AM device

Abstract

To provide a technique for uniformly supplying powder to the DED nozzle.SOLUTION: According to an embodiment, an AM device for producing a modeling object is provided, the AM device has a DED nozzle, the DED nozzle has a powder outlet at a tip of the DED nozzle body for ejecting a powder material, and a powder passage for powder material to pass through the DED nozzle body in connection with the powder outlet, the AM device further has first piping, a separation wall extending from an end of the first piping to an inner upstream end of the first piping, and a plurality of second piping connected to the end of the first piping, the separation wall divides the end of the first piping into a plurality of partitions, each of the plurality of second piping is connected to each of the plurality of partitions of the first piping, and the second piping is connected to the powder passageway of the DED nozzle.SELECTED DRAWING: Figure 6A

Description

Technical Field

[0001] This application relates to an AM device.

Background Art

[0002] There is a known technique for directly fabricating a three-dimensional object from three-dimensional data on a computer representing the three-dimensional object. For example, the Additive Manufacturing (AM) (additive manufacturing) method is known. As an example, there is Direct Energy Deposition (DED) as a deposition-type AM method. DED is a technique for performing fabrication by melting and solidifying together with a base material using an appropriate heat source while locally supplying a metal material. Further, as an example of the AM method, there is Powder Bed Fusion (PBF). PBF irradiates a two-dimensionally spread metal powder with a laser beam or an electron beam, which is a heat source, to the portion to be fabricated, and melts, solidifies or sinters the metal powder to fabricate each layer of the three-dimensional object. In PBF, by repeating such steps, a desired three-dimensional object can be fabricated.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a DED system, a laser or electron beam, which serves as a heat source, is generally supplied from a DED nozzle to a predetermined location. The DED nozzle also supplies the material powder along with a carrier gas to the predetermined location. The DED nozzle has powder passages through which the material powder passes and powder outlets for ejecting the powder. To uniformly supply the material powder to the predetermined location, multiple powder passages and powder outlets may be formed in the DED nozzle. In this case, it is desirable to supply uniform powder to each powder passage. One objective of this application is to provide a technology for uniformly supplying material powder to a DED nozzle. [Means for solving the problem]

[0005] According to one embodiment, an AM apparatus for manufacturing a molded object is provided, the AM apparatus having a DED nozzle, the DED nozzle having a powder port provided at the tip of the DED nozzle body for ejecting powder material, and a powder passage communicating with the powder port for the powder material to pass through the DED nozzle body, the AM apparatus further having a first pipe, a separation wall extending from the end of the first pipe toward the upstream side inside the first pipe, and a plurality of second pipes connected to the end of the first pipe, the separation wall dividing the end of the first pipe into a plurality of regions, each of the plurality of second pipes being connected to each of the plurality of regions of the first pipe, and the second pipes being connected to the powder passage of the DED nozzle. [Brief explanation of the drawing]

[0006] [Figure 1] This figure schematically shows an AM (Additive Manufacturing) apparatus for manufacturing molded objects according to one embodiment. [Figure 2] This figure schematically shows a cross-section of a DED nozzle according to one embodiment. [Figure 3] This is a schematic cross-sectional view showing the piping of a powder supply mechanism, based on one example. [Figure 4] This is a schematic cross-sectional view showing the piping of a powder supply mechanism, based on one example. [Figure 5A] This is a schematic cross-sectional view showing the piping of a powder supply mechanism according to one embodiment. [Figure 5B] This is a cross-sectional perspective view taken at position 5B shown in Figure 5A. [Figure 5C] This is a cross-sectional perspective view taken at position 5C shown in Figure 5A. [Figure 5D] This is a cross-sectional perspective view taken at position 5D shown in Figure 5A. [Figure 6A] This is a schematic cross-sectional view showing the piping of a powder supply mechanism according to one embodiment. [Figure 6B] This is a cross-sectional perspective view taken at position 6B shown in Figure 6A. [Figure 6C] This is a cross-sectional perspective view taken at position 6C shown in Figure 6A. [Figure 6D] This is a cross-sectional perspective view taken at position 6D shown in Figure 6A. [Figure 7A] This is a schematic cross-sectional view showing the piping of a powder supply mechanism according to one embodiment. [Figure 7B] This is a cross-sectional perspective view taken at position 7B shown in Figure 7A. [Figure 7C] This is a cross-sectional perspective view taken at position 7C shown in Figure 7A. [Figure 7D] This is a cross-sectional perspective view taken at position 7D shown in Figure 7A. [Figure 7E] This is a cross-sectional perspective view taken at position 7E shown in Figure 7A. [Modes for carrying out the invention]

