regard to the disposal of the powder. Up to now, depowdering has been carried out on the basis of experience knowledge, wherein powder amounts are either reused or disposed of depending on the user. This can be remedied by the computer-implemented method. Up to now, there has been no objective procedure or support for the user during depowdering. Such support is now provided by the computer-implemented method or the at least one or more hollow bodies additionally provided. Experience-based depowdering and disposal of powder results in increased material consumption and a lower degree of powder utilization. This can likewise be positively improved by the proposed method. Furthermore, an improvement in the powder quality can be achieved by the proposed method, since an undefined powder quality can be present hitherto by the subjectively embossed decision process when disposing of powder quantities. By encapsulating the powder agent that is too heavily thermally loaded by means of one or more hollow bodies, a constant, in particular high powder quality of the powder to be reused can be achieved.In particular, with the aid of the proposed method, automatic encapsulation of powder regions which are subject to excessive thermal loads and which can then be identified unambiguously by the user and can be disposed of as a closed hollow body. As a result, a subjective decision process and a decrease in the powder quality can be avoided. The homogeneous powder quality can be maintained and powders which are not subject to excessive thermal loads are not reused. In addition, the powder quantities to be disposed of are surrounded by a capsule, i.e. the hollow body, so that the disposal can be considerably improved. By introducing the hollow body, such as a capsule, it is possible to achieve a differentiation of different powder regions, such that, by means of an automated or manual removal of the hollow body, only the powder is still present after the production of the components, which powder can be used with a high quality quality quality in a subsequent production process.The method according to the invention can prevent that powder that is too heavily thermally loaded is reused or that still high-quality powder has already been disposed of. By introducing one hollow body or a plurality of hollow bodies, a separation between powder grades within the installation space can be achieved. As a result, a homogeneous powder quality, a higher degree of powder utilization, low disposal quantities of powder and a defined powder quality, which can have a positive effect on reproducibility of the component properties, can be achieved. On the basis of the arrangement pattern, the components to be produced and the temperature distribution within the virtual installation space, zones or regions can be identified, in particular simulated, which cause a high temperature input to the powder there during a subsequent production process.Powder bed based melting is a category of additive manufacturing processes. In an additive manufacturing process, material is joined, typically layer by layer, to produce workpieces from 3D model data. Methods of this category include manufacturing processes in which thermal energy selectively bonds or fuses regions of a powder bed. The construction job data indicate in particular at which locations the powder is fused. The model data is, for example, computer added design (CAD) data. The delimiting dimensions of the virtual installation space give dimensions of the real volume space. The component is produced in the real volume space.Creating at least one arrangement pattern may be referred to as "Nesting?". Here, for example, a computer-implemented method, such as software, can be used to be able to generate the model data, in particular the arrangement pattern. In the determination of the temperature distribution in the installation space, a calculation or simulation can be carried out, which temperatures are present in the real volume space during the production of the components. The temperature distribution may result from size, orientation, placement, or device characteristics.After the arrangement pattern has been created and thus generated with respect to the components to be produced, it is possible by means of the arrangement and in particular the distribution of the components and the determined temperature distribution to establish or determine in which regions there is an increased introduction of temperature and thus the powder present there can be loaded. In these regions, which are located between adjacent components or between a component and an outer edge of the virtual space, consideration can be taken of the production of the hollow body. Thus, for example, a hollow body filling this intermediate space can be generated between two or more adjacent components. Thus, the powder there, which is likely to be excessively stressed, can be correspondingly encapsulated. In particular, a plurality of hollow bodies can be provided. Subsequently, an adaptation of the arrangement pattern on the basis of the at least one hollow body can again be carried out. Construction job data can thus be extracted accordingly, such that the at least one hollow body can be produced simultaneously or simultaneously during the production of the components.For example, the temperature distribution in the virtual installation space can be calculated by means of a finite element method (FEM) algorithm. Therefore, the temperature distribution can be simulated more easily. A deviation between real temperature values and simulated temperature values can be kept small. For