Method for manufacturing a plurality of components within the scope of an additive manufacturing process

Abstract

The proposed solution relates to a method for manufacturing a plurality of components (1a-1d, 2a, 2g) by means of a powder having particles (P1-P5) in the context of an additive manufacturing process, the powder being at least partially melted in order to shape the plurality of components (1a-1d, 2a, 2g). Here, the plurality of components (1a-1d, 2a, 2g) can be shaped in a component layer (L8) extending along a manufacturing plane, in which component layer a first component (1a) is adjacent to a second component (1b) of the component layer (L8) at least in the spatial direction (x, y) along the manufacturing plane. It is proposed in this connection that a gap (g) having a gap width (s) is provided between the first component (1a) and the second component (1b) of the component layer (L8), which gap width is predetermined in the case of a particle size distribution of the particles (P1-P5) in the powder.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing multiple components using powder having granules within the scope of an additive manufacturing process. Background Technology

[0002] For example, it is known to manufacture multiple components by additive laser melting. Here, these components are constructed layer by layer in a powder bed. The powder is at least partially melted to form multiple components so as to manufacture multiple components in at least one component layer extending along the manufacturing plane, in which a first component in a spatial direction exists adjacent to at least one second component.

[0003] To hold the component to be manufactured in the powder bed, especially to prevent possible warping and to dissipate excess heat, a support structure is formed, for example, from the same material as the component itself (i.e., especially metal). Because the support structure is only needed during the manufacturing process, it is usually removed after additive manufacturing, typically manually. Therefore, the entire process is relatively costly and expensive. Summary of the Invention

[0004] In this context, the objective of the present invention is to further improve the manufacturing method.

[0005] This task is solved using a method according to the invention for manufacturing multiple components using powder having granules within the scope of an additive manufacturing process.

[0006] According to a first aspect of the invention, a gap having a gap width is provided between a first member and a second member of the member layer, the gap width being preset when using the particle size distribution of particles in the powder.

[0007] In this regard, the basic concept of the proposed solution is to provide support for the first and second components adjacent to each other on the particles located in the gaps. Since the gap width is determined according to the particle size distribution, the distance between the components can be adjusted in relation to the particles without setting up separate support structures, and more specifically, in such a way that no movement of the particles located in the gaps occurs during the manufacturing process, and therefore no movement of the components relative to each other, even in the event of force transmission between the components due to factors such as warping. Therefore, the function of a separately constructed support structure can be assumed by the particles located in the gaps of the powder used for forming. Thus, a support structure as an independent geometry is not necessary during the manufacturing process, and the support structure does not need to be additively manufactured during the manufacturing process.

[0008] In one implementation variation, the gap width is preset based on the particle size distribution, and the gap width determines the average distance between the first component and the second component that is (directly) adjacent in the manufacturing plane during the forming of the first and second components. Therefore, in the powder bed used for manufacturing, the first and second components are separated from each other only by the gap when the manufacturing process is completed.

[0009] For example, the adjusted gap width corresponds to the average particle size of the particles in the powder. Therefore, the average particle size for the gap width can, for example, correspond to a value in the particle size distribution within the range of d90 and d100 (especially +10%). In particular, the average particle size for the gap width can correspond to the d90 or d95 value of the particle size distribution. The gap width corresponding to the average particle size of d90 or d95 of the particle size distribution is understood, for example, as corresponding to the diameter of the particles in the powder such that 90% (d90) or 95% (d95) of the particles present in the powder do not exceed this diameter. In other words, 90% or 95% of the particles in the powder have a diameter equal to or less than the d90 / d95 value.

[0010] Within a component layer, a first component may exist adjacent to a second component in two mutually perpendicular spatial directions along the manufacturing plane, with the second components spaced apart from the first component by a gap width. The first component can thus be surrounded within the powder among a plurality of (at least two) second components, wherein support is provided at the gaps, the gap width of which is predetermined based on the particle size distribution within the powder. Therefore, for example, the first component may be centrally arranged between four second components in the component layer along two mutually perpendicular spatial axes.