[0007] Embodiments of the AM apparatus for manufacturing molded objects according to the present invention will be described below with reference to the accompanying drawings. In the accompanying drawings, identical or similar elements are denoted by identical or similar reference numerals, and redundant descriptions of identical or similar elements may be omitted in the description of each embodiment. Furthermore, the features shown in each embodiment are applicable to other embodiments as long as they do not contradict each other.

[0008] Figure 1 is a schematic diagram of an AM apparatus for manufacturing a molded object according to one embodiment. As shown in Figure 1, the AM apparatus 100 includes a base plate 102. The molded object M will be formed on the base plate 102. The base plate 102 can be a plate formed from any material capable of supporting the molded object M. In one embodiment, the base plate 102 is placed on an XY stage 104. The XY stage 104 is a stage that can move in two orthogonal directions (x direction and y direction) in the horizontal plane. The XY stage 104 may also be connected to a lift mechanism that can move in the height direction (z direction). In another embodiment, the XY stage 104 may be omitted.

[0009] In one embodiment, as shown in Figure 1, the AM apparatus 100 includes a DED head 200. The DED head 200 is connected to a laser source 202, a material powder source 204, and a gas source 206. The DED head 200 has a DED nozzle 250. The DED nozzle 250 is configured to eject lasers, material powders, and gases from the laser source 202, the material powder source 204, and the gas source 206.

[0010] The DED head 200 can be any type, for example, a known DED head can be used. The DED head 200 is connected to a moving mechanism 220 and is configured to be movable. The moving mechanism 220 can be any type, for example, it may be configured to move the DED head 200 along a specific axis such as a rail, or it may consist of a robot that can move the DED head 200 to any position and orientation. In one embodiment, the moving mechanism 220 can be configured to move the DED head 200 along three orthogonal axes.

[0011] As shown in FIG. 1, the AM device 100 according to one embodiment includes a control device 170. The control device 170 is configured to control the operations of various operating mechanisms of the AM device 100, such as the above-described DED head 200 and various operating mechanisms. The control device 170 can be composed of a general computer or a dedicated computer.

[0012] FIG. 2 is a diagram schematically showing a cross section of a DED nozzle 250 according to one embodiment. The DED nozzle 250 according to the illustrated embodiment is a DED nozzle body 259 having a truncated cone shape as a whole. The DED nozzle 250 according to the illustrated embodiment includes a first passage 252 through which a laser 251 passes at the center of the DED nozzle body 259. The laser that has passed through the first passage 252 is emitted from the laser port 252a of the DED nozzle body 259. Further, the DED nozzle body 259 includes a second passage 254 through which a material powder and a carrier gas for transporting the material powder pass outside the first passage 252. The material powder that has passed through the second passage 254 is emitted from the powder port 254a. Furthermore, the DED nozzle body 259 includes a shield gas passage 256 through which a shield gas passes outside the powder passage 254. The shield gas that has passed through the shield gas passage 256 is emitted from the gas port 256a. Note that in one embodiment, the DED nozzle 250 may not include the shield gas passage 256 and the gas port 256a.