example, the deviation is less than 10%, in particular less than 5%, in particular less than 1%.For example, the temperature distribution can be determined, in particular output, as a function of time for a simulated printing sequence. In other words, the temperature distribution can be determined not only as a function of location, but also as a function of time for the simulated pressure sequence. In the printing sequence, which is also referred to as printing operation, the temperature can change over time. For example, bottom layers that have already been printed cool out over time. By taking into account the time dependence of the printing sequence, a realistic simulation is possible.The inventive device can be used, for example, as a software supplement and / or as an independent software tool for the targeted maintenance of the powder quality with strict separation between powder quality within an installation space. The method according to the invention can be applied to all powder-based, additive manufacturing methods of plastic, metal or ceramic components, such as, for example, "SLS" ("selective laser sintering"), "MJF" ("three-beam material application", "material jetting"), "SLM" ("selective laser melting") or "binder jetting".The method according to the invention makes it possible to avoid subjectively embossed decisions regarding the reuse of powder by objective evaluation. Furthermore, a strict separation between powder grades can be performed. Furthermore, the most varied parameters or target parameters can be preset or determined manually or on the system side during the production and configuration of the hollow body. A specific adjustment of the waste powder quality can be achieved by encapsulation by means of the hollow body. Since a powder that is too heavily loaded can be disposed of accordingly, material efficiency can be achieved. By encapsulating powder to be thermally loaded, other regions can in turn be shielded with powder from the latter, so that a protection of material can be achieved. An increase in component quality and reproducibility can thus be achieved. The encapsulated, in particular loose, powder can easily be disposed of.The computer-implemented method according to the invention can be integrated into existing construction job preparation software. By encapsulating the powder to be disposed of, a reduction in material disposal and material costs can be achieved. Thus, the powder remaining can be used to have a homogeneous powder quality for re-use in later manufacturing processes.In one exemplary embodiment, it is provided that, on the basis of the temperature distribution, a virtual intermediate space which arises between at least the components to be produced in the virtual installation space and between a component to be produced and the outer edge of the virtual installation space is divided into regions for which individual target values of a temperature distribution are predefined. The model data of the at least one hollow body are generated on the basis of the regions; in particular, the hollow body can be arranged within the virtual interspace. In other words, the virtual space may be the space that is not provided with a component. Thus, with regard to the virtual installation space, the entire region within which no installation space is placed or positioned can be used as a virtual intermediate space. Thus, each individual region which extends between components and / or between components and the outer edge can be taken into account in the virtual intermediate space.The virtual intermediate space can in turn be divided into regions, i.e. virtual sub-regions. For this subdivision, an individual target value with regard to a temperature or temperature distribution present there can in turn be provided or predefined for a respective region. This is important because the virtual intermediate region after a later manufacturing process of the components is the region which contains the loose powder which can be reused. By dividing the regions and the individual temperature values, it can thus be established in which of these subareas or regions there is a high temperature input or a high temperature. In these regions, in turn, where an elevated temperature or an elevated temperature input is present, a hollow body can again be placed, since the loose powder located there at the end is likely to be thermally excessively stressed and should be disposed of accordingly.For a respective range, the target value for the temperature of the powder in the respective range can be predefined. In particular, a respective target value for the temperature of the powder in a real intermediate space and the real volume space is to be reached. The specification is carried out, for example, by an operator. It may also be possible for the specification to be effected by a "machine learning algorithm". For this purpose, parameters such as powder and material properties of a printing device can be observed. The target value can be, for example, a temperature maximum value or a specific distribution, which relates, for example, to a homogeneous temperature distribution. If the target value is predefined, for example, for a homogeneous temperature distribution, then the temperature of the powder in the virtual installation space and thus also in the real installation space should be the same.As target value, it can also be set in particular that the intermediate space experiences as homogeneous a temperature load as possible. In other words, not only setting of a quantitative target value but also a qualitative target value is possible. Specifically, the