Method for producing a three-dimensional object

Abstract

Method for producing a three-dimensional object (2), comprising the steps: - Specification of a reference object information describing geometric-constructive data of a reference object, wherein the geometric-constructive design of the reference object is defined with regard to an object-specific application or field of use, as well as at least one boundary condition information describing at least one geometric-constructive boundary condition of the object (2) to be manufactured, wherein corresponding geometric-constructive data of the reference object described by the reference object information describe a basic form of the object actually to be manufactured that is to be modified or optimized, - Determining load information describing at least one load value in a specific load situation within the reference object described by the reference object information by means of a computer-based simulation, - Determination of load ranges with load values ​​deviating from a reference load value within the reference object described by the reference object information using the load information by means of a computer-based simulation, - Determining object information describing geometric-constructive data of the three-dimensional object (2) to be manufactured on the basis of the load information and the boundary condition information, - producing the three-dimensional object (2) to be produced on the basis of the object information, wherein the three-dimensional object (2) to be produced is generatively produced at least in load ranges with load values ​​deviating from the reference load value by successively selectively solidifying a solidifiable building material (3) in layers, wherein the three-dimensional object (2) to be produced is produced in load ranges with load values ​​deviating from the reference load value with a tempering channel structure which is generatively formed by successively selectively solidifying the solidifiable building material (3) in layers by means of the energy beam (5) generated by the radiation generating device (4), and through which a tempering medium can flow for tempering the produced three-dimensional object (2).

Description

[0001] The invention relates to a method for producing a three-dimensional object.

[0002] Methods for producing three-dimensional objects, such as technical articles, are known in the state of the art in a variety of different designs.

[0003] Processes for the additive manufacturing of three-dimensional objects are becoming increasingly important. Three-dimensional objects are constructed by successively and selectively solidifying a solidifiable building material layer by layer in the respective cross-sectional areas of the respective objects to be manufactured, using an energy beam generated by a radiation generation device.

[0004] The geometric design, especially the weight, of three-dimensional objects manufactured using known processes is generally determined by geometric design data specified prior to the actual production. Optimization of the geometric design of the respective object, for example, based on the loads actually acting on the manufactured object in an object-specific application or field of use, is typically not performed within the scope of such processes.

[0005] The prior art includes the documents US 2015 / 0 003 995 A1, EP 2 586 548 A1, DE 10 2012 005 276 A1, DE 10 2013 220 983 A1, EP 2 875 928 A1 and DE 10 2013 212 803 A1.

[0006] The invention is based on the object of providing an improved method for producing a three-dimensional object.

[0007] This object is achieved by a method according to claim 1. The dependent claims relate to advantageous embodiments of the method. The object is further achieved by a device according to the independent claim 14.

[0008] The method described herein generally serves to produce three-dimensional objects (hereinafter referred to as "objects"). The objects to be produced or produced by the method are or are at least partially constructed or produced generatively. An object produced by the method can therefore comprise conventionally, i.e., non-generatively constructed, object sections and generatively constructed object sections. Of course, an object produced by the method can also be completely constructed or produced generatively, so that it comprises exclusively generatively constructed object sections.

[0009] The generative construction or generative production of a corresponding object or object section is based on a successive, selective, layer-by-layer solidification of at least one solidifiable building material in respective cross-sectional areas of the respective object or object section to be produced, by means of at least one energy beam generated by at least one radiation generation device. The successive, selective, layer-by-layer solidification of the solidifiable building material is carried out on the basis of construction data describing the geometric-constructive shape, i.e. in particular the layer-related cross-sectional geometries, of the respective object or object section to be produced. Corresponding construction data generally describe the geometric or geometric-constructive shape of the respective object or object section to be produced.

[0010] A solidifiable construction material used in the process can be, for example, a metal powder (mixture) that can be solidified by means of a corresponding energy beam and / or a plastic powder (mixture) that can be solidified by means of a corresponding energy beam. Such a solidifiable construction material is typically powder-like or powder-form.

[0011] An energy beam used within the process can be electromagnetic radiation, i.e. a laser beam, or laser for short. A radiation generation device used within the process can then be a laser generation device for generating a laser beam. In this case, the process can comprise, for example, a selective laser sintering process, or SLS process for short, for carrying out selective laser sintering processes for the generative production of three-dimensional objects, or a selective laser melting process, or SLM process for short, for carrying out selective laser melting processes for the generative production of three-dimensional objects. Within the process, electron or particle radiation can also be used instead of electromagnetic radiation. A radiation generation device used within the process is then an electron orParticle generation device for generating an electron or particle beam.

[0012] The method generally comprises the method steps defined in claim 1.

[0013] In a first step of the method, reference object information describing geometric-constructive data of a reference object and at least one boundary condition information describing at least one geometric-constructive boundary condition of the object actually to be produced by means of the method are created or specified.

[0014] The reference object information describes data of a reference object. Corresponding data includes, in particular, a defined geometric-structural design, i.e., in particular, a defined outer contour, of the reference object. The reference object information thus describes, in particular, the geometric-structural design of the reference object. The reference object information can therefore describe design data, e.g., computer-aided design (CAD) data, of the reference object. The reference object typically represents an object whose type corresponds to the object to be manufactured. If, as explained below by way of example, a tool element of an injection mold is manufactured within the scope of the method, for example, the reference object already represents a tool element of an injection mold.

[0015] The geometric design, in particular the mass, of the reference object is typically defined with regard to an object-specific application or use area. Corresponding geometric design data of the reference object described by the reference object information contain a basic shape, typically generic, of the object actually to be manufactured, which is to be subsequently modified or optimized. The geometric design of the reference object described by the reference object information therefore differs from the geometric design of the object to be manufactured, and vice versa.Certain geometric and structural parameters of the object to be manufactured may therefore correspond to certain geometric and structural parameters of the reference object, while other geometric and structural parameters of the object to be manufactured may differ from certain geometric and structural parameters of the reference object. Of course, it is also possible that all geometric and structural parameters of the object to be manufactured may differ from the geometric and structural parameters of the reference object.