[0013] The powder passage 254 is configured such that the material powder discharged from the DED nozzle 250 converges at a position substantially the same as the focusing point 251a of the laser 251. In FIG. 2, the flows of the material powder and the carrier gas are indicated by dashed lines. The carrier gas can be an inert gas such as argon gas or nitrogen gas. It is more desirable to use argon gas, which is heavier than air, as the carrier gas. By using an inert gas as the carrier gas, oxidation can be prevented by covering the molten pool formed by melting the material powder with the inert gas. However, due to the flow of the carrier gas discharged from the powder outlet 254a, the outside air may be entrained. Therefore, the DED nozzle 250 shown in FIG. 2 can prevent the surrounding air from being entrained by supplying the shielding gas at a low speed from the shielding gas passage 256 disposed outside the powder passage 254 through which the powder material and the carrier gas are discharged. By preventing the surrounding air (especially oxygen) from being entrained by the carrier gas, generation of a metal oxide film during shaping can be suppressed, and a molten pool with good wettability can be formed. In FIG. 2, the flow of the shielding gas is indicated by an arrow. The shielding gas can be the same type of gas as the carrier gas.

[0014] In one embodiment, the AM device 100 includes a powder supply mechanism 300. The powder supply mechanism 300 is configured to supply the material powder from the material powder source 204 to the second passage 254 of the DED nozzle 250. In one embodiment, the second passage 254 of the DED nozzle 250 is partitioned into a plurality of regions in the circumferential direction. In that case, it is desirable to supply the material powder uniformly to the plurality of regions of the second passage 254. Also, in one embodiment, the second passage 254 of the DED nozzle 250 may be formed as a single second passage 254 without being partitioned into a plurality of regions. For such a single second passage 254, the powder supply mechanism 300 may be configured to supply the material powder from a plurality of positions in the circumferential direction of the second passage 254.

[0015] Figure 3 is a cross-sectional view showing the piping of a powder supply mechanism 400 according to one example. The piping according to the example in Figure 3 comprises a first pipe 402 connected to a material powder source 204, a plurality of second pipes 450A, 450B connected to a second passage 254 of the DED nozzle 250, and an adapter 470 for connecting the first pipe 402 and the second pipes 450. As shown in Figure 3, the adapter 470 has a branch passage 472 inside. The material powder passing through the first pipe 402 is distributed to the plurality of second pipes 450A, 450B via the adapter 470 and supplied to the DED nozzle 250.

[0016] Figure 4 is a cross-sectional view showing the piping of a powder supply mechanism 400 according to one example. The piping according to the example in Figure 4 includes a first pipe 402 connected to a material powder source 204, and a plurality of second pipes 450A, 450B connected to the second passage 254 of the DED nozzle 250. In the example provided, multiple second pipes 450A and 450B are directly connected to the first pipe 402 without using an adapter 470 as shown in Figure 3.

[0017] In the powder supply mechanism 400 shown in the reference example in Figures 3 and 4, the cross-sectional area of ​​the piping changes abruptly at the branching point where the first piping 402 is distributed to multiple second pipings 450. Specifically, the cross-sectional area increases at the branching point from the first piping 402, and decreases from the branching point to each of the second pipings 450A and 450B. Such a change in cross-sectional area at the branching point can cause unstable vortices to be generated in the carrier gas flowing through the piping, which may prevent the material powder from being distributed evenly to the multiple second pipings 450A and 450B.

[0018] Furthermore, as shown in the reference example in Figure 3, when using an adapter 470 equipped with a branching section, material powder may accumulate on a part of the adapter 470. The material powder accumulated on the adapter 470 may accidentally flow down into either of the second pipes 450A or 450B. In such cases, it may not be possible to distribute the material powder evenly to the multiple second pipes 450A and 450B. In particular, when supplying material powder to the DED nozzle 250 at a low speed, material powder is more likely to accumulate on the adapter 470. Generally, in the DED system, the flow of powder material and carrier gas discharged from the DED nozzle 250 is often designed to be between 30 m / s and 40 m / s. If the carrier gas flow is around 30 m / s to 40 m / s, the risk of powder material accumulating on the adapter 470 is small. However, when using the DED method for printing under conditions where powder material is present in the build area, the powder material and carrier gas may be supplied to the DED nozzle 250 at a low speed to prevent the powder material present in the build area from being blown away. For example, even in the DED method, the flow of powder material and carrier gas discharged from the DED nozzle 250 may be designed to be 10 m / s or less, or 5 m / s or less. It is desirable that the material powder can be supplied stably to the DED nozzle 250 even under such conditions.

