WO2020173519A1

WO2020173519A1 - Layering process and layering apparatus for the additive production of at least one component region of a component, and computer program product and storage medium

Info

Publication number: WO2020173519A1
Application number: PCT/DE2020/000034
Authority: WO
Inventors: Alexander Ladewig; Sebastian Rott; Katrin Friedberger; Steffen Schlothauer
Original assignee: MTU Aero Engines AG
Priority date: 2019-02-26
Filing date: 2020-02-24
Publication date: 2020-09-03
Also published as: DE102019219327A1

Abstract

The invention relates to a layering process for the additive production of at least one component region (12) of a component (14), in particular a component (14) of a turbomachine. The layering process comprises at least the steps: a) providing at least one reference monitoring data set (50), which is based on reference false colour values (64) detected by optical tomography of at least one reference component region (60) of a reference component (62) during the adaptive production thereof and characterizes local intensity maxima (66) of the reference false colour values (64); b) applying at least one powder layer of a material (22) to at least one structure and a joining zone (II) of at least one movable construction platform (24); c) locally solidifying the material (22) to form a component layer by the material (22) being scanned selectively along scanning lines (40) with at least one beam of energy (28) and being melted, wherein at least one exposure parameter value of the beam of energy (28) is adjusted according to the at least one reference monitoring data set (50) and, as a result, according to at least one of the local intensity maxima (66), d) lowering the construction platform (24) layer by layer by a predefined layer thickness, and e) repeating the steps b) to d) until the component region (12) is completed. The invention also relates to a layering apparatus (10) for the additive production of at least one component region (12) of a component (14), to a computer program product, to a computer-readable storage medium, and to a component (14) having at least one additively produced component region (12).

Description

Layer construction method and layer construction device for the additive manufacture of at least one construction part area of a component as well as computer program product and storage medium

description

The invention relates to a layer construction method and a layer construction device for the additive production of at least one component region of a component. The invention further relates to a computer program product, a computer-readable storage medium and a component with at least one additively manufactured component area.

Additive layer construction processes describe processes in which geometric data are determined based on a virtual model of a component or component area to be manufactured, which is broken down into layer data (so-called "slicing"). Depending on the geometry of the model, an exposure or irradiation strategy is determined according to which the selective solidification of a material is to take place. In the layer construction process, the desired material is then deposited in layers and selectively scanned and solidified by means of the at least one energy beam in order to additively build up the desired component area. Various irradiation parameters such as the energy beam power and the exposure speed of an energy beam to be used for solidification are important for the resulting microstructure. The arrangement of so-called scan lines is also important. The scan lines, which can also be referred to as melting traces or exposure vectors, define the paths along which the at least one energy beam scans and melts the material and can generally run linearly or non-linearly. This means that additive or generative manufacturing processes differ from conventional abrasive or primary forming manufacturing methods. Examples of additive manufacturing processes are generative laser sintering or laser melting processes, which can be used, for example, to manufacture components for turbomachines such as aircraft engines. In selective laser melting, thin powder layers of the material or the materials used are applied to a building platform and melted and solidified locally with the aid of one or more laser beams in the area of a build-up and joining zone. The construction platform is then lowered, another layer of powder applied and locally strengthened again. This cycle is repeated until the finished component or the finished component area is obtained. The component can then be further processed if necessary or without further

Confirmation copy re processing steps are used. With selective laser sintering, the component is produced in a similar way by laser-assisted sintering of powdery materials. The energy is supplied here, for example, by laser beams from a CC laser, Nd: YAG laser, Yb fiber laser, diode laser or the like. Electron beam processes are also known in which the material is selectively scanned and solidified by one or more electron beams.

A disadvantage of the known layered construction method is the fact that components manufactured with them often have a comparatively high structural anisotropy, which can lead to different mechanical properties depending on the direction. This in turn can lead to reduced strengths and stiffnesses, which have to be taken into account and compensated for in the component design.