[0016] Specifically, reference object information can, for example, describe a solid reference object with defined external dimensions or a defined external contour. The external dimensions or the external contour, i.e. (essentially) the external shape, of the object to be manufactured deviates, as will become apparent below, at least in sections, possibly completely, from the external dimensions or the external contour, i.e. (essentially) the external shape, of the reference object due to the process. If the external shape of the object to be manufactured does not deviate completely from the external shape of the reference object, the external dimensions or the external contour, i.e. (essentially) the external shape, of the object to be manufactured can correspond at least in sections to the external dimensions or the external contour, i.e. (essentially) the external shape, of the reference object.

[0017] In addition to the reference object information, as mentioned, at least one piece of boundary condition information is also created or specified. This boundary condition information describes various boundary conditions relating to the object to be manufactured. Boundary conditions can be geometric-design parameters or structural-physical parameters or properties of the object to be manufactured. The boundary condition information can thus be used to specify certain geometric-design parameters or certain structural-physical parameters or properties that must (mandatorily) be present in at least one section of the object to be manufactured or in the entire object to be manufactured.

[0018] Corresponding boundary conditions can define at least one geometric-structural parameter of at least one outer (exposed) object section of the object to be manufactured, e.g., a surface, a side surface, a bottom surface, etc., and / or at least one inner (non-exposed) object section of the object to be manufactured, or geometric-structural parameters of the entire object to be manufactured. Typically, corresponding geometric-structural parameters define at least the outer dimensions or the outer contour, i.e., (essentially) the outer shape, of at least one object section of the object to be manufactured or of the entire object to be manufactured.

[0019] Corresponding boundary conditions can alternatively or additionally define at least one structural-physical parameter of at least one outer (exposed) object section of the object to be manufactured and / or at least one inner (non-exposed) object section of the object to be manufactured or at least one structural-physical parameter of the entire object to be manufactured. Corresponding structural-physical parameters are in particular mechanical parameters, such as mass, density, hardness, strength or flexural strength, stiffness or flexural rigidity, elasticity, plasticity (ductility), toughness, and / or tribological parameters, such as friction coefficient, wear resistance, and / or optical-acoustic parameters, such as light and / or sound absorption or light and / or sound reflection, and / or thermal parameters, such asthermal expansion, thermal conductivity, (specific) heat capacity, hot strength, cold toughness, and / or electrical parameters, such as electrical conductivity, electrical resistance, of at least one section of the object to be manufactured or of the entire object to be manufactured.

[0020] Examples of specific boundary condition information are given below: For example, boundary condition information can describe at least one two- or three-dimensional region of the object to be manufactured that cannot be changed with respect to the geometric-structural data of the reference object described by the reference object information. The object to be manufactured can then be manufactured with a region corresponding to the unchangeable region described by the boundary condition information. The geometric-structural design of the object corresponds, at least to this extent, to the geometric-structural design of the reference object.

[0021] Boundary condition information can also describe a closed outer contour of the object to be manufactured. The object to be manufactured can then be manufactured with a closed outer contour corresponding to the closed outer contour described by the boundary condition information. The geometric design of the object corresponds, at least to this extent, to the geometric design of the reference object.

[0022] A piece of boundary condition information can further describe at least one solid outer and / or inner region of the object to be manufactured. The object to be manufactured can then be manufactured with a solid outer and / or inner region corresponding to the solid outer and / or inner region described by the boundary condition information. The geometric design of the object corresponds, at least to this extent, to the geometric design of the reference object.

[0023] A piece of boundary condition information can further describe at least one object-specific functional element with regard to the intended use of the object to be manufactured, e.g., a connecting region or a connecting element for connecting the object to another object. The object to be manufactured can be manufactured with a functional element corresponding to the at least one functional element described by the boundary condition information. The geometric design of the object corresponds, at least to this extent, to the geometric design of the reference object. In this way, it can be ensured that the manufactured object can be connected to other objects as intended, i.e., in particular, can also be inserted into other objects.

[0024] In a second step of the method following the first step, load information describing at least one load value in at least one specific load situation, in particular at least one load situation when the object to be manufactured is used as intended, is determined within the reference object described by the reference object information. The load information therefore describes load values ​​which at least one reference object section or the entire reference object experiences in specific load situations, and thus the behavior (“load behavior”) of at least one reference object section or the entire reference object in specific load situations. Corresponding load situations can, for example, be intended load scenarios of the object to be manufactured, i.e. load situations to which the object to be manufactured is typically exposed when used as intended.Of course, it is also possible that the corresponding load situations are load scenarios generated independently of the intended use of the object to be manufactured.

[0025] The load information can generally describe a mechanical and / or climatic and / or fluidic and / or thermal load situation, particularly during intended use of the object to be manufactured. A corresponding load situation can also include a distribution of the respective loads within the object, at least in sections.

[0026] The load information is generated using suitable algorithms through a computer-based simulation, e.g., a finite element method (FEM). In other words, the load information can include data from a simulation, e.g., an FEM simulation.

[0027] In a third step of the method following the second step, load ranges with load values ​​that deviate from a predefinable or predefined reference load value within the reference object described by the reference object information are determined on the basis of the load information or in the load information. The load values ​​determined in the second step of the method within the at least one reference object section or within the entire reference object in the respective load situation under consideration are thus compared individually, in groups, or as a whole with at least one reference load value. In particular, it is thus determined by comparison whether corresponding load values ​​within the at least one reference object section or within the entire reference object are above or below a corresponding reference load value, and thus whether they exceed or fall below a corresponding reference load value.A reference load value can be understood as an upper and / or lower load limit. Upper and lower load limits are typically defined by object-specific, particularly material-specific, parameters.

[0028] The determination of corresponding load ranges with load values ​​deviating from a reference load value within the reference object described by the reference object information based on the load information or in the load information is carried out by suitable algorithms using a computer-based simulation, e.g., a FEM simulation.