[0019] Figure 5A is a cross-sectional view showing the piping of a powder supply mechanism 300 according to one embodiment. The powder supply mechanism 300 shown in Figure 5A comprises a first pipe 302 connected to a material powder source 204, and a plurality of second pipes 350A, 350B connected to the second passage 254 of the DED nozzle 250.

[0020] The first pipe 302 shown in Figure 5A includes a separation wall 306 extending upstream from the downstream end 304 inside the first pipe 302. Figure 5B is a cross-sectional perspective view cut out at position 5B shown in Figure 5A. Figure 5C is a cross-sectional perspective view cut out at position 5C shown in Figure 5A. Figure 5D is a cross-sectional perspective view cut out at position 5D shown in Figure 5A. As shown, the separation wall 306 is formed to bisect the inner flow path of the end 304 of the first pipe 302 into pipes 302A and 302B. In other embodiments, the separation wall 306 may be configured to divide the inner flow path of the end 304 of the first pipe 302 into any region, such as three or four equal parts.

[0021] At position 5C shown in Figure 5A, the pipes 302A and 302B, separated by the separation wall 306, each have a semicircular cross-section. In the illustrated embodiment, the pipes 302A and 302B, separated by the separation wall 306, are formed to gradually become circular in cross-section from position 5C toward the end 304 of the first pipe 302. As shown in the illustration, the pipes 302A and 302B, separated by the separation wall 306, are connected to the second pipes 350A and 350B, respectively, at the end 304 of the first pipe 302.

[0022] In the embodiments shown in Figures 5A to 5D, the sum of the cross-sectional areas of the multiple conduits 302A and 302B separated by the separation wall 306 of the first pipe 302 is approximately equal to the cross-sectional area of ​​the conduit before separation. Let s be the cross-sectional area of ​​the conduit of the first pipe 302 before separation, and separate the first pipe 302. When the flow is divided into n equal parts by the wall 306, the cross-sectional area of ​​each flow path is approximately s / n. Therefore, it is desirable for the thickness of the separation wall 306 to be thin.

[0023] As described above, when the first pipe 302 is divided into multiple flow paths, there is almost no change in the cross-sectional area of ​​the pipe. Therefore, it is possible to suppress the generation of unstable vortices in the carrier gas flowing through the first pipe 302. As a result, the powder material flowing together with the carrier gas in the first pipe 302 can be stably and evenly distributed to the multiple flow paths.

[0024] Figure 6A is a cross-sectional view showing the piping of a powder supply mechanism 300 according to one embodiment. The powder supply mechanism 300 shown in Figure 6A comprises a first pipe 302 connected to a material powder source 204, and four second pipes 350A, 350B, 350C, and 350D connected to the second passage 254 of the DED nozzle 250. However, the second pipe 350D is not shown in Figure 6A.

[0025] The first pipe 302 shown in Figure 6A includes a separation wall 306 extending upstream from the downstream end 304 inside the first pipe 302. Figure 6B is a cross-sectional perspective view cut at position 6B shown in Figure 6A. Figure 6C is a cross-sectional perspective view cut at position 6C shown in Figure 6A. As shown, the separation wall 306 is formed to divide the inner flow path of the end 304 of the first pipe 302 into four equal parts: pipes 302A, 302B, 302C, and 302D. In another embodiment, the separation wall 306 may be configured to divide the inner flow path of the end 304 of the first pipe 302 into any region, such as bisecting or trisecting.