The object of the present invention is to improve a layer construction method and a layer construction device of the type mentioned at the outset in such a way that it is possible to manufacture components or component areas with more uniform mechanical properties in different spatial directions. Further objects of the invention consist in specifying a computer program product and a computer-readable storage medium which enable a corresponding control of such a layer construction device. Finally, it is the object of the invention to specify a component with at least one additively manufactured component area with more uniform mechanical properties in different spatial directions.

The objects are achieved according to the invention by a layer construction method with the features of claim 1, by a layer construction device with the features of claim 8, by a computer program product according to claim 10, by a computer-readable storage medium according to claim 11 and by a component according to claim 12. Advantageous refinements with expedient refinements of the invention are specified in the respective subclaims, with advantageous refinements of each aspect of the invention being regarded as advantageous refinements of the other respective aspects of the invention. A first aspect of the invention relates to a layered construction method for the additive manufacture of at least one component region of a component, in particular a component of a flow machine, comprising at least the following steps:

a) providing at least one reference monitoring data set which is based on reference false color values detected by optical tomography of at least one reference component area of a reference component during its additive manufacture and characterizes local intensity maxima of the reference false color values;

b) application of at least one powder layer of a material to at least one building and joining zone of at least one movable building platform;

c) local solidification of the material to form a component layer by the material is selectively scanned and melted with at least one energy beam along scan lines, at least one exposure parameter value of the energy beam depending on the at least one reference monitoring data set and thereby depending on at least one of the local intensity maxima is set;

d) Lowering the construction platform layer by layer by a predefined layer thickness; and e) repeating steps b) to d) until the component area is completed.

This is advantageous because the at least one exposure parameter value can thus be set as a function of the reference false color values, whereby information from the optical tomography of the reference component area and additionally or alternatively the reference component can be used to determine the at least set an exposure parameter value. On the basis of the reference false color values, zones of the reference component area or of the reference component that are produced during the additive manufacturing and heated to different degrees can be detected. Optical tomography makes it possible, for example, to differentiate between warm and cold zones of the differently heated zones. The intensity maxima can characterize the warmest zones. Accordingly, an uppermost intensity maximum of the intensity maxima can characterize the warmest zone. In addition, the invention is based on the knowledge that the warm and cold zones can also be assigned different reference structural structures, that is to say, structural structures of the reference component area and additionally or alternatively of the reference component. A warm zone can arise, for example, through longer exposure to energy beams, which can for example take place through laser irradiation, whereas a In comparison, the cold zone can arise due to a correspondingly shorter application of the energy beam. The duration of the application of the energy beam can, however, have a decisive influence on the reference microstructure, so that larger material grains and greater structural anisotropy can occur with longer exposure to the energy beam (and correspondingly warm zone) than with shorter exposure to the energy beam (cold zone). Correspondingly, information about the respective reference microstructure dependent on the corresponding zones can also flow into the setting of the at least one exposure parameter value of the energy beam via the reference false color values. This makes it possible, for example, to avoid larger temperature differences caused by the energy beam at mutually different points in the component area, which means that, for example, differences in structure anisotropy between the various points can be kept low and the component area can accordingly be created with more uniform mechanical properties in different spatial directions, as, for example, the reference component area. The reference false color values can be designed as reference gray values, for example.

In addition, the reference false color values can be used to identify, for example, respective defects and thus defective structural areas of the reference component area and additionally or alternatively of the reference component. These defects (defective structural areas) can be present in several layers of the reference component area or the reference component and can be detected on the basis of the reference false color values. In the present layer construction method, by setting the at least one exposure parameter value as a function of the reference monitoring data set, it can be avoided that the respective defects occurring in the reference component area or reference component also occur in the component area or the component. This also contributes in an advantageous manner to the design of the component area or the component with more uniform mechanical properties in different spatial directions compared to the reference component area or the reference component.

In an advantageous development of the invention, the at least one reference monitoring data set characterizes a reference structural structure distribution at least in the reference component area and at least one reference exposure parameter value assigned to the reference structural structure distribution. Under the reference microstructure distribution, a distribution of different microstructures in the reference component area and additionally or alternatively be understood in the reference component. By assigning the at least one reference exposure parameter value to the reference structure distribution, a direct relationship between the reference exposure parameter value and the reference structure distribution can be created in an advantageous manner. This allows a particularly targeted setting of the exposure parameter value in order to thereby achieve a particularly desired, in particular homogeneous, structural distribution in the component area.