[0029] In a fourth step of the method following the third step, object information describing the geometric-structural data of the object to be manufactured is determined on the basis of the load information and the boundary condition information. Corresponding geometric-structural data contain, in particular, the geometric-structural design of the object to be manufactured. The object information therefore describes, in particular, the geometric-structural design of the object to be manufactured. The geometric-structural design of the object to be manufactured includes boundary conditions described by the boundary condition information, i.e., geometric-structural parameters that must be provided on the object to be manufactured, such as a mandatory geometric-structural external design of the object, and / or structural-physical parameters that must be provided on the object to be manufactured, such asmandatory mechanical properties of the object, a maximum weight of the object, etc. Likewise, the load values ​​described by the load information are included in the object information.

[0030] The object information can therefore describe design data, e.g., CAD data, of the object to be manufactured. This design data is typically converted into construction data describing the geometric-constructive shape, i.e., in particular, the layer-related cross-sectional geometries, of the respective object or object section to be manufactured.

[0031] In a fifth step of the process following the fourth step, the object to be manufactured is produced based on the object information. The object to be manufactured is produced additively, at least in the load ranges with load values ​​that deviate from the reference load value, by successive, selective, layer-by-layer solidification of a solidifiable building material. At least those areas of the object to be manufactured or manufactured that correspond to the determined load ranges of the reference object, in which load values ​​deviate from the corresponding reference load values, i.e., in which they are below or exceed them, are thus constructed additively. Of course, as mentioned, the entire object can also be constructed additively.

[0032] By generatively constructing at least certain areas of the object to be manufactured or manufactured, which correspond to the load ranges of the reference object in which load values ​​deviate from the corresponding reference load values, special external and / or internal structures can be formed in these generatively constructed areas of the object, which take into account the respective deviation of the respective load values ​​from the corresponding reference load values. This principle is illustrated by the following examples: In areas of the object that correspond to the corresponding load ranges of the reference object that would fall below certain mechanical reference load values, e.g., lower limits such as a minimum stiffness, generatively targeted structures can be formed that result in (local) mechanical reinforcement, e.g., mechanical stiffening of the object. In areas of the object that correspond to the corresponding load ranges of the reference object that already exceed certain mechanical reference load values, e.g., upper limits, generatively targeted structures can be formed that result in, e.g., a (local) weight or material reduction (compared to a solid construction of the object).

[0033] In areas of the object that correspond to the corresponding load ranges of the reference object that would exceed certain thermal reference load values, e.g., upper limits such as a maximum operating temperature, targeted temperature control channel structures can be generatively formed that allow (local) temperature control, in this case cooling, of the object. In areas of the object that correspond to the corresponding load ranges of the reference object that would fall below certain thermal reference load values, e.g., lower limits such as a minimum operating temperature, targeted temperature control channel structures can be generatively formed that allow (local) temperature control, in this case heating, of the object.

[0034] The examples show a particular advantage of the method, which enables specific object sections or the entire object to be manufactured using generative means, i.e., in particular with generatively formed structures, in particular with regard to specific load situations of the object. The construction of respective object sections or the object is based on the prior determination of specific load areas in the reference object, which, as described, were evaluated with regard to specific reference load values, i.e., compared with corresponding reference load values. In this way, with regard to a specific load situation, areas can be determined which are specially designed with regard to the specific load situation, i.e., e.g., with special structures, i.e., in particular, optimized. As mentioned, this can include, for example,a formation of mechanical reinforcement structures and / or a formation of mechanical weakening structures, e.g. weight or material saving structures and / or a formation of temperature control channel structures, etc.

[0035] The object to be manufactured can thus be optimized for a specific application or load situation, which significantly improves the structural properties of the object under various aspects, e.g., mechanical stability, weight, etc. In particular, it is possible for such optimization to occur only in the interior of the object. The external dimensions or outer contour, i.e. (essentially) the external shape, of the object can be retained (compared to the reference object).

[0036] A further advantage of the process is that three-dimensional objects manufactured using this method can be constructed entirely using additive manufacturing. Particularly with regard to the production of technical objects, i.e., tool elements for injection molding tools, such as tool insert elements, slide elements, etc., which previously comprised a basic object body kept in a warehouse, which is then provided with at least one object section constructed using additive manufacturing on the basic object body ("hybrid object"), storage space, storage time, warehouse work, etc., can be saved through the direct additive manufacturing of the object.

[0037] A further advantage of the process is the possibility of economical use of resources, especially building materials. This allows for a good or even improved energy balance of the process (“CO2 footprint”).

[0038] The above-mentioned procedural steps, or individual steps, may be carried out directly one after the other. It is also conceivable that the procedural steps, or individual steps, may be carried out indirectly, i.e., with the interposition of other procedural steps and / or interruptions of the process.

[0039] One embodiment of the method provides that the object to be manufactured is produced in load ranges with load values ​​deviating from the reference load value with a lightweight structure comprising at least one lightweight construction element, which is generatively formed by successive, selective layer-by-layer solidification of the solidifiable construction material by means of the energy beam generated by the radiation generation device. Through the targeted generative formation of corresponding lightweight structures, the object can be specifically manufactured with generatively formed structures in areas corresponding to load ranges of the reference object that exceed or fall below certain reference load values. These structures bring about a reduction in weight or material, e.g., through a (local) density reduction. Lightweight structures are typically formed in areas of the object that are subject to little mechanical stress.Through the generative formation of corresponding lightweight structures, these can be formed in any geometric-constructive configuration, in particular cross-sectional geometries, and can extend arbitrarily through the object.

[0040] A lightweight construction element of a corresponding lightweight structure can be, for example, a recess, a sandwich structure, a region with a lower density compared to other regions of the manufactured object, a region made of a solidifiable construction material with a lower density compared to other solidifiable construction materials of the manufactured object, or a region with a smaller wall thickness compared to other regions of the manufactured object. A corresponding sandwich structure typically consists of at least one layer of lower mechanical stability arranged or formed between at least two layers of higher mechanical stability. The layer of lower mechanical stability can, for example, be cellular.