[0026] In the embodiment shown in Figure 6A, the first pipe 302 and a plurality of second pipes 350A, 350B, 350C, and 350D are connected via a transition section 330. As shown in Figure 6A, the downstream end 304 of the first pipe 302 is connected to the upstream end 332 of the transition section 330, and the upstream ends 352A, 352B, 352C, and 352D of the second pipes 350A, 350B, 350C, and 350D are connected to the downstream ends 334A, 334B, 334C, and 334D of the transition section 330. As shown in the figure, the transition section 330 includes a transition section separation wall 336 connected to the separation wall 306 of the first pipe 302. In other words, the separation wall 306 of the first pipe 302 extends to the transition section 330, and the separation wall 306 extended to the transition section 330 is referred to as the transition section separation wall 336. Figure 6D is a cross-sectional perspective view cut out at position 6D shown in Figure 6A. As shown, the transition section 330 is divided into four flow paths 330A, 330B, 330C, and 330D by the transition section separation wall 336, and each flow path 330A, 330B, 330C, and 330D is connected to the second pipe 350A, 350B, 350C, and 350D, respectively.

[0027] In the embodiments shown in Figures 6A to 6D, the first pipe 302 is divided by a separation wall 306 into four sector-shaped pipes 302A, 302B, 302C, and 302D. In the illustrated embodiments, the pipes 302A, 302B, 302C, and 302D, all with the same sector-shaped cross-section, continue all the way to the end 304 of the first pipe 302. In the illustrated embodiments, at the upstream end 332 of the transition section 330, the cross-sections of each pipe 330A, 330B, 330C, and 330D are sector-shaped, but towards the downstream end 334A, 334B, 334C, and 334D, the cross-sections deform to become closer to circular.

[0028] In the embodiments shown in Figures 6A to 6D, the sum of the cross-sectional areas of the multiple conduits divided by the separation wall 306 inside the first pipe 302 is approximately equal to the cross-sectional area of ​​the conduit before division. If the cross-sectional area of ​​the conduit in the first pipe 302 before division is s, and the first pipe 302 is divided into n equal parts by the separation wall 306, the cross-sectional area of ​​each conduit is approximately s / n. Therefore, it is desirable for the thickness of the separation wall 306 to be thin.

[0029] In the embodiments shown in Figures 6A to 6D, the cross-sectional area of ​​the flow path changes at the transition section 330. However, since the flow path is already divided into multiple sections by the separation wall 306 upstream of the end 304 of the first pipe 302, the distribution of the material powder is already carried out by the separation wall 306 of the first pipe 302. Therefore, it is possible to suppress the non-uniform distribution of the material powder due to turbulence in the carrier gas flow caused by the change in the cross-sectional area of ​​the flow path at the transition section 330.

[0030] Figure 7A is a cross-sectional view showing the piping of a powder supply mechanism 300 according to one embodiment. The powder supply mechanism 300 shown in Figure 7A comprises a first pipe 302 connected to a material powder source 204, and four second pipes 350A, 350B, 350C, and 350D connected to the second passage 254 of the DED nozzle 250.

[0031] The first pipe 302 shown in Figure 7A includes a separation wall 306 extending upstream from the downstream end 304 towards the inside of the first pipe 302. Figure 7B is a cross-sectional perspective view cut out at position 7B shown in Figure 7A. Figure 7C is a cross-sectional perspective view cut out at position 7C shown in Figure 7A. Figure 7D is a cross-sectional perspective view cut out at position 7D shown in Figure 7A.

[0032] As shown in Figures 7A and 7C, the separation wall 306 of the first pipe 302 divides the flow path of the first pipe 302 into two equal parts at position 7C, which is the upstream end of the separation wall 306. Then, as shown in Figures 7A and 7D, the two divided flow paths are further divided into two equal parts at position 7D, which is an intermediate position of the separation wall 306. As shown in the figures, in this embodiment, the first pipe 302 is divided into four pipes 302A, 302B, 302C, and 302D at end 304. In another embodiment, the separation wall 306 of the first pipe 302 may be formed to arbitrarily divide the flow path into n parts upstream, and further arbitrarily divide the flow path into m parts at an intermediate position, so that the flow path at end 304 of the first pipe 302 is divided into a total of n × m sections. Hereinafter, n and m are natural numbers of 2 or greater.