This is based on the knowledge that the reference structure distribution depends on the reference exposure parameter value. The reference exposure parameter value can correspond, for example, to a reference energy input into the reference component area as a result of the application of an energy beam or an energy beam output, that is to say an energy beam output. For example, it has generally been shown that with a higher reference energy input based on the energy beam in sub-areas of the reference component area, a greater structural anisotropy and thus larger material grains occur in these sub-areas, with the sub-areas of the reference component area with a higher reference energy input also correspondingly higher reference false color values determined by optical tomography, for example in the form of higher gray values, can be recognized, in particular quantified. The higher the reference false color values (for example reference gray values), the greater the corresponding material grains or the corresponding structural anisotropy in the reference component area or in the reference component as a result of the reference energy input.

In a further advantageous development of the invention, depending on the reference structure distribution and the at least one reference exposure parameter value, at least one correction value is determined by which the at least one exposure parameter value is set differently from the at least one reference exposure parameter value, whereby at least the component area with a structure distribution is provided which has a lower defect density and / or a lower number of defects than the reference structure distribution. In other words, the exposure parameter value can differ from the reference exposure parameter value by the correction value. As a result, a particularly targeted reduction in the defect density, in other words a density of defects and additionally or alternatively the number of defects, i.e. with other In other words, a number of the defects occur. Such defects can be formed as faulty structural areas, for example as pores or cracks.

In a further advantageous development of the invention, an energy input of the at least one energy beam is set as the at least one exposure parameter value. This is advantageous because by adjusting the energy input a particularly direct influencing of a microstructure in the component layer and thus in the component area of the component can take place. The energy input can have the unit J / mm ³ and thus indicate an input of energy per unit volume.

In a further advantageous development of the invention, in step c) a monitoring data set based on optical tomography of at least the component layer is created, which is compared with the reference monitoring data set to monitor the additive manufacturing of at least the component area. This is advantageous because pores and, additionally or alternatively, cracks can already be recognized during the additive manufacturing of the component area. The monitoring data set can include false color values recorded by optical tomography during the additive manufacturing of at least the component area. The monitoring can take place in that the false color values are compared with the reference false color values. This makes it possible to recognize if, for example, one of the false color values deviates by an impermissibly large amount from a corresponding reference false color value, which can indicate the presence of pores, cracks or other defects. Like the reference false color values, the false color values can be embodied as gray values, for example. Using the false color values, for example, respective defects and thus defective structural areas of the component area and additionally or alternatively of the component can be recognized at an early stage. These defects (defective structural areas) can be present in several component layers of the component area or the component and can be recognized on the basis of the false color values, in particular by comparing the false color values with the reference false color values. A preferred, layer-by-layer comparison of the false color values with the reference false color values advantageously enables a particularly early and particularly precise assessment of whether, for example, rejects are produced during the manufacture of the component area or the component. In addition, based on the layer-by-layer comparison of the false color values with the reference false color values, a layer-by-layer change in the at least one exposure parameter value can be made take place so that the exposure parameter value is set differently, so to speak, in different component layers of the component area. As a result, it is possible to build further component layers with fewer defects on a component layer that is particularly subject to defects in order to avoid rejects being produced during the production of the component area.

In a further advantageous development of the invention, a laser beam is used as the energy beam in step c). This is advantageous since the laser beam enables particularly targeted local solidification of the material.