[0041] According to the invention, the object to be manufactured is produced in load ranges with load values ​​deviating from the reference load value with a tempering channel structure generatively formed by successive, selective, layer-by-layer solidification of the solidifiable construction material by means of the energy beam generated by the radiation generation device, through which a tempering medium, generally a tempering fluid (gas and / or liquid), can flow to temper the manufactured object. A tempering channel structure comprises at least one tempering channel extending at least partially through at least one object section.Through the targeted generative formation of corresponding temperature control channel structures, the object can be specifically manufactured with generatively formed structures in areas that correspond to corresponding (thermal) load ranges of the reference object, which exceed or fall below certain (thermal) reference load values, through which a temperature control medium flows, thereby temperature controlling the object. Temperature control channel structures are typically formed in thermally stressed areas of the object. Using appropriate temperature control channel structures, targeted temperature control, i.e. cooling or heating, of specific sections of the object or of the entire object can be achieved. Through the generative formation of corresponding temperature control channel structures, these can be formed in any geometric-structural configuration, in particular cross-sectional geometries, and can extend arbitrarily, for example in a meandering manner, through the object.

[0042] A further embodiment of the method provides that the object to be manufactured is produced in load ranges with load values ​​deviating from the reference load value with a stiffening structure comprising at least one stiffening element, which is generatively formed by successive, selective layer-by-layer solidification of the solidifiable building material by means of the energy beam generated by the radiation generation device. Through the targeted generative formation of corresponding stiffening structures, generally corresponding structures for increasing the mechanical stability of the object, the object can be specifically manufactured with generatively formed structures in regions that correspond to corresponding (mechanical) load ranges of the reference object that exceed or fall below certain (mechanical) reference load values, which, for example, through (local) stiffening, increase the mechanical stability of the object.Stiffening structures are typically formed in mechanically stressed areas of the object. Through the generative formation of corresponding stiffening structures, these can be formed in any geometrical configuration, especially cross-sectional geometries, and can extend freely through the object.

[0043] A ribbing element, for example, can be used as a stiffening component. A stiffening structure can be formed, for example, as two- or three-dimensional longitudinal and / or transverse ribbing.

[0044] In general, generatively formed structures, i.e. in particular lightweight structures and / or temperature control channel structures and / or stiffening structures and / or bionic structures, can extend two- or three-dimensionally, optionally in a network-like manner, through at least one section of the object or the entire object. Such generatively formed structures can extend (only) through the interior of the object, so that they are not visible from the outside. In addition to their respective original function, such structures can of course also influence (other) structural-physical properties of the object. This can be the case, for example, with a rib structure, possibly three-dimensional, within the object, which on the one hand requires a reduction in material (compared to a solid formation) and on the other hand requires mechanical stiffening of the object.

[0045] Of course, corresponding lightweight structures can be combined as desired with corresponding temperature control channel structures and / or with corresponding stiffening structures.

[0046] A further embodiment of the method provides that the object to be produced is produced in load ranges with load values ​​deviating from the reference load value with a bionic structure comprising at least one bionic element which describes at least one biological, in particular animal and / or plant, structure and / or is derived from at least one biological, in particular animal and / or plant, structure and which is generatively formed by successive selective layer-by-layer solidification of the solidifiable building material by means of the energy beam generated by the radiation generation device.

[0047] Within the framework of the process, specific "biological models" that have proven themselves in nature under identical, similar, or comparable load conditions can be selected with regard to specific property or load requirements of the object to be manufactured. These models can be modified if necessary, e.g., with regard to specific property or load requirements of an object to be manufactured, and then generatively formed in the respective object to be manufactured or manufactured. These, possibly modified, "biological models" are described by bionic data. The bionic data thus describe biological structures and / or structures derived from biological structures.

[0048] The bionic data can be linked to other construction data of the respective object to be manufactured, which other construction data do not describe biological structures, so that the construction data underlying the successive, selective, layer-by-layer solidification of the respective solidifiable building material (also) contains bionic data. The structures described in the respective bionic data can thus be formed in the respective object to be manufactured, at least in a modified form.

[0049] The structures described by the bionic data typically serve as construction elements and enable the targeted influencing or adjustment of certain properties of an object to be manufactured, particularly with regard to specific property or load requirements. In other words, by forming corresponding biological structures or structures derived from corresponding biological structures in an object to be manufactured or produced, certain properties of the object to be manufactured or produced can be tailored, specifically influenced or adjusted, particularly with regard to specific property or load requirements. By forming corresponding biological structures or structures derived from corresponding biological structures in an object to be manufactured or producedFor example, the mechanical and / or thermal and / or fluidic properties or the mechanical and / or thermal stability of at least one area of ​​an object to be manufactured or manufactured can be specifically influenced or adjusted.

[0050] Biological structures derived from or modified from corresponding biological structures are structures which do not faithfully depict a biological model, but rather are at least partially modified. An example of a biological structure in this context would be the skeleton of a bird's wing, which has individual skeletal elements, i.e. in particular bones, in a certain number, arrangement, orientation, etc. with certain geometric dimensions. A modification of this biological structure would be, for example, a change in the number and / or arrangement and / or orientation and / or the geometric dimensions of at least one skeletal element. The same naturally applies to all biological structures described by corresponding bionic data.

[0051] Biological structures can be animal and / or animal-derived structures and / or plant structures and / or plant-derived structures. Biological structures can also be structures derived from or modified by animal and / or animal-derived structures and / or plant and / or plant-derived structures. In principle, it is also conceivable that bionic data describe human structures and / or structures derived from human structures. In this context, however, it should be noted that the bionic data are only a part of the corresponding construction data, so that the construction data are typically not used as a basis for the generative production of objects that are identical replicas of human structures, e.g., for dental prostheses.

[0052] Corresponding bionic data can, as mentioned, describe animal structures. In general, external and / or internal animal structures, in particular tissue structures and / or armor structures and / or skeletal structures and / or surface structures and / or cellular structures, can be used as animal structures. Animal structures can therefore be, for example, external and / or internal armor structures and / or skeletal structures of an animal or part of an animal. In this context, reference is made by way of example to certain extremities or limbs or parts of certain extremities or limbs of a specific animal. A concrete example is the skeleton of a bird's wing, which has particular mechanical properties due to a specific number, arrangement, alignment, and formation of certain bone structures. Animal structures can also be surface structures of an animal.In this context, reference is made to specific fur, plumage, scale, or skin structures of a particular animal. A specific example is the scale structure of a shark, which, due to the specific arrangement and formation of individual scales, exhibits, among other things, special aerodynamic properties.