[0033] In the embodiment shown in Figure 7A, the first pipe 302 and the multiple second pipes 350A, 350B, 350C, and 350D are connected via a transition section 330. Figure 7E is a cross-sectional perspective view taken at position 7E shown in Figure 7A. The configuration of the transition section 330 is the same as in the embodiments shown in Figures 6A to 6D, so a description is omitted.

[0034] In the embodiments shown in Figures 7A to 7E, the sum of the cross-sectional areas of the multiple conduits divided by the separation wall 306 inside the first pipe 302 is approximately equal to the cross-sectional area of ​​the conduit before division. If the cross-sectional area of ​​the conduit of the first pipe 302 before division is s, and the first pipe 302 is divided into n equal parts by the separation wall 306 at the end 304, the cross-sectional area of ​​each conduit is approximately s / n. Therefore, it is desirable for the thickness of the separation wall 306 to be thin.

[0035] In the embodiments shown in Figures 7A to 7E, the cross-sectional area of ​​the flow path changes at the transition section 330. However, since the flow path is already divided into multiple sections by the separation wall 306 upstream of the end 304 of the first pipe 302, the distribution of the material powder is already performed by the separation wall 306 of the first pipe 302. Therefore, it is possible to suppress the non-uniform distribution of the material powder caused by turbulence in the carrier gas flow due to the change in the cross-sectional area of ​​the flow path at the transition section 330. In the embodiments shown in Figures 7A to 7E, unlike the embodiments shown in Figures 6A to 6D, the flow path is divided in two stages at the upstream end and intermediate position of the separation wall 306. Compared to the case where the flow path is divided into many sections at once, the area of ​​the end of the separation wall 306 into which the material powder collides is reduced, and the variation in the distribution of the material powder can be further reduced.

[0036] In any of the embodiments described above, the separation wall 306 of the first pipe 302 has a length extending upstream from the downstream end 304 of the first pipe 302, when the diameter of the first pipe 302 is φ. It is desirable that the configuration be such that the value is greater than or equal to φ.

[0037] In one embodiment, the first pipe 302, the second pipe 350, and the transition section 330, which are equipped with the separation wall 306 described above, can be formed from the same type of material as the material powder supplied to the AM device. For example, the first pipe 302, the second pipe 350, and the transition section 330 can be formed from a metal material or a resin material. In one embodiment, the first pipe 302, the second pipe 350, and the transition section 330 can be formed from SUS. In another embodiment, it is desirable that the first pipe 302, the second pipe 350, and the transition section 330, which are equipped with the separation wall 306, be formed from a conductive material to prevent static charge buildup. For example, these components can be formed from a conductive resin material or a metal material. Furthermore, it is desirable that these materials be used in an electrically grounded state in the AM device.

[0038] In one embodiment, the first pipe 302, the second pipe 350, and the transition section 330 are formed by a known AM method. By manufacturing the first pipe 302, the second pipe 350, and the transition section 330 by the AM method, the connecting parts of each pipe and the shape changes of the transition section can be smoothly formed.

[0039] At least the following technical concepts can be understood from the embodiments described above. [Embodiment 1] According to Embodiment 1, an AM apparatus for manufacturing molded objects is provided, the AM apparatus having a DED nozzle, the DED nozzle having a powder port provided at the tip of the DED nozzle body for ejecting powder material, and a powder passage communicating with the powder port for the powder material to pass through the DED nozzle body, the AM apparatus further having a first pipe, a separation wall extending from the end of the first pipe toward the upstream side inside the first pipe, and a plurality of second pipes connected to the end of the first pipe, the separation wall dividing the end of the first pipe into a plurality of regions, each of the plurality of second pipes being connected to each of the plurality of regions of the first pipe, and the second pipes being connected to the powder passage of the DED nozzle.