In a further advantageous development of the invention, at least one material from the group of steel, aluminum alloys, titanium alloys, cobalt-based alloys, chrome-based alloys, nickel-based alloys, copper alloys, intermetallic alloys or any mixture thereof is used as the material. Although the material can in principle also be a plastic such as ABS, PLA, PETG, nylon, PET, PTFE or the like, components or component areas with higher mechanical, thermal and chemical loading can generally be used with the help of metallic and / or intermetallic materials to be established. For example, the material can contain elements from the iron, titanium, nickel, chromium, cobalt, copper, aluminum or titanium group. The material can be an alloy from the group consisting of steel, aluminum alloy, titanium alloy, cobalt alloy, chromium alloy, nickel-based alloy or copper alloys. For example, the material can be a high temperature-resistant nickel-based alloy such as Mar M-247, Inconel 718 (IN718), Inconel 738 (IN738), Waspaloy or C263. Intermetallic alloys such as Mg2Si and titanium aluminides can also be provided.

A second aspect of the invention relates to a layer construction device for the additive production of at least one component region of a component by an additive layer construction method, comprising:

- At least one powder feed for applying at least one powder layer of a material to at least one build-up and joining zone of at least one movable

Build platform; - At least one radiation source for generating at least one energy beam for layer-by-layer and local solidification of the material by selective scanning and melting of the material along scan lines; and

- a control device which is designed to:

- to control the powder supply so that it applies at least one powder layer of the material to the construction and joining zone of the construction platform; and

- to control the building platform so that it is lowered layer by layer by a predefined layer thickness.

According to the invention it is provided that the control device is set up to control the radiation source and thereby set at least one exposure parameter value of the energy beam as a function of at least one reference monitoring data set, the at least one reference monitoring data set being based on at least one reference component area by optical tomography of a reference component is based on reference false color values detected during its additive production and characterizes local intensity maxima of the reference false color values, the control device being set up to set the at least one exposure parameter value of the energy beam as a function of at least one of the local intensity maxima. The layer construction device can for example comprise a camera, in particular a thermal imaging camera, by means of which the reference false color values of the reference component region of the reference component can be recorded. Further features and their advantages can be found in the descriptions of the first aspect of the invention, with advantageous refinements of the first aspect of the invention being regarded as advantageous refinements of the second aspect of the invention. Conversely, advantageous configurations of the second aspect of the invention are to be regarded as advantageous configurations of the first aspect of the invention.

In an advantageous development of the invention, the layer construction device is designed as a selective laser sintering and / or melting device. In this way, component areas and complete components can be produced whose mechanical properties are at least essentially direction-independent. For example, CO2 lasers, Nd: YAG lasers, Yb fiber lasers, diode lasers or the like can be provided to generate a laser beam as the energy beam. It can also be provided that two or more electron and / or laser beams are used as the respective energy beams. A third aspect of the invention relates to a computer program product, comprising instructions which, when the computer program product is executed by a control device of a layer construction device according to the second aspect of the invention, cause the layer construction device to execute the layer construction method according to the first aspect of the invention. A fourth aspect of the invention relates to a computer-readable storage medium comprising instructions which, when executed by a control device of a layer construction device according to the second aspect of the invention, cause the layer construction device to carry out the layer construction method according to the first aspect of the invention.

The present invention can be implemented with the aid of a computer program product comprising program modules accessible from a computer usable or computer readable medium and storing program code that is used by or in connection with one or more computers, processors or instruction execution systems of a layer building device. For purposes of this description, a computer-usable or computer-readable medium can be any device that can contain, store, communicate, disseminate, or transport the computer program product for use by or in connection with the instruction execution system or layered device. The medium can be an electronic, magnetic, optical, electromagnetic, infrared or semiconductor system or a propagation medium per se, since signal carriers are not included in the definition of the physical, computer-readable medium. These include solid-state or solid-state memory, magnetic tape, a removable computer disk, direct access memory (RAM), read-only memory (ROM), rigid magnetic disk, and an optical disk such as read-only memory (CD-ROM, DVD, Blue-Ray etc.), or a writable optical disc (CD-R, DVD-R). Processors as well as program code for implementing the various aspects of the invention can be centralized or distributed (or a combination thereof).