target value is set so as to maximize a quality of the remaining powder. Waste of the powder can thereby be minimized. This achieves a longer use of the used powder and a controlled quality of used powder is present.For example, the virtual installation space can be divided into voxels or voxel groups. In other words, the virtual installation space can be divided into grid points by means of a three-dimensional grid. A grid point may be referred to as a voxel. A plurality of voxels may be combined into a group of voxels. For a single voxel and / or a single voxel group, a specific temperature value can be specified as target value. For example, the aforementioned regions of the virtually subdivided interspace can be voxels of this type.This results in the advantage that individual voxels and / or voxel groups are subjected to higher thermal loads in order to protect other voxels or voxel groups. This can prevent, for example, an amount of powder from being unusable since the thermal load is too high.For example, based on voxels which are located within the interspace and in turn have a high temperature load, it can be taken into account for the creation of the hollow body.For example, after the components have been placed and oriented in the installation space according to the specifications and the laser contours or heating zones are known, a specific classification of the voxels with respect to the expected thermal load of the material can be carried out. In this case, the thermal load can be described by the distance of the voxels or voxel groups from the laser path. The closer the voxels are to the laser paths, the higher the thermal load, so that the powder is to be disposed of there and should be encapsulated by a hollow body. It is also conceivable to take into account the packing density in the installation space, that is to say how many components are placed in the installation space, wherein the packing density can generate a temperature build-up and the powder can therefore be subjected to greater thermal loading. This can in turn be taken into account in the generation of the data of the at least one hollow body or of the plurality of hollow bodies. Voxels and / or voxel groups can be assigned or assigned a specific temperature, i.e. a target value of a temperature distribution, under the already known laser paths and the distance of voxels from the respective laser path resulting therefrom.For example, a subdivision into cold, warm or hot areas can be carried out. It is also conceivable to divide into temperature ranges such as 20 to 100° C., 101 to 150° C., 151 to 170° C., or 171 to 200° C., for example. The higher the temperature input in the divided region, the more heavily loaded the powder there. Furthermore, ranges can be selected depending on the respective melting temperature and crystallization temperature of the material used. A limit value or threshold value can be defined, such as an absolute temperature or an interval from which the voxels or voxel group are automatically surrounded by the hollow body. This can be taken into account in the generation of the model data. For example, the production process of the components by means of a laser, as well as during the production of the components, the respective voxels can be operated with the lasers and thus form the hollow body and enclose the thermally loaded powder contained therein. This hollow body can then be identified and disposed of by a user or an automated device during the later depowdering.In one exemplary embodiment, it is provided that the at least one hollow body is arranged in the virtual intermediate space such that an outer contour of the hollow body bears at least in regions directly spaced apart against the adjacent components to be produced or the outer contour of the hollow body bears at least in regions directly spaced apart against the at least one component to be produced and the outer edge of the virtual installation space. Since a temperature input between the components to be produced or between components and the outer edge is greatest and the powder is highly thermally loaded there, a hollow body is placed or positioned there in each case such that the powder thermally loaded there is at least partially, in particular completely, enclosed or encapsulated by the hollow body. For this purpose, the outer contour of the hollow body can bear directly spaced apart on the components arranged in a surrounding manner. For example, the hollow body can be arranged between two components, and the hollow body can have a minimum distance from the adjacent components in each case on its outer contour. This minimum distance can be specified, for example, by the laser path or by the laser beam. Thus, between two components, the powder that is heavily loaded there can be encapsulated by the hollow body and subsequently disposed of.For example, a laser path for generating the outer contour of the hollow body can be arranged or provided such that this laser path of the hollow body adapts to the contour of the components or to the present thermal load of the powder. Thus, between the hollow body and the contours of the components, the width or the thickness of the laser track is predetermined as a distance. Thus, without waste of installation space, thermally loaded powders loaded as completely as possible can be enclosed there by means of the hollow body.In one exemplary embodiment, it is provided that the at least one hollow body is arranged in the virtual interspace such that the hollow body is at a predefined distance from the adjacent components to be produced, or