[0011] In principle, the first and second components can be part of a first component layer of the component block, wherein at least one second component layer of the component block for additional components that can be formed from powder extends parallel to the first component layer. The component block thus comprises at least two component layers in which multiple components exist side-by-side at the end of the manufacturing process. Therefore, at the end of the additive manufacturing process, multiple layers exist within the component block, each having multiple rows of components.

[0012] In principle, the first and second components, as well as components in different component layers, can be constructed identically, thereby additively manufacturing a component block with a large number of identical components from powder via an additive manufacturing process.

[0013] According to another aspect of the proposed solution (which may be used alternatively or supplementally in the proposed method relative to the first aspect), in order to lock at least two components of different component layers together during the manufacturing process, a sintered bridge layer is formed between the first and second component layers.

[0014] During additive manufacturing, the sintered bridge layer establishes a material-locked connection between components of different component layers. This material-locked connection is designed such that it is specifically designed to fail under force applied manually or via a removal robot when removing a component from a component block comprising at least the first and second component layers, thereby allowing components of different component layers to separate from each other along the sintered bridge layer. For example, the sintered bridge layer is constructed to be thin and brittle during the additive manufacturing process, so that it fails under force exceeding a preset threshold. Therefore, the sintered bridge layer is only configured for temporary fixation during the additive manufacturing process and is constructed to be relatively thin for this purpose. To construct the sintered bridge layer during the additive manufacturing process, the powder used for manufacturing is melted accordingly via pre-adjusted process parameters, for example, exposed accordingly.

[0015] For example, the sintered bridge layer has a thickness that corresponds only to a fraction of the predetermined layer thickness of the component layer through the height of the component in that component layer. For example, if components of predetermined heights are stacked layer by layer in a component layer, then the layer thickness corresponds to the maximum height of its components. For example, the thickness of the sintered bridge layer connecting the components of two component layers is a maximum of 1 / 10, 1 / 20, or 1 / 40 of the layer thickness of a component layer. However, in a variant implementation, the sintered bridge layer can also be determined in association with the average thickness of the melt traces made of molten powder, by which components are constructed layer by layer. For example, the thickness of the sintered bridge layer is in the range of 1 to 15 melt trace thicknesses, particularly in the range of 5 to 10 melt trace thicknesses. Therefore, if the component is constructed layer by layer by melt traces with an average melt trace thickness x, then the thickness of the sintered bridge layer is, for example, in the range from x to 15x, particularly in the range from 5x to 10x.

[0016] In one embodiment of the proposed solution, multiple components are formed by additive laser melting. In this variation, the forming of the components is thus achieved in a powder bed by at least local melting of the powder bed using at least one laser.

[0017] In a variant combining the two aspects described above, the first and second components are locked within their component layers (relative to their respective manufacturing planes) by means of a pre-defined gap width according to the particle size distribution. Furthermore, a sintered bridge layer provides additional locking on at least one of the first and second components relative to at least one component of another component layer, and thus perpendicular to the manufacturing planes of the first and second component layers. Therefore, for example, a pre-defined gap width related to the particles ensures support for the component to be manufactured in the xy manufacturing plane during the additive manufacturing process, and thus ensures locking, while the sintered bridge layer manufactured during the additive manufacturing process provides locking perpendicular to it, i.e., along the z-axis. Thus, the fixation of the (first) component in the x and y directions can be achieved by adjacent (second) components, where force transmission is achieved via particles in a thick powder layer within the separated gaps. Loose sintering is provided via the sintered bridge layer to fix the components on multiple overlapping component layers. Similar to force transmission, heat can be discharged via the powder layer in the gaps or the defined component voids between the components of the component layers, and via the sintered bridge layer between the component layers. Attached Figure Description