A fifth aspect of the invention relates to a component, in particular a turbine component of a turbomachine, comprising at least one component area which is produced by means of a layer construction device according to the second aspect of the invention and / or by means of a layer construction method according to the first aspect of the invention. As a result, the component according to the invention has a highly uniform and at least essentially direction-independent joint structure, which leads to a significantly higher resistance to cyclic loads as well leads to significantly increased strength and stiffness values. The features resulting therefrom and their advantages can be found in the descriptions of the first and second aspects of the invention, with advantageous configurations of each aspect of the invention being regarded as advantageous configurations of the other aspects of the invention. The component can be designed as a turbine blade for a gas turbine, in particular for an aircraft engine.

Further features of the invention emerge from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respectively specified combination, but also in other combinations, without the scope of the Invention to leave. There are thus also embodiments of the invention to be considered as encompassed and disclosed, which are not explicitly shown and explained in the figures, but emerge from the explained embodiments and can be generated by separate combinations of features. Designs and combinations of features are also to be regarded as disclosed, which therefore do not have all the features of an originally formulated independent claim. In addition, designs and combinations of features, in particular through the statements set out above, are to be regarded as disclosed which go beyond the combinations of features set forth in the back references of the claims or differ from them. It shows:

1 shows a schematic sectional view of a layer construction device;

2 shows a schematic representation of a layer surface of a reference component region of a reference component during its additive production, with reference false color values of the layer surface determined by optical tomography being shown;

3 shows a schematic representation of a layer surface of a component region of a component during its additive production, with false color values of the layer surface determined by optical tomography being shown; FIG. 4 shows a schematic detailed view of a surface segment within an area A framed by in FIG. 2; FIG.

5 shows a schematic detailed view of a further surface segment within a region B framed in FIG. 2;

6 shows a micrograph showing a reference microstructure of the reference component area; and

Fig. 7 shows a further micrograph showing a further reference microstructure of the reference component area.

FIG. 1 shows a schematic sectional view of a layer construction device 10. The layer construction device 10 is used for the additive manufacture of at least one component region 12 of a component 14 by an additive layer construction method. The layer construction device 10 comprises at least one powder feed 16 with a powder container 18 and a coater 20. The powder feed 16 is used to apply at least one powder layer of a material 22 to a construction and joining zone II of a construction platform 24 that can be moved according to arrow B. For this purpose, the coater 20 moved according to arrow III in order to transport material 22 from the powder container 18 to the building and joining zone II. The layer construction device 10 further comprises at least one radiation source 26 for generating at least one energy beam 28, for example in the form of a laser beam, for layer-wise and local solidification of the material 22 by the material 22 with the energy beam 28 along in Fig. 2 and 3 schematically indicated scan lines 40 is selectively scanned and melted. In addition, a control device 30 is provided, which is designed to control the powder feed 16 so that it applies at least one powder layer of the material 22 to the building and joining zone II of the building platform 24 and the building platform 24 in layers by a predefined layer thickness according to the arrow B lowers. Furthermore, the layer construction device 10 comprises an optical specific device 32, by means of which the energy beam 28 can be moved over the build-up and joining zone II. The radiation source 26 and the device 32 are coupled to the control device 30 for data exchange. Furthermore, the layer construction device 10 comprises a heating device 34, by means of which the powder bed can be heated to a desired base temperature. The heating device 34 can, for example, have one or more induction coil (s) include. Alternatively or additionally, other heating elements, for example IR radiators or the like, can also be provided.

The control device 30 is set up to control the radiation source 26 and thereby set at least one exposure parameter value of the energy beam 28 as a function of at least one reference monitoring data set 50. The reference monitoring data set 50 is based on reference false color values 64 recorded by optical tomography of at least one reference component region 60 of a reference component 62 during its additive production, as can be seen in FIG. In addition, the reference monitoring data set 50 characterizes local intensity maxima 66 of the reference false color values 64. The control device 30 is also set up to set the at least one exposure parameter value of the energy beam 28 as a function of at least one of the local intensity maxima 66. The reference monitoring data record 50 can be stored in a memory of the control device 30 and thus made available for the additive production of the component area 12 of the component 14 by the additive layer construction method. The reference component region 60 and the component region 12 can preferably be congruent to one another. Accordingly, the reference component 62 and the component 14 can also be congruent to one another. The layer construction device 10 in the present case comprises a camera 36, in particular a thermal imaging camera, by means of which the reference false color values 64 can be recorded. The camera 36 is coupled to the control device 30 for data exchange.

