Apparatus for powder bed fusion

Abstract

Apparatus for powder bed fusion. An apparatus includes a wall defining a shaft, a powder platform configured to support a powder bed within the shaft and configured to move through the shaft, and a sealing device in compression from an outer periphery of the sealing device to an inner periphery of the sealing device such that the outer periphery contacts the wall and the inner periphery contacts the powder platform to form a seal between the powder platform and the wall. Another apparatus includes a wall defining a shaft, a powder platform configured to support a powder bed within the shaft and configured to move through the shaft, and a sealing device including a non-fibrous material attached to and extending away from the powder platform, the sealing device contacting the wall to form a seal between the powder platform and the wall.

Description

Technical Field

[0001] This disclosure generally relates to apparatus and methods for powder bed fusion, and more specifically, to apparatus and methods for powder bed fusion, which relate to sealing devices. Background Technology

[0002] Powder bed fusion is an additive manufacturing technique that typically involves using a laser beam or electron beam to form rigid components (e.g., aircraft components) from a powder bed of a material such as a metal. The beam is selectively scanned over an exposed area of ​​the powder bed to sinter the powder at desired locations, thereby forming the desired profile of the component. Subsequently, a powder platform supporting the powder bed is lowered, additional powder is provided on top of the powder bed, and the beam is used to form the profile at a higher level of the component, and so on.

[0003] Fiber materials such as braided nylon rings are often used to form a basic seal between the powder bed and the shaft, surrounding the powder bed and powder platform. However, loose powder tends to fall through the rings and onto the powder bed, which typically requires periodic removal of the powder from under the powder bed. Additionally, friction between the rings and the shaft can cause the rings to detach fibers onto the powder bed, which can contaminate and damage the components being formed by the equipment. Therefore, a powder bed fusion apparatus is needed that better prevents loose powder from migrating to unwanted areas and reduces or eliminates foreign material falling into the components being formed. Summary of the Invention

[0004] One aspect of this disclosure is an apparatus for powder bed fusion, the apparatus comprising: a wall defining a shaft; a powder platform configured to support a powder bed within the shaft and configured to move through the shaft; and a sealing device compressed from its outer periphery to its inner periphery, such that the outer periphery contacts the wall and the inner periphery contacts the powder platform to form a seal between the powder platform and the wall.

[0005] Another aspect of this disclosure is an apparatus for powder bed fusion, the apparatus comprising: a wall defining a shaft; a powder platform configured to support a powder bed within the shaft and configured to move through the shaft; and a sealing device comprising a non-fibrous material attached to and extending away from the powder platform, the sealing device contacting the wall