[0018] The accompanying drawings exemplify possible variations of the invention. Wherein: Figure 1 The component layer of the component block is shown in a fragment and in sectional view, the component block having multiple components that are additively formed side by side and superimposed according to an implementation variation of the proposed manufacturing method; Figure 2A The diagram shows the relationship between two overlapping components. Figure 1 The extracted detailed image shows that the two components are connected to each other in a locking manner via loose sintering provided by sintered bridge layers; Figure 2B It shows Figure 2A Enlarged fragments of detailed images; Figure 3 The image shows, at a magnified scale, two side-by-side components in a component layer, with a gap between them having a gap width of exactly one particle for the powder used in manufacturing. Figures 4A-4B With Figure 3 The coordinated view shows two side-by-side components separated by a gap, where the gap is not pre-set too small according to the proposed solution. Figure 4A ) or too large ( Figure 4B ); Figure 5 The perspective view shows a component block manufactured according to a variant of the proposed solution, which has multiple stacked component layers, each layer comprising multiple rows of identical components arranged side by side. Detailed Implementation

[0019] Figure 5 A perspective view shows a cuboid component block BB, which is generated in a powder bed via additive manufacturing (here, additive laser melting). Component block BB comprises multiple, in this case, eight component layers L1 to L8, stacked along the spatial direction z on a support platform T. Each component layer L1 to L8 extends along a manufacturing plane, which is currently extended along spatial directions x and y, respectively, perpendicular to the z direction. Within each component layer L1 to L8, multiple identical components are arranged side-by-side along both spatial directions x and y.

[0020] In the uppermost component layer L8, an exemplary (first) component 1a on the edge side is shown, with second components 1b to 1d adjacent to it within the same component layer L8. Components of the same construction are formed in the lower component layer L7, with component 2a positioned directly below the first component 1a, which sits atop the first component 1a at the end of the additive manufacturing process. Component 2a in the lower component layer L7 is also adjacent to another identical component, such as the second component 2g.

[0021] exist Figure 5 In the case of the component block BB shown, each component 1a to 1d, 2a, and 2g is formed in powder without a supporting structure. For this purpose, on the one hand, component gaps in the form of gaps g are provided between the components of component layers L1 to L8, and therefore between components that are directly adjacent to each other in the spatial directions x and y in the xy manufacturing plane. Two adjacent components are constructed to be spaced apart from each other by gap g with a gap width s, the gap width being preset based on the particle size distribution P1 to P5 present in the powder bed. On the other hand, adjacent components of different component layers L1 to L8 are connected to each other for the additive manufacturing process by means of loose sintering provided by sintering bridge layer 12. Here, the gap width s, selected in relation to the particles between the components of component layers L1 to L8, ensures support and thus locking of the components to be formed in the x and y directions, while locking in the z direction during the additive manufacturing process is ensured via the sintering bridge layer 12 between component layers L1 to L8.

[0022] according to Figure 1The image shows, at a magnified scale, the gap g between two adjacent components 1a and 1b in component layer L8. Here, component 1a is shown connected to component 2a of the underlying component layer L7 via a sintered bridge layer 12. The gap width s of the gap g between the first component 1a and its adjacent component 1b in the same component layer L8 is predetermined based on the particle size distribution of particles P1 to P5 present in the powder bed. Here, the predetermined gap width s corresponds, for example, to the average particle size d95 of the particle size distribution, such that the gap width s of the gap g between components 1a and 1b corresponds to the average diameter d, of which 95% of the particles P1 to P5 present in the powder bed do not exceed this average diameter. Therefore, it is possible to have a powder layer of exactly one particle width in the gap g, and thus the force transmission between components 1a and 1b occurs through exactly one particle P1 within the gap g. Thus, force can be transmitted directly via a single particle P1 to P5, without the (powder) particles P1 to P5 moving relative to each other.

[0023] For locking along the z-direction, a sintered bridge layer 12 is formed on the base layer 10 of component 1a (which serves as the base surface of component 1a facing the lower component 2a of the underlying component layer) during the additive manufacturing process. The loose protection provided by this sintered bridge layer 12 is constructed here by correspondingly adjusted process parameters, and a temporary shape-locking connection is formed between components 1a and 2a in the successive component layers (here, component layers L7 and L8). Figure 2A In additive laser melting, the sintered bridge layer 12, constructed through corresponding exposure, is here (as in...). Figure 1 As shown in the diagram, it is used not only for locking in the z-direction during the additive manufacturing process, but also for defined heat transfer W2 between components 1a and 2a when heat input W is applied to one of the components 1a and 2a. Furthermore, when heat input W is applied, heat transfer W1 within the same component layer is also ensured via particles P1 to P5 in the gap g.