the hollow body is at a predefined distance from the at least one component to be produced and the outer edge of the virtual installation space. The predefined distance can be predefined, for example, by the laser path and, in particular, by the width of the laser path. As a result, as much thermally stressed powder as possible can be encapsulated by means of the hollow body. However, a minimum distance should be provided between the hollow body and the installation space or the outer edge, since otherwise the hollow body may fuse with the components.In one exemplary embodiment, it is provided that, on the basis of a temperature distribution between the adjacent components to be produced in the virtual installation space or between the at least one component to be produced and the outer edge of the virtual installation space, a wall thickness of the hollow body is adapted and taken into account in generating the model data of the hollow body. As a result, for example, the hollow body can be shielded from the adjacent components. In this case, the wall thickness of the hollow body can be selected independently by a user or automatically generated by a software or a system. For example, the wall thickness range can be between 100 μm and 1000 μm. A wall thickness of, for example, 500 μm is particularly advantageous. In particular, the wall thickness can be made as small as possible in order to avoid additional thermal loading of the surrounding powder. The wall thickness can furthermore be designed to be continuous or variable, which can be carried out, for example, on the system side.The distance of the laser path of the hollow body from the components can be kept as small as possible in order to bind as much thermally heavily loaded powder as possible, i.e. to insert it through the hollow body. For example, a laser path for producing the hollow body and a laser path for producing the components can have a spacing of 100 μm. A connection or a connection between components and the hollow body is to be avoided.In one exemplary embodiment, it is provided that a geometric shape of the hollow body is determined on the basis of a temperature distribution between the adjacent components to be produced in the virtual installation space or between the at least one component to be produced and the outer edge of the virtual installation space and the arrangement pattern, this being taken into account in generating the model data of the hollow body.The shape of the hollow body or the configuration of the hollow body can be carried out or determined such that the thermally loaded powder can be encapsulated or enclosed as completely as possible. For example, the design of the hollow body or of the hollow element can assume predefined bodies, such as a cube, a sphere, a pyramid or some other geometric shape. The design or the shape of the hollow body can likewise be arbitrary and thus freely defined. This can in turn be done by the software.In particular, the configuration of the hollow body takes place as a function of the spread of the thermally excessively heavily loaded powder. A completely undefined contour is likewise conceivable. The outer casing of the hollow body can likewise be smooth or irregular. The outer casing of the hollow body can likewise be rough or provided with a defined haptics. In particular, the hollow body should be designed such that it differs from the components and in particular is designed differently therefrom, such that the hollow body can be easily recognized and correspondingly disposed of.For example, the shape can be specified on the system side or manually. Laser parameters, i.e. of the laser for melting the powder with which the hollow body is produced, can either correspond to the parameters with which the components are produced or can be freely selected.It is also conceivable that the parameters are not designed for the highest possible component quality, but rather are designed for the fastest possible, low-quality surface quality of the hollow body. As a result, the energy input or the effort for producing the hollow body can be kept low, since the hollow body is separated out later and is not used for applications like the components.Furthermore, a laser speed can be minimized and the laser intensity can be minimized for producing the hollow body. It is also conceivable that the outer contour line of the hollow body requires a high surface quality in order to avoid connecting to other components and to achieve the smallest possible laser path distance between hollow body and components. Accordingly, the inner contours, i.e. those directed toward the thermally loaded powder, can be manufactured to be less high-quality. Furthermore, it is conceivable that the hollow body is provided on its outer surface with a marking, for example a letter or a symbol, in order to be able to unambiguously identify or mark the hollow body as a part to be disposed of. Markings can likewise be generated by melting the powder by means of a laser.A further possibility for generating the model data for the hollow body is taking into account the regions or voxels. For example, it can be established from which cluster of voxels which are subject to thermal loads that voxel should be automatically bound by the hollow body. It would be conceivable that, for a powder quantity of more than one gram, which is classified as heavily loaded powder, it should be surrounded automatically by the hollow body.Powder which is used for the contour of the hollow body can be assigned either to the powder which is subject to excessive thermal stress or to the powder which can