[0053] Corresponding bionic data can also describe animal-derived structures. In general, external and / or internal structures of an animal-derived object, e.g., an animal-derived building and / or an animal-derived textile, in particular a woven or net-like textile, can be used as animal-derived structures. In this context, reference is made to specific animal-derived structures or parts of specific animal-derived structures by way of example.A concrete example is a web structure modeled on a spider web structure produced by spiders, a thread structure modeled on a silk thread structure produced by silkworms, a building structure modeled on a termite structure produced by termites or a honeycomb structure modeled on a honeycomb structure produced by bees, each of which has particular mechanical and / or (particularly for the example of a termite structure, which typically has a specific ventilation or cooling channel structure) flow-related properties.

[0054] Corresponding bionic data can also describe plant structures. In general, external and / or internal plant structures, in particular tissue structures and / or plant skeletal structures and / or surface structures and / or cell structures, can be used as plant structures. In this context, reference is made by way of example to specific plant structures or plant structure extensions or parts of specific plant structures or plant structure extensions. A concrete example is a branch or leaf structure of a specific plant, which has special mechanical properties due to a specific arrangement and formation of specific rib structures, i.e. a main rib extending in the longitudinal direction of the branch or leaf and lateral ribs branching off from it. Plant structures can, as mentioned, also be surface structures of a plant.In this context, reference is made to specific surfaces of a leaf or stem structure of a particular plant. A specific example is the recreation of the surface structure of a lotus leaf, which, due to a specific micro- or nanostructuring, exhibits special properties that prevent the adhesion of dirt particles and are water-repellent.

[0055] Corresponding bionic data can also describe plant-derived structures. In general, plant-derived structures can be defined as external and / or internal structures of a plant-derived object, e.g., a plant-derived fruit. Examples in this context refer to plant-derived structures or parts of specific plant-derived structures. A specific example is a fibrous or textile structure modeled on a fibrous or textile structure produced by flax or hemp plants, which exhibits special mechanical properties.

[0056] Of course, corresponding bionic data can describe different animal structures and / or plant structures or different animal-produced structures and / or plant-produced structures.

[0057] Of course, the aforementioned structures, ie lightweight structures, temperature control channel structures, stiffening structures, can be formed generatively on the basis of corresponding bionic data.

[0058] A concrete example of an object that can be produced or is to be produced using the method is a tool element of an injection mold, in particular a slide element or a tool insert element. Thus, for example, a corresponding tool element of an injection mold can be produced using the method.

[0059] The invention further relates to a device for the additive production of a three-dimensional object by selectively solidifying a solidifiable building material layer by layer using an energy beam generated by a radiation generating device. The device is designed to carry out the method described above. All statements relating to the method therefore apply analogously to the device.

[0060] The invention is explained in more detail using exemplary embodiments in the drawing figures. In the drawings: Fig. 1 shows a schematic diagram of an apparatus for carrying out a method according to an embodiment of the invention; and Fig. 2 - 7 each show a schematic diagram of a method step of a method according to an embodiment of the invention.

[0061] Fig. Figure 1 shows a schematic diagram of a device 1 for carrying out a method according to an embodiment of the invention. The device 1, and thus the method that can be carried out with it, serves for the additive production of a three-dimensional object 2, i.e., typically a technical component or a group of technical components, by successively and selectively solidifying a solidifiable building material 3 layer by layer by means of an energy beam 5 generated by a radiation generation device 4.

[0062] The successive selective layer-by-layer solidification of the solidifiable building material 3 is carried out in such a way that the energy beam 5 generated by the radiation generating device 4 is directed via a beam deflection device 6 in a targeted manner onto specific areas to be solidified, corresponding to the respective layer-related cross-sectional geometries of the object 2 to be produced, of a building material layer formed by means of a coating device 7 which is movably mounted, as indicated by the horizontally oriented arrow, in a building chamber 8 of the device 1.

[0063] The layer-by-layer selective solidification of the solidifiable building material 3 and thus the generative construction of the object 2 takes place on a support device with a carrier mounted for vertical movement. The carrier is mounted for movement relative to the radiation generation device 4, for example.

[0064] The energy beam 5 used is electromagnetic radiation, i.e., a laser beam, or laser for short. The radiation generation device 4 used is therefore a laser generation device for generating a laser beam. The method can therefore be a selective laser sintering method, or SLS method for short, for carrying out selective laser sintering processes for the additive production of three-dimensional objects 2, or a selective laser melting method, or SLM method for short, for carrying out selective laser melting processes for the additive production of three-dimensional objects 2.

[0065] The solidifiable building material 3 used can be, for example, a metal powder (mixture) that can be solidified by means of the energy beam 5, i.e., for example, an aluminum or steel powder, and / or a plastic powder (mixture) that can be solidified by means of the energy beam 5, i.e., for example, a polyetheretherketone powder.

[0066] Of course, in addition to the above-mentioned functional components, ie the radiation generating device 4, the beam deflection device 6 and the coating device 7, the device 1 has further functional components not shown - since they are not essential for the explanation of the principle described herein - which are typically necessary or expedient for carrying out generative construction processes.

[0067] The layer-by-layer selective solidification of the solidifiable building material 3 is carried out based on construction data. The construction data generally describe the geometric or geometric-constructive shape of the object 2 to be produced additively. The construction data are stored in at least one control device (not shown) associated with the device 1, which controls the respective additive construction process or the functional components of the device 1 required for the respective additive construction process.

[0068] An embodiment of the method, in which an object 2 in the form of a tool slide element for an injection molding tool is produced, is described with reference to Fig. 2 - 7 are explained in more detail.

[0069] In the first step of the process, a data of a Fig. 2, and at least one boundary condition information describing, in particular, a geometric-constructive boundary condition of the object 2 actually to be produced by the method is created or specified. The reference object information describes data of the reference object.