[0024] from Figure 2B As can be seen in the enlarged view, the thickness c of the sintered bridge layer 12 corresponds only to a small fraction of its height in the z-direction and therefore only to a small fraction of the layer thicknesses of the component layers L1 to L8. Currently, the thickness c of the sintered bridge layer 12 is in the range of two to ten times the average thickness corresponding to the melt trace, which is used to additively construct the components of the component layers L1 to L8 layer by layer. The thickness c of the sintered bridge layer 12 here depends on the energy input to the corresponding lowermost melt trace of the component located above the generated sintered bridge layer 12 (e.g., in the...). Figure 2BThe energy input to the lowest melting trace of component 1a depends on the energy. If components 1a and 2a are made of aluminum powder, for example, then there will be a gap of about 5 to 10 melting traces (thickness) between the two components 1a and 2a in the region of the sintered bridge layer 12 to be formed.

[0025] Figure 3 The enlarged view further illustrates the transmission of force F between adjacent components 1a and 1b in a component layer via individual particles P1 to P5 in the pre-defined component gaps via gap g. Force F is transmitted via individual particle P1 to the facing sides 11a and 11b of the two components 1a and 1b. Components 1a and 1b can thus be supported by each other via a component gap of one particle width without a supporting structure, or more precisely, without the components 1a and 1b in the same component layer being connected to each other.

[0026] If the gap width s of the gap g is chosen to be too small relative to this (e.g.) Figure 4A As shown, this creates a risk that components 1a and 1b are directly and shape-locked together, which could lead not only to undesirable tension but also to deformation. If the gap width s is too large, such as... Figure 4B As shown, the introduced force F is transmitted as a component force F1 or F2 from one particle in the powder layer to an adjacent particle. This causes displacement of the particle and consequently movement of the adjacent component. Therefore, locking of the component in the xy manufacturing plane cannot be guaranteed.

[0027] By strategically presetting the gap width s for adjacent components 1a and 1b, and by utilizing the component voids generated during additive manufacturing when using a particle size distribution, it becomes possible to lock components within the component block BB to be manufactured without using a support structure. This reduces process costs due to the reduced exposure time. Material consumption is also reduced if a separate support structure does not need to be formed together. Post-processing costs for additively manufactured components are also reduced because the support structure does not need to be removed afterward. Furthermore, the full utilization of the (manufacturing) space provided by the support platform T used for manufacturing is improved.

[0028] Components manufactured using exemplary variations of the proposed manufacturing method can be, for example, vehicle parts, particularly parts for vehicle seats, such as seat height limiters, seat corner pieces, or protrusions for seat adjustment mechanisms.