theoretically be reused. This can be done by the user or by software. The software or a computer program which is used for implementing the computer-implemented method can be used as independent software during construction job preparation or as a supplement to existing software tools for construction job preparation. It must be taken into account in the construction job data to be generated that the hollow body surrounds only loose powder, but no components to be produced.In one exemplary embodiment, it is provided that construction data, in particular CAD data, are provided as construction job data, which specify at which points in the powder thermal energy is introduced by a directed energy source in each case for an applied powder layer, in order to selectively connect or fuse the powder at these points. The energy source may be a laser.For example, real temperatures can be monitored during the printing process. For example, the temperature is measured by means of optical temperature sensors. The measured temperature values can be provided as input parameters to the machine learning algorithm. This makes it possible to check whether the ascertained temperature distribution corresponds to the measured temperature values. Furthermore, the specification of the individual temperature targets can be improved.A further aspect of the invention relates to a method for producing components using a powder-bed-based melting method, having the following steps:applying a powder as a powder bed to a support;selectively thermally acting on the powder by means of a directional energy source in dependence on the construction job data produced according to a method of the preceding claims;removing the powder; andsupplying reusable powder that is part of the removed powder for a next production cycle;This achieves a powder-saving production method which makes efficient use of the powder. The waste powder can be significantly reduced. The components can also be produced with precision in shape. In particular, the density of components which are produced during the process is also increased as a result.The powder is applied as a powder board to a support as a function of the construction job data. The construction job data are determined and provided in particular according to the method mentioned above. The removal of the powder can be referred to as "depodering". In particular, the removed powder can be reused. The quality and quantity of this reusable powder is intended to improve the method for generating the construction job data.In particular, the loose powder, which is not a thermal load, can be removed. Likewise, the powder, which is too heavily loaded, can be realized by removing or by removing the hollow body.A further aspect of the invention relates to a computer program comprising instructions which, when the program is executed by a computer, cause the computer to execute a method according to the preceding aspects and an advantageous development, and which can be loaded in a memory unit and can be executed by a processor. In particular, the computer-implemented method mentioned at the beginning can be used with the computer program just mentioned for generating construction job data.For use cases or application situations which can arise in the method and which are not explicitly described here, provision can be made for an error message and / or a request for inputting a user feedback to be output and / or for a default setting and / or a predetermined initial state to be set according to the method.The invention also includes developments of the system according to the invention and of the computer program according to the invention, which have features as have already been described in connection with the developments of the method according to the invention. For this reason, the corresponding developments of the system according to the invention and of the computer program according to the invention are not described again here.The invention also includes the combinations of the features of the described embodiments.Embodiments of the invention will be described below. The following shows: FIG. 1 shows a schematic flow diagram of an exemplary embodiment for generating construction job data for producing components; FIG. 2 shows a schematic plan view of a real volume space with components and hollow bodies to be produced; FIG. 3 shows a schematic illustration of a virtual installation space with a hollow body arranged between two components; FIG. 4 shows a further schematic embodiment of an arrangement of components and hollow bodies in the virtual installation space; FIG. 5 shows an exemplary detailed illustration of the virtual installation space from FIG. 4 ; FIG. 6 shows a schematic illustration of a square hollow body; FIG. 7 shows a schematic sectional illustration of the hollow body from FIG. 6 ; FIG. 8 is a schematic illustration of a hollow body in a cylindrical form; FIG. 9 shows a schematic sectional illustration of the hollow body from FIG. 8 ; FIG. 10 shows a further possible embodiment of the hollow body; FIG. 11 shows a schematic sectional illustration of the hollow body from FIG. 10 ; FIG. 12 shows a further embodiment of the hollow body with an inner opening or an inner region; and FIG. 13 shows a schematic sectional illustration of the hollow body from FIG. 12.The exemplary embodiments explained below are preferred exemplary embodiments of the invention. In the exemplary embodiments, the described components each represent individual features of the invention that are to be considered independently of one another and that develop the invention in each