[0070] Corresponding data contains a defined geometric-structural design, i.e., in particular, a defined outer contour, of the reference object. The reference object information thus describes the geometric-structural design of the reference object, i.e., in particular, design data, e.g., CAD data, of the reference object. The geometric-structural design, i.e., in particular, also the mass, of the reference object is typically defined with regard to an object-specific application or area of ​​use.

[0071] In addition to the reference object information, as mentioned, boundary condition information is also created or specified. The boundary condition information describes various boundary conditions relating to the object 2 to be manufactured. Boundary conditions can be geometric-constructive parameters or structural-physical parameters or properties of the object 2 to be manufactured. The boundary condition information thus specifies certain geometric-constructive parameters or certain structural-physical parameters or properties that must (mandatorily) be present in at least one section of the object 2 to be manufactured or in the entire object 2 to be manufactured.

[0072] Corresponding boundary conditions define at least one geometric-constructive parameter of at least one outer (exposed) object section of the object 2 to be manufactured, e.g., a surface, a side surface, a bottom surface, etc., and / or at least one inner (non-exposed) object section of the object 2 to be manufactured, or geometric-constructive parameters of the entire object 2 to be manufactured.

[0073] Corresponding boundary conditions can alternatively or additionally define at least one structural or physical parameter of at least one outer (exposed) object section of the object 2 to be manufactured and / or at least one inner (non-exposed) object section of the object 2 to be manufactured or at least one structural or physical parameter of the entire object to be manufactured. Corresponding structural or physical parameters are in particular mechanical parameters, such as mass, density, hardness, strength or flexural strength, stiffness or flexural rigidity, elasticity, plasticity (ductility), toughness, and / or tribological parameters, such as friction coefficient, wear resistance, and / or optical-acoustic parameters, such as light and / or sound absorption or light and / or sound reflection, and / or thermal parameters, such asthermal expansion, thermal conductivity, (specific) heat capacity, hot strength, cold toughness, and / or electrical parameters, such as electrical conductivity, electrical resistance, of at least one section of the object to be manufactured or of the entire object to be manufactured 2.

[0074] The boundary condition information can, for example, describe or define two- or three-dimensional regions of the object 2 to be manufactured that are not to be changed or cannot be modified, with regard to the geometric-constructive data of the reference object described by the reference object information. Object 2 is then manufactured with regions corresponding to the non-modifiable regions described by the boundary condition information.

[0075] The boundary condition information can, for example, describe or define a closed outer contour of the object 2 to be manufactured. The object 2 is then manufactured with a closed outer contour corresponding to the closed outer contour described by the boundary condition information.

[0076] The boundary condition information can further describe or define, for example, solid outer and / or inner regions of the object 2 to be manufactured. The object 2 is then manufactured with the solid outer and / or inner regions corresponding to the solid outer and / or inner regions described by the boundary condition information.

[0077] The boundary condition information can further describe or define at least one object-specific functional area or element with regard to the intended use of the object 2 to be manufactured, e.g., a connection area or a connection element for connecting the object 2 to another object. The object 2 is then manufactured with a functional area or element corresponding to the at least one functional area or element described by the boundary condition information.

[0078] In the Fig. 2 - 7, the boundary condition information particularly describes or defines that (i) a front tip 9 (in Fig. 2 on the corresponding object sections of the reference object) of the object 2 must be formed at least contiguously with the object sections 10, 11, (ii) the geometric-structural design of the object section 11 must be retained, (iii) the (exposed) outer surfaces of the object 2 must be closed and (iv) the object 2 must not be shortened in its geometric-structural design compared to the reference object. The boundary condition information further defines that (v) the object 2 should be manufactured in such a way that mechanical loads acting on it during intended use, in particular as compressive loads, are absorbed, (vi) the region of the tip 9 of the object 2 must be provided with a conformal cooling channel structure and (vii) all object sections not required for the cooling of the object 2, in particular bores, may be removed.

[0079] In a second step of the method following the first step, load information describing at least one load value in at least one specific load situation within the reference object described by the reference object information is determined (cf. Fig. 3). The load information describes load values ​​experienced by at least one reference object section or the entire reference object in specific load situations, and thus the behavior ("load behavior") of at least one reference object section or the entire reference object in specific load situations. Such load situations are, for example, intended load scenarios of the object 2 to be manufactured, i.e., load situations to which the object 2 to be manufactured is typically exposed during its intended use.

[0080] The load information can generally describe a mechanical and / or climatic and / or fluidic and / or thermal load situation, particularly during intended use of the object 2 to be manufactured. The load information is created using suitable algorithms by means of a computer-based simulation, e.g., a FEM simulation. In other words, the load information contains data from a simulation, e.g., a FEM simulation, cf. Fig. 3.

[0081] Based on Fig. 3 shows that only a small portion of the reference object is mechanically loaded under the given mechanical load situation. Fig. 3 can be estimated insofar as a comparatively high potential for reducing building material and thus a comparatively high potential for reducing the weight of object 2 is possible.

[0082] In a third step of the method following the second step, load ranges with load values ​​within the reference object that deviate from a predeterminable or predefined reference load value are determined based on the load information or in the load information. The load values ​​determined in the second step of the method within the reference object in the respective load situation under consideration are then compared individually, in groups, or as a whole with at least one reference load value. It is then determined by comparison whether corresponding load values ​​within the reference object are above or below a corresponding reference load value. A reference load value can be understood as an upper and / or lower load limit value. Upper and lower load limit values ​​are typically defined by object-specific, in particular material-specific, characteristics.

[0083] The determination of corresponding load ranges with load values ​​deviating from a reference load value within the reference object based on the load information or in the load information is carried out by suitable algorithms using a computer-based simulation, e.g., a FEM simulation.

[0084] In Fig. Figure 4 shows a FEM simulation of the geometric design of the reference object after adaptation to the load situation. The different hatchings indicate different loads. Fig. A corresponding CAD model is shown in Figure 5. The geometric and structural design of the reference object is clearly visible in comparison to the Fig. 2 shown has changed significantly. While this approach allows for a significant reduction in weight and material, the aforementioned constraints are not met.