FIG. 2 shows a schematic representation of a layer surface of the reference component region 60 and thus at least a section of the reference component 62 during its additive production using the layer construction device 10. In addition, the reference false color values determined using the camera 36 by optical thermography are shown in FIG 64 and the various local intensity maxima 66 of the reference false color values 64 can be seen.

The reference monitoring data set 50 characterizes a reference structure distribution in the entire reference component 62 and in the reference component area 60. In addition, the reference monitoring data set 50 characterizes at least one reference exposure parameter value assigned to the reference structure distribution. The reference exposure parameter value can for example correspond to an energy input, which can be caused by the energy beam 28 to produce the reference component 62 from the material 22 during the additive production of the reference component 62. The energy input can also be referred to as energy input. Furthermore, the energy can be introduced as a function of location and additionally or alternatively as a function of the geometry.

The control device 30 is also set up to determine at least one correction value as a function of the reference structure distribution and the at least one reference exposure parameter value. The at least one exposure parameter value is then set to differ by the at least one correction value from the at least one reference exposure parameter value, whereby at least the component region 12 is provided with a structure distribution which has a lower defect density and / or a lower number of defects than the reference structure distribution.

FIG. 3 shows, in a schematic representation, the layer surface of the component region 12 and thus at least a section of the component 14 during its additive manufacture by the layer construction method. In Fig. 3 also respective false color values 74 determined by means of the camera 36 by optical thermography can be seen. Just like the reference false color values 64, the false color values 74 are also recorded and stored in layers with the aid of the camera 36. Thus, based on the false color values 74 and thus on optical tomography of the various component layers, the monitoring data record 70 is created, which is compared with the reference monitoring data record 50 for monitoring the additive manufacturing of at least the component region 12. The monitoring data record 70 is stored in the memory of the control device 30.

From the synopsis of FIGS. 2 and 3 it can be seen that during the production of the construction sub-area 12 (see FIG. 3), a significantly more uniform introduction of energy by means of the energy beam 28 takes place than during the production of the reference component area 60 (see FIG Fig. 2).

FIG. 4 and 5 each show schematic detailed views of different surface segments of the reference component area 60. FIG. 4 shows an enlarged illustration of an area A outlined in FIG. 2, whereas FIG. 5 shows an enlarged illustration of an area B outlined in FIG . In area A, during additive manufacturing, a greater amount of energy was introduced using the energy beam 28, with one of the intensity maxima 66 increasing in area A recognize is. Accordingly, a greater number of defects 76 (number of defects) in the form of pores and cracks and a greater density of defects 76 (defect density) can be seen in area A than in area B, as can be seen from a synopsis of FIGS. 4 and 5 .

FIG. For further clarification, FIG. 6 shows a micrograph of the region B shown in FIG. 5, whereas FIG. 7 shows a further micrograph of the region A shown in FIG. The representations shown in FIG. 6 and FIG. 7 can be obtained, for example, by electron backscattering (EBSD). From the synopsis of FIGS. 6 and 7 it can be seen that a low energy input can lead to lower reference false color values 64 as well as to a lower grain size (see FIG. 6) in a microstructure of the reference component region 60, whereas a comparison in addition, greater energy input can lead to greater false reference color values 64 and to greater grain size (see FIG. 7) in the microstructure of the reference component region 60. Overall, it has been shown that with a higher energy input based on the energy beam 28 in partial areas of the reference component area 60 or the component area 12, a greater structural anisotropy and thus larger material grains also occur in these partial areas, with the partial areas with higher energy input also through Correspondingly higher reference false color values 64 or false color values 74 determined by optical tomography, for example in the form of higher gray values, can be recognized, in particular quantified. The higher the reference false color values 64 or false color values 74 are, the greater are the corresponding material grains and the corresponding structural anisotropy as a result of the energy input.