case also independently of one another and are therefore also to be considered as part of the invention individually or in a combination other than the combination shown. Furthermore, the described exemplary embodiments can also be supplemented by further features of the invention that have already been described.In the figures, elements having the same function are each provided with the same reference numerals.FIG. 1 shows a schematic flow diagram of an exemplary embodiment of a method according to the invention or of a simulation method for generating construction job data for producing components using a powder bed-based melting method.In an optional step S 1, model data of components 1 to be generated (compare FIG. 2 ) can be provided. This model data can be provided, for example, as CAD data. In a subsequent optional step S 2, a virtual installation space 2 (compare FIG. 3 ) with delimiting dimensions 3 a, 3 b, 3 c(compare FIG. 3 ) can be provided. The delimiting dimensions 3 a, 3 b, 3 cmay dimension an outer edge of the virtual installation space 2. The virtual installation space 2 can represent a real volume space 4 (compare FIG. 2 ). The real volume space 4 can be virtually filled with powder 5 (compare FIG. 2 ). The components 1 to be produced can be produced in and with the powder 5.For example, a target value for a temperature for a virtual interspace 6 (compare FIG. 3 ) can be predefined. The virtual intermediate space 6 can arise between the components 1 to be produced in the virtual installation space 2 and between a component 1 to be produced and the outer edge of the virtual installation space 2.In a further step S 3, at least one arrangement pattern 7 (compare FIG. 3 ) can be created by placing and orienting the components 1 to be produced on the basis of the model data in the virtual installation space 2, in particular depending on the target value.In a further optional step S 4, a temperature distribution in the virtual installation space 2 for the arrangement pattern 7 can be determined. The temperature distribution can characterize an expected temperature distribution of the powder 5 in the real volume space 4.Based on the temperature distribution, for example, a zone definition, such as cold or hot zones, can be carried out. For this purpose, in an optional fifth step S 5, parameters for component production, such as laser speed, laser intensity, heating zones or layer thicknesses, can be provided.During the production of the components 1, a temperature input can be exerted into powder 5 which is loose around the components 1. This introduction of temperature can result in this powder being so heavily loaded, in particular thermally loaded, that it can no longer be reused for later production processes. For this purpose, this thermally stressed powder 8 (compare FIG. 2 ) can be encapsulated or enclosed by means of a hollow body 9. This can in turn take place in an optional step S 6. In this case, model data of the hollow body 9 or of a plurality of hollow bodies can be generated. This hollow body can be arranged between adjacent components 10 to be produced (compare FIG. 2 ). It is likewise conceivable for the hollow body 9 to be arranged between at least one component 1 and the outer edge of the virtual installation space 2. For the generation of this model data, the arrangement pattern 7 and the temperature distribution can be taken into account. When manufacturing the components 1, the hollow body 9 can be produced synchronously, so that the thermally stressed powder 8 can be encapsulated in this hollow body. After the production of the components 1, the thermally stressed powder 8 can be removed again by removing the hollow body 9, so that this is not reused.Since the at least one hollow body 9 could be generated in particular only after the arrangement pattern 7 has been generated, an adaptation of the arrangement pattern 7 can take place after the generation of the model data of the hollow body 9.With regard to the determination of the hollow body 9, in an optional step S 7, parameters or input variables which can be used for the production or for the use of a hollow body 9 can be provided. In order to establish which regions have an increased temperature entry, the virtual installation space 2 can be divided or divided into voxels 11 and / or into voxel groups 12. For example, the voxel 11 is cuboidal, in particular cubic, volume units within the virtual installation space 2. A plurality of voxels 11 may form, for example, a voxel group 12. For each of these voxels, a temperature or temperature distribution there can be simulated or predefined. Regions or zones can thus be detected or established which have a high temperature and accordingly have thermally stressed powder 8. In this step S 7, a wall thickness 13 (compare FIG. 2 ), which the hollow body 9 should have, can be specified, for example, as a parameter. Likewise, a set of voxels 11 and / or a voxel group 12 can be predetermined. If a temperature threshold value has been reached and / or exceeded within adjacent voxels 11, these voxels 11 can be encapsulated automatically by means of at least the hollow body 9. A laser speed and / or laser intensity of a laser can likewise be provided. A design, a configuration and / or a geometric shape of the hollow body 9 can likewise be predetermined or defined. Likewise, a distance between components 1 and laser paths 15 can be predefined. The laser path 15 is a contour of the laser 14 for melting the powder, in particular for producing the components 1.In an optional step S 8, the construction job data can be extracted and in particular