[0085] In a fourth step of the method following the third step, object information describing the geometric and structural data of the object 2 to be manufactured is determined based on the load information and the boundary condition information. The corresponding geometric and structural data contain the geometric and structural design of the object 2 to be manufactured, cf. Fig. 6. The geometrical and structural design of the object 2 to be manufactured incorporates the boundary conditions described or defined by the boundary condition information. Likewise, the load values ​​described by the load information are incorporated into the object information.

[0086] Based on Fig. 6 shows that the object information describes design data, e.g., CAD data, of the object 2 to be manufactured. These design data are converted into construction data describing the geometric-constructive shape, ie, in particular, the layer-related cross-sectional geometries, of the object 2 to be manufactured.

[0087] Based on Fig. 6 it can also be seen that in respective areas of the object 2 to be manufactured, which correspond to the load areas of the reference object in which load values ​​deviate from corresponding reference load values, special generatively constructed external and / or internal structures are formed, which take into account the respective deviation of the respective load values ​​from corresponding reference load values.

[0088] In a fifth step of the method following the fourth step, object 2 is manufactured based on the object information. Object 2 is manufactured additively, at least in the load ranges with load values ​​that deviate from the reference load value, by successively selectively solidifying a solidifiable building material in layers. In the exemplary embodiment, the entire object 2 is constructed additively.

[0089] The object 2 is manufactured in load ranges with load values ​​that deviate from the reference load value using a generatively formed lightweight structure 12 comprising at least one lightweight construction element. Through the targeted generative formation of the lightweight structure 12, the object 2 is specifically manufactured in areas that correspond to corresponding load ranges of the reference object that exceed or fall below certain reference load values ​​using generatively formed structures that bring about a reduction in weight or material through a (local) density reduction. The lightweight structure 12 is formed in areas of the object 2 that are subject to little mechanical stress. As a lightweight construction element of a corresponding lightweight structure 12, for example,a recess, a sandwich structure, a region with a lower density compared to other regions of the manufactured object 2, a region made of a solidifiable building material 3 having a lower density compared to other solidifiable building material 3 of the manufactured object 2 or a region with a lower wall thickness compared to other regions of the manufactured object 2.

[0090] The object 2 is manufactured in load areas with load values ​​that deviate from the reference load value using a generatively formed tempering channel structure (not shown), through which a tempering medium can flow to temper the manufactured object 2. Through the targeted generative formation of corresponding tempering channel structures, the object 2 can be specifically manufactured in areas that correspond to corresponding (thermal) load areas of the reference object that exceed or fall below certain (thermal) reference load values, with generatively formed structures through which a tempering medium flows to temper the object 2. Tempering channel structures are typically formed in thermally stressed areas of the object 2. Targeted tempering, i.e. cooling or heating, of the object 2 can be realized using corresponding tempering channel structures.

[0091] The object 2 is manufactured in load ranges with load values ​​that deviate from the reference load value with a generatively formed stiffening structure 13 comprising at least one stiffening element. Through the targeted generative formation of the stiffening structure 13, the object 2 can be specifically manufactured with generatively formed structures in areas that correspond to corresponding (mechanical) load ranges of the reference object that exceed or fall below certain (mechanical) reference load values, which increase the mechanical stability of the object 2 through (local) stiffening. A ribbing element, for example, can be formed as a stiffening component, cf. Fig. 6. The stiffening structure 13 can be formed with three-dimensional longitudinal and / or transverse ribbing.

[0092] The object 2 can be manufactured in load ranges with load values ​​that deviate from the reference load value using a generatively formed bionic structure (not shown) comprising at least one bionic element that describes at least one biological, in particular animal and / or plant, structure and / or is derived from at least one biological, in particular animal and / or plant, structure. The bionic element can be an animal structure, with external and / or internal animal structures and / or animal-produced structures being used as animal structures, and / or a plant structure, with external and / or internal plant structures and / or plant-produced structures being used as plant structures.

[0093] Generatively formed structures, i.e. in particular lightweight structures 12 and / or temperature control channel structures and / or stiffening structures 13 and / or bionic structures, can extend two- or three-dimensionally, optionally in a network-like manner, through the object 2. Corresponding generatively formed structures can extend (only) through the interior of the object 2, so that they are not visible from the outside. In addition to their respective original function, corresponding structures can of course also influence (other) physical properties of the object 2. This can be the case, for example, with a possibly three-dimensional rib structure within the object 2, which on the one hand requires a reduction in material (compared to a solid formation) and on the other hand requires a mechanical stiffening of the object 2.

[0094] The method makes it possible to produce object 2, particularly with regard to certain load situations of object 2, in a targeted generative manner, i.e. in particular with generatively formed structures. The construction of object 2 is based on the prior determination of certain load regions in the reference object which, as described, were evaluated with regard to certain reference load values, i.e. compared with corresponding reference load values. In this way, with reference to a specific load situation, regions can be determined which are to be specially formed with regard to the specific load situation, i.e. e.g. with special structures, i.e. in particular optimized. As mentioned, this can be understood as e.g. the formation of mechanical reinforcement structures and / or the formation of mechanical weakening structures, i.e. e.g. weight or material saving structures and / or the formation of temperature control channel structures, etc.

[0095] Object 2 is thus optimized with regard to a specific application situation or a specific load situation, which significantly improves the structural properties of object 2 under various aspects, e.g., mechanical stability, weight, etc. In particular, it is possible for such optimization to occur only in the interior of object 2. The external dimensions or the external contour, i.e. (essentially) the external shape, of object 2 can be retained (compared to the reference object).

[0096] A further advantage of the method is that objects 2 to be manufactured according to the method can be constructed entirely additively. Particularly with regard to the production of technical objects, i.e., tool elements for injection molding tools, such as tool insert elements, slide elements, etc., which until now comprised a basic object body kept in a warehouse, which is then provided with at least one object section generatively constructed on the basic object body ("hybrid object"), storage space, storage time, warehouse work, etc. can be saved through the direct additive production of object 2.