The present layer construction method or the present layer construction device 10 enables an effective estimation of an expected defect distribution in the form of a defect frequency and defect size or the defect density and additionally or alternatively the number of defects depending on the component geometry using the determined reference false color values 64 or false color values 74 , which can be, for example, respective gray values. Optical tomography can use the reference false color values 64 or

False color values 74 a respective evaluation of an orientation and distribution of material grains of medium and maximum size take place. Using the optical tomography, a heat balance in the component 14 or in the component area 12 influenced by the melting using the energy beam 28 can also be optimized. Optical tomography makes it possible to identify respective partial areas on the basis of the reference false color values 64 or false color values 74, in which different temperatures prevail. The optical tomography can, for example, take into account heat conduction conditions in the component area 12 or in the reference component area 60 due to the respective component geometry and thus avoid unwanted changes in influencing variables such as a scan vector length and a track overlap. As a result, undesired, essential changes in the respective reference microstructure or microstructure and associated changes in the material properties (static and cyclic strength, defect density) of the melted material 22 can be avoided.

The layer construction method or the layer construction device 10 make it possible to use the local intensity maxima 66 in order to set the heat balance in a targeted manner. In addition, a reference false color mean value can also be formed from the reference false color values 64 in order to keep the additive manufacturing of the component region 12 or the component 14 based on the reference false color mean value, which can be designed as a gray value position mean value, layer by layer.

Using the present layer construction method or using the layer construction device 10, a correlation between the local intensity maxima 66 of the reference false color values 64 and the material properties of the material 22 and the defect distribution can be used to additively produce the component region 12 or the component 14.

By analyzing the respective layer data of the reference component region 60 or the reference component 62 recorded with the aid of the camera 36 in relation to the local intensity maxima 66, the changes in the heat balance, as can be seen from FIG. 2, can be shown and evaluated.

The reference component area 60 or the reference component 62 can initially be built up with a constant reference exposure parameter value of the energy beam 28 and recorded by optical tomography, whereby the reference false color values 64 can be recorded in layers, for example as reference gray values. A normalization and adjustment of the recorded reference false color values 64 to a defined reference target value (with defined reference microstructure and defect distribution) can be an input variable for calculating a parameter related to the component geometry of the component region 12 or the component 14 be in the form of the at least one exposure parameter value which, as the target, provides a more uniform microstructure and defect distribution in the component region 12 or in the component 14.

For example, if the reference false color values 64 show intensity fluctuations of 20% during the additive manufacture of the reference component area 60 or the reference component 62, the at least one exposure parameter value for the additive manufacture of the component area 12 or the component 14 can be set in this way that the energy input during the production of the component region 12 or the component 14 is reduced by 20% compared to the additive production of the reference component region 60 or the reference component 62.

The analysis of the local reference false color values 64 (for example the local reference gray values) enables a local and thus location-dependent evaluation of the heat balance and the resulting material properties in the reference component 62 or the component 14. The analysis of the local reference false color values 64 can be carried out as Input variable can be used for the structural geometry-dependent adaptation of the exposure parameter value. By means of a three-dimensional analysis of a reference image stack composed of respective individual layers of the reference component region 60 or the reference component 62, particularly relevant regions for a destructive test can be identified. The possibility of monitoring the reference false color values 64 can also be used to secure parameters for specific structural settings with specific mechanical properties.

List of reference symbols:

10 layer construction device

12 Component area

14 component

16 powder feed

18 powder containers

20 coaters

22 material

24 building platform

26 Radiation source

28 energy beam

30 control device

32 Setup

34 Heater

36 camera

40 scan line

50 Reference monitoring data record 60 Reference component area

62 Reference component

64 reference false color values

66 local maximum intensity

70 Monitoring data set

74 false color values

76 defect

11 Build-up and joining zone

III arrow

B Movement of the build platform

Claims

1. Layered construction method for the additive manufacture of at least one component region (12) of a component (14), in particular a component (14) of a turbo machine, comprising at least the following steps:

a) Providing at least one reference monitoring data set (50) which is based on reference false color values (64) recorded by optical tomography of at least one reference component area (60) of a reference component (62) during its additive production and local intensity maxima (66) the reference false color values (64) characterized;

b) applying at least one powder layer of a material (22) to at least one build-up and joining zone (II) of at least one movable building platform (24); c) local solidification of the material (22) to form a component layer by the material (22) being selectively scanned and melted with at least one energy beam (28) along scan lines (40), at least one exposure parameter value of the energy beam (28) in Is set as a function of the at least one reference monitoring data set (50) and thereby as a function of at least one of the local intensity maxima (66);

d) lowering the construction platform (24) layer by layer by a predefined layer thickness; and

e) repeating steps b) to d) until the component area (12) is completed.

2. Layer construction method according to claim 1,

characterized in that

the at least one reference monitoring data set (50) characterizes a reference structure distribution at least in the reference component area (60) and at least one reference exposure parameter value assigned to the reference structure distribution.

3. Layer construction method according to claim 2,

characterized in that As a function of the reference structure distribution and the at least one reference exposure parameter value, at least one correction value is determined by which the at least one exposure parameter value is set differently from the at least one reference exposure parameter value, whereby at least the component area (12) is provided with a structure distribution, which has a lower defect density and / or a lower number of defects than the reference structure distribution.

4. Layer construction method according to one of the preceding claims,

characterized in that

an energy input of the at least one energy beam (28) is set as the at least one exposure parameter value.

5. Layer construction method according to one of the preceding claims,

characterized in that

in step c) a monitoring data set (70) based on optical tomography of at least the component layer is created, which is compared with the reference monitoring data set (50) to monitor the additive manufacturing of at least the component area (12).

6. Layer construction method according to one of the preceding claims,

characterized in that

in step c) a laser beam is used as the energy beam (28).

7. Layer construction method according to one of the preceding claims,

characterized in that

as the material (22) at least one material from the group steel, aluminum alloys, titanium alloys, cobalt-based alloys, chromium-based alloys, nickel-based alloys, copper alloys, intermetallic alloys or any mixture thereof is used.

8. Layer construction device (10) for the additive production of at least one component region (12) of a component (14) by an additive layer construction method, comprising: - At least one powder feed (16) for applying at least one powder layer of a material (22) to at least one construction and joining zone (II) of at least one movable construction platform (24);

- At least one radiation source (26) for generating at least one energy beam (28) for layer-by-layer and local solidification of the material (22) by selective scanning and melting of the material (22) along scan lines (40); and

- A control device (30) which is designed to:

- to control the powder feed (16) so that it applies at least one powder layer of the material (22) to the build-up and joining zone (II) of the build platform (24); and

- to control the construction platform (24) so that it is lowered in layers by a predefined layer thickness,

characterized in that

the control device (30) is set up to control the radiation source (26) and thereby set at least one exposure parameter value of the energy beam (28) as a function of at least one reference monitoring data set (50), the at least one reference monitoring data set (50) being through optical tomography of at least one reference component area (60) of a reference component (62) is based on reference false color values (64) recorded during its additive creation and characterizes local intensity maxima (66) of the reference false color values (64), the control device (30) is set up to set the at least one exposure parameter value of the energy beam (28) as a function of at least one of the local intensity maxima (66).

9. layer construction device (10) according to claim 8,

characterized in that

this is designed as a selective laser sintering and / or melting device.

10. Computer program product, comprising instructions which, when the computer program product is executed by a control device (30) of a layer construction device (10) according to claim 8 or 9, cause the layer construction device (10) to carry out the layer construction method according to one of claims 1 to 7.

11. Computer-readable storage medium, comprising instructions which, when executed by a control device (30) of a layer construction device (10) according to claim 8 or 9, define the layer cause construction device (10) to carry out the layer construction method according to one of claims 1 to 7.

12. Component (14), in particular turbine component of a turbomachine, comprising at least one component area (12) which is produced by means of a layer construction device (10) according to claim 8 or 9 and / or by means of a layer construction method according to one of claims 1 to 7.