[0029] List of reference numerals

[0030] Components 1a-1d, 2a, 2g

[0031] 10. Basal layer

[0032] Side views of 11a and 11b

[0033] 12 Sintered bridge layers

[0034] BB component blocks

[0035] c layer thickness

[0036] d Diameter

[0037] Forces F, F1, and F2

[0038] g, g1, g2 gaps

[0039] L1-L8 Component Layer

[0040] P1-P5 particles

[0041] s gap width

[0042] T-type carrier platform

[0043] W Hot Input

[0044] W1, W2 heat transfer

Claims

1. A method for manufacturing multiple components (1a-1d, 2a, 2g) using powder having particles (P1-P5) within the scope of an additive manufacturing process, wherein the powder is at least partially melted to form the multiple components (1a-1d, 2a, 2g), wherein, The plurality of components (1a-1d, 2a, 2g) are formed in a component layer (L8) extending along a manufacturing plane, wherein a first component (1a) is adjacent to a second component (1b) of the component layer (L8) at least in the spatial directions (x, y) along the manufacturing plane. Its features are, A gap (g) with a gap width (s) formed by powder particles (P1-P5) is provided between the second component (1b) and the first component (1a) of the component layer (L8). The gap width is preset based on the particle size distribution of the particles (P1-P5) in the powder, thereby providing support for the first and second components (1a, 1b) adjacent to each other on the particles (P1-P5) located in the gap (g), and the particles (P1-P5) located in the gap (g) perform the function of preventing the first and second components (1a, 1b) from moving during the manufacturing process. The gap width (s) determines the average distance between the first component (1a) and the second component (1b) adjacent in the manufacturing plane during the manufacturing of the first and second components (1a, 1b), and the gap width (s) is preset based on the particle size distribution and corresponds to the average particle size of the particles (P1-P5) in the powder.

2. The method according to claim 1, characterized in that, The average particle size for the gap width (s) corresponds to a particle size distribution that is within 110% of the d90 and d100 values.

3. The method according to claim 1, characterized in that, The first component (1a) is adjacent to the second component (1b, 1d) in two mutually perpendicular spatial directions (x, y) along the manufacturing plane, and the second component is spaced apart from the first component (1a) by the gap width (s).

4. The method according to claim 1, characterized in that, The first and second components (1a, 1b) are part of the first component layer (L8) of the component block (BB), and at least one second component layer (L7-L1) of the component block (BB) for additional components (2a, 2g) that can be formed from powder extends parallel to the first component layer.

5. The method according to claim 1, characterized in that, The forming of the multiple components (1a-2d, 2a, 2g) is achieved by additive laser melting.

6. The method according to claim 5, characterized in that, The first and second components (1a, 1b) are locked within their component layer (L8) by means of a gap width (s) preset according to the particle size distribution, and additional locking of the first and second components (1a, 1b) relative to the components of the other component layer (L7-L1) is achieved at the first and second components (1a, 1b) via a sintered bridge layer (12), and further additional locking is achieved perpendicular to the manufacturing plane of the first and second components (1a, 1b).

7. The method according to claim 1, characterized in that, The average particle size for the gap width (s) is the d90 or d95 value of the particle size distribution.

8. A method for manufacturing multiple components (1a-1d, 2a, 2g) using powder having particles (P1-P5) within the scope of an additive manufacturing process, wherein the powder is at least partially melted to form the multiple components (1a-1d, 2a, 2g), wherein, The plurality of components (1a-1d, 2a, 2g) are formed in a stacked arrangement in at least two mutually parallel extending component layers (L1-L8), such that several components (1a) of the first component layer (L8) are formed above several components (2a) of the second component layer (L7). Its features are, In the first and second component layers, gaps formed by powder particles with a gap width are provided between adjacent components. The gap width is preset based on the particle size distribution in the powder, thereby providing support for adjacent components on the particles located in the gaps and the particles located in the gaps serve to prevent component movement during the manufacturing process. The gap width determines the average distance between adjacent components within the same component layer during manufacturing, and the gap width is preset based on the particle size distribution and corresponds to the average particle size in the powder. In order to lock the components (1a, 2a) of the first and second component layers (L8, L7) together during the additive manufacturing process, a plurality of sintered bridge layers (12) are formed between the components (1a, 2a) of the first and second component layers (L8, L7).

9. The method according to claim 8, characterized in that, The sintered bridge layer (12) has a thickness that corresponds only to a small portion of the preset layer thickness of the component layers (L8, L7) through the height of the components (1a-1d, 2a, 2g) of their respective component layers (L8, L7).

10. The method according to claim 8, characterized in that, The forming of the multiple components (1a-2d, 2a, 2g) is achieved by additive laser melting.

11. The method according to claim 9, characterized in that, The first and second components (1a, 1b) are locked within their component layer (L8) by means of a gap width (s) preset according to the particle size distribution, and additional locking of the first and second components (1a, 1b) relative to the components of the other component layer (L7-L1) is achieved at the first and second components (1a, 1b) via the sintered bridge layer (12), and further additional locking is achieved perpendicular to the manufacturing plane of the first and second components (1a, 1b).

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