[0040] [Form 2] According to Form 2, in the AM device according to Form 1, when the inner diameter of the first pipe is φ, the length of the separation wall extending upstream from the end of the first pipe is greater than φ.

[0041] [Embodiment 3] According to Embodiment 3, in an AM device according to Embodiment 1 or 2, the separation wall of the first pipe has a first separation wall that evenly divides the inside of the first pipe into a plurality of regions, and a second separation wall that further divides each region evenly divided by the first separation wall into a plurality of regions.

[0042] [Form 4] According to Form 4, in an AM device according to any one of Forms 1 to 3, the first pipe and the second pipe are connected via a transition section, the transition section has a transition section separation wall connected to the separation wall of the first pipe, the transition section is divided into a plurality of regions by the transition section separation wall, and each of the plurality of second pipes is connected to each of the plurality of regions of the transition section.

[0043] [Form 5] According to Form 5, in the AM device according to Form 4, when the inner cross-sectional area of ​​the first pipe is s and the number of compartments at the end of the first pipe is n, the cross-sectional area of ​​each of the compartments in the branch section is approximately s / n.

[0044] [Form 6] According to Form 6, in an AM device according to any one of Forms 1 to 5, the powder material and carrier gas are discharged from the powder port of the DED nozzle at a flow rate of 10 m / s or less. [Explanation of Symbols]

[0045] 100…AM device 200... Head 202... Laser source 204…Material powder source 206... Gas source 250... Nozzle 252…1st aisle 254…Second aisle 300...Powder supply mechanism 302...First piping 304...End 306…Separation wall 330...Transition part 332...end 336…Transition part separation wall 350...Second piping M…modeled object

Claims

1. AM apparatus for manufacturing molded objects, wherein the AM apparatus is It has a DED nozzle, and the DED nozzle is The DED nozzle body has a plurality of powder ports provided at its tip for ejecting powder material, and a plurality of powder passages communicating with each of the plurality of powder ports for the powder material to pass through inside the DED nozzle body. The AM device further, First piping and A separation wall extending from the end of the first pipe toward the upstream side inside the first pipe, It comprises a plurality of second pipes connected to the end of the first pipe, The separation wall divides the end of the first pipe into a plurality of regions, and each of the plurality of second pipes is connected to each of the plurality of regions of the first pipe. Each of the plurality of second pipes is connected to each of the plurality of powder passages of the DED nozzle, Each of the plurality of compartments of the first piping, partitioned by the separation wall, has a uniform cross-sectional area from the upstream end of the separation wall to the end of the first piping. AM device.

2. AM apparatus according to claim 1, When the inner diameter of the first pipe in the region where the separation wall is provided is φ, the separation wall has a length greater than φ extending upstream from the end of the first pipe. AM device.

3. AM apparatus according to claim 1 or 2, The separation wall of the first pipe described above is A first separation wall that evenly divides the inside of the first pipe into multiple regions, The device comprises a second separation wall that further divides each region evenly partitioned by the first separation wall into a plurality of regions, AM device.

4. AM apparatus according to any one of claims 1 to 3, The first pipe and the second pipe are connected via a transition section. The transition section has a transition section separation wall connected to the separation wall of the first pipe, the transition section is divided into a plurality of regions by the transition section separation wall, and each of the plurality of second pipes is connected to each of the plurality of regions of the transition section. AM device.

5. AM apparatus according to claim 4, Let s be the inner cross-sectional area of ​​the first pipe in the region before it is partitioned by the separation wall, and let n be the number of compartments at the end of the first pipe. Then, the cross-sectional area of ​​each of the compartments at the end is approximately s / n. AM device.

6. AM apparatus according to any one of claims 1 to 5, The DED nozzle is configured such that the powder material and carrier gas are discharged from the powder port at a flow rate of 10 m / s or less. AM device.

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