[0097] Fig. Finally, Figure 7 shows a representation of a FEM simulation of the object 2 to be manufactured or manufactured based on the object information. The different hatchings indicate different loads. It can be seen that a supporting structure of object 2 is loaded in a similar way as in the Fig. 4. The lightweight structure 12 is largely unloaded. However, the lightweight structure 12 is useful for absorbing certain loads arising during the operation of the object 2, e.g., when the object 2 is clamped in a clamping fixture.

[0098] With the Fig. In the exemplary embodiment explained in Figures 2-7, the weight of object 2 could be reduced by more than 50% compared to the (solid) reference object, while maintaining the same geometric design and functionality. By adapting certain boundary conditions, a further reduction in the weight of object 2 could be achieved. LIST OF REFERENCE SYMBOLS 1 device 2 objects 3 Building materials 4 Radiation generating device 5 Energy Beam 6 Beam deflection device 7 Coating device 8 Construction chamber 9 top 10 Object section 11 Object section 12 Lightweight structure 13 Stiffening structure

Claims

[1] Method for producing a three-dimensional object (2), comprising the steps: - Specification of a reference object information describing geometric-constructive data of a reference object, wherein the geometric-constructive design of the reference object is defined with regard to an object-specific application or field of use, as well as at least one boundary condition information describing at least one geometric-constructive boundary condition of the object (2) to be manufactured, wherein corresponding geometric-constructive data of the reference object described by the reference object information describe a basic form of the object actually to be manufactured that is to be modified or optimized, - Determining load information describing at least one load value in a specific load situation within the reference object described by the reference object information by means of a computer-based simulation, - Determination of load ranges with load values ​​deviating from a reference load value within the reference object described by the reference object information using the load information by means of a computer-based simulation, - Determining object information describing geometric-constructive data of the three-dimensional object (2) to be manufactured on the basis of the load information and the boundary condition information, - producing the three-dimensional object (2) to be produced on the basis of the object information, wherein the three-dimensional object (2) to be produced is generatively produced at least in load ranges with load values ​​deviating from the reference load value by successively selectively solidifying a solidifiable building material (3) in layers, wherein the three-dimensional object (2) to be produced is produced in load ranges with load values ​​deviating from the reference load value with a tempering channel structure which is generatively formed by successively selectively solidifying the solidifiable building material (3) in layers by means of the energy beam (5) generated by the radiation generating device (4), and through which a tempering medium can flow for tempering the produced three-dimensional object (2). [2] Method according to claim 1, characterized bythat the three-dimensional object (2) to be produced is produced in load ranges with load values ​​deviating from the reference load value with a lightweight structure (12) comprising at least one lightweight construction element, which is generatively formed by successive selective layer-by-layer solidification of the solidifiable building material (3) by means of the energy beam (5) generated by the radiation generation device (4). [3] Method according to claim 2, characterized bythat a recess, a sandwich structure, a region with a lower density compared to other regions of the manufactured three-dimensional object (2), a region made of a solidifiable building material (3) having a lower density compared to another solidifiable building material (3) of the manufactured three-dimensional object (2), or a region with a lower wall thickness compared to other regions of the manufactured three-dimensional object (2) is formed as a lightweight construction element. [4] Method according to one of the preceding claims, characterized bythat the three-dimensional object (2) to be produced is produced in load ranges with load values ​​deviating from the reference load value with a stiffening structure (13) comprising at least one stiffening element, which is generatively formed by successive selective layer-by-layer solidification of the solidifiable building material (3) by means of the energy beam (5) generated by the radiation generating device (4). [5] Method according to claim 4, characterized by that a ribbing element is formed as a stiffening component. [6] Method according to one of the preceding claims, characterized bythat the three-dimensional object (2) to be produced is produced in load ranges with load values ​​deviating from the reference load value with a bionic structure which is generatively formed by successive selective layer-by-layer solidification of the solidifiable building material (3) by means of the energy beam (5) generated by the radiation generation device (4) and comprises at least one bionic element which describes at least one biological structure and / or is derived from at least one biological structure. [7] Method according to claim 6, characterized bythat an animal structure is formed as the bionic element, wherein external and / or internal animal structures and / or animal-produced structures are used as the animal structures, and / or a plant structure is formed as the bionic element, wherein external and / or internal plant structures and / or plant-produced structures are used as the plant structures. [8] Method according to one of the preceding claims, characterized by that the boundary condition information describes at least one region of the three-dimensional object (2) to be produced which cannot be changed with regard to geometric-constructive data of the reference object described by the reference object information, and the three-dimensional object (2) to be produced is produced with a region corresponding to the non-changeable region described by the boundary condition information. [9] Method according to one of the preceding claims, characterized by that the boundary condition information describes an at least partially closed outer contour of the three-dimensional object (2) to be produced and the three-dimensional object (2) to be produced is produced with an at least partially closed outer contour corresponding to the at least partially closed outer contour described by the boundary condition information. [10] Method according to one of the preceding claims, characterized by that the boundary condition information describes at least one solid outer and / or inner region of the three-dimensional object (2) to be produced and the three-dimensional object (2) to be produced is produced with a solid outer and / or inner region corresponding to the solid outer and / or inner region described by the boundary condition information. [11] Method according to one of the preceding claims, characterized bythat the boundary condition information describes at least one object-specific functional element with regard to a proper use of the three-dimensional object (2) to be produced, wherein the three-dimensional object (2) to be produced is produced with a functional element corresponding to the at least one functional element described by the boundary condition information. [12] Method according to one of the preceding claims, characterized by that the load information describes a mechanical and / or climatic and / or fluidic and / or thermal load situation. [13] Method according to one of the preceding claims, characterized by that a tool element of an injection molding tool is produced as the three-dimensional object (2) to be produced. [14] Device (1) for the generative production of a three-dimensional object (2) by successive layer-by-layer selective solidification of a solidifiable building material (3) by means of an energy beam (5) generated by a radiation generating device (4), characterized by that the device (1) is designed to carry out the method according to one of the preceding claims.

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