provided on the basis of the adapted arrangement patterns 7.FIG. 2 shows an example of a volume space 4. In this case, it can be seen on the one hand how the three components 10 are arranged in such a way that an intermediate space is formed which can have powder 8 which is under too high a thermal load and this is encapsulated by means of the hollow body 9. Furthermore, the components 16 are positioned very close to one another, so that a hollow body 17 is likewise arranged therebetween at least in regions.The arrangement pattern 7 is a possibility of how the components 1 to be produced can be placed and oriented within the virtual installation space 2. In this case, it may be necessary in particular for framework conditions to be able to be fulfilled. Possible boundary conditions are, for example, that the components 1 to be produced must not overlap and / or a minimum distance between the components 1 to be produced must be maintained between one another and / or to the outer edges of the virtual installation space 2 and / or a minimum number of components 1 to be produced must be placed within the virtual installation space 2.On the basis of the extracted construction job data, the components 1 can be produced in a real production method by means of a system 17 or a printing device, which in turn can be the laser or laser device. The components 1 can be produced by powder bed-based melting. In particular, at least one powder layer can be applied for this purpose. This can then be heated locally by means of the laser 14 or a thermal energy source. The heated powder 4 then melts. The next powder layer can then be applied. On the basis of the adapted arrangement pattern 7 and in particular the hollow bodies 9, 17, it is possible for the thermally stressed powder 8, which was not required for producing the components 1, to be correspondingly reacted or encapsulated in order to be able to subsequently dispose of it. Furthermore, regions such as region 18 may again be present, which may contain thermally unloaded powder due to the distances from the components 1. This can in turn be reused for later manufacturing processes.As already mentioned, FIG. 3 shows a schematic illustration of the virtual installation space 2. In this case, the virtual intermediate space 6, within which no component or no hollow body is located, is illustrated by way of example. In this case, two components 1 are arranged one above the other, and the hollow body 9 with the powder 8 that is under excessively high thermal load is located therebetween.FIG. 4 shows a further exemplary illustration of the virtual installation space 2. A sectional illustration is shown here. In this case, a plurality of components 1 are arranged close to one another. A plurality of hollow bodies 9 are provided in the regions between the components 1, since the close arrangement of the components 1 results in the powder lying therebetween being subjected to too high thermal loads and having to be disposed of after the production process of the components 1.In FIG. 5, again starting from FIG. 1, a detailed illustration or a section can be seen. The hollow body 9 can be seen between two components 1 and the thermally loaded powder 8 contained therein. A predefined distance 23 may be present or defined between the hollow body 9 and the components 1. In particular, the hollow body 9 should not touch with any component 1.The hollow body 9 or the encapsulation can have a wide variety of geometric configurations in cross section. The shape is, for example, a square, a circle, a rectangle, a triangle or a stepped shape. In particular, any desired shape is conceivable. The hollow body 9 can be rotationally symmetrical or completely randomly or arbitrarily. It can likewise be translation-symmetrical.FIG. 6 shows an exemplary illustration of the hollow body 9 in the form of a cuboid. For this purpose, a sectional illustration is again shown in FIG. 7, so that the hollow body 9 and the thermally stressed powder 8 contained therein are disposed around it.FIG. 8 again shows the hollow body 9 as a cylinder. For this purpose, a sectional illustration is again shown in FIG. 9, where the powder 8 contained in the cavity can be seen.FIG. 10 again shows an random or shape-free geometry of the hollow body 9. In particular, depending on the configuration of the arrangement pattern 7 and in particular the arrangement of the components 1 and the temperature distribution, the shape can be adapted as desired. FIG. 11 again shows a section relating to the illustration from FIG. 10.FIG. 12 shows a further conceivable configuration of the hollow body 9. In this case, the hollow body 9 can have an inner opening. In this opening 24 or in this inner region, powder can again be located which has undergone a less intense introduction of temperature. As can be seen in FIG. 13, which shows a sectional illustration of the hollow body 9 shown in FIG. 12, the thermally loaded powder 8 is located between the outer contour of the hollow body 9 and the opening 24. Thus, depending on the configuration of the construction job data and in particular depending on the circumstances or the production of parts by means of a melting method, the shape or configuration of the hollow body 9 can be adapted or varied as desired. Thus, depending on the manufacturing situation or application, it can be ensured that powder 8 that is thermally under excessively severe load is not used in further processing steps. This is achieved by the encapsulation of this powder 8 by means of the hollow body 9.List of reference characters1 Components 2 Virtual installation space 3 Boundary dimensions 4 Real volume space 5 Powder 6 Virtual interspace 7 Arrangement pattern 8 Thermally loaded powder 9 Hollow body 10 Components 11 Voxels 12 Voxel group 13 Wall thickness 14 Laser 15 Laser path 16 Component 17 Hollow body 18 Region 19 System 20 Memory unit 21 Evaluation unit 22 Output unit 23 Distance 24 Opening S 1 to S 8 Steps

Claims

Computer-implemented method for generating construction job data for producing components (1) using a powder-bed-based melting method, having the following steps: - providing model data of components (1) to be produced; - providing a virtual installation space (2) having delimiting dimensions (3a, 3b, 3c) which dimension an outer edge of the virtual installation space (2), wherein the virtual installation space (2) represents a real volume space (4) which is filled with powder (5) in which the components (1) to be produced are to be produced; - creating at least one arrangement pattern (7) by placing and orienting the components (1) to be produced on the basis of the model data in the virtual installation space (2); determining a temperature distribution in the virtual installation space (2) for the arrangement pattern (7) which characterizes an expected temperature distribution of the powder (5) in the real volume space (4); generating model data of at least one hollow body (9, 17) to be produced, which can be arranged between adjacent components (1, 10, 16) to be produced in the virtual installation space (2) or between at least one component (1, 10, 16) to be produced and the outer edge of the virtual installation space (2), on the basis of the arrangement pattern (7) and the temperature distribution, wherein, during the production of the components (1) with the hollow body (9, 17), thermally loaded powder (8) which is located within the hollow body (9, 17) can be encapsulated; adapting the arrangement pattern (7) on the basis of the at least one hollow body (9, 17) to be produced; extracting the construction job data from the adjusted arrangement pattern (7); and providing the extracted construction job data.Method according to Claim 1, wherein, on the basis of the temperature distribution, a virtual intermediate space (6) which arises between at least the components (1) to be produced in the virtual installation space (2) and between a component (1) to be produced and the outer edge of the virtual installation space (2) is divided into regions (11, 12) for which individual target values of a temperature distribution are predefined, wherein the model data of the at least one hollow body (9, 17) are generated on the basis of the regions (11, 12), in particular the hollow body (9) is arranged within the virtual intermediate space (6).Method according to claim 2, wherein the at least one hollow body (9, 17) is arranged in the virtual intermediate space (6) such that - an outer contour of the hollow body (9, 17) abuts at least in regions directly spaced apart on the adjacent components (1, 10, 16) to be produced, or - the outer contour of the hollow body (9, 17) abuts at least in regions directly spaced apart on the at least one component (1) to be produced and the outer edge of the virtual installation space (2).Method according to claim 2 or 3, wherein the at least one hollow body (9, 17) is arranged in the virtual intermediate space (6) such that - the hollow body (9, 17) has a predefined distance (23) from the adjacent components (1, 10, 16) to be produced, or - the hollow body (9, 17) has a predefined distance (23) from the at least one component (1) to be produced and the outer edge of the virtual installation space.Method according to one of the preceding claims, wherein a wall thickness (13) of the hollow body (9, 17) is adapted on the basis of a temperature distribution between the adjacent components (1, 10, 16) to be produced in the virtual installation space (2) or between the at least one component (1) to be produced and the outer edge of the virtual installation space (2) and is taken into account in generating the model data of the hollow body (9, 17).Method according to one of the preceding claims, wherein a geometric shape of the hollow body (9, 17) is determined on the basis of a temperature distribution between the adjacent components (1, 10, 16) to be produced in the virtual installation space (2) or between the at least one component (1) to be produced and the outer edge of the virtual installation space (2) and the arrangement pattern (7), wherein this is taken into account in the generation of the model data of the hollow body (9, 17).Method according to one of the preceding claims, wherein construction data, in particular CAD data, are provided as construction job data, which design data specify at which points in the powder (5) thermal energy is introduced in each case for an applied powder layer by a directed energy source (14) in order to selectively bond or fuse the powder (5) at these points.Method for producing components (1) with a powder bed-based melting method, comprising the following steps: - applying a powder (5) as a powder bed to a support; - selectively thermally acting on the powder (5) by means of a directed energy source (14) depending on the construction job data generated according to a method of the preceding claims; - removing the powder (5); and - supplying reusable powder (5) which is part of the removed powder (5) for a next production cycle;A computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method of any one of claims 1 to 7, and which is loadable into a memory unit (20) and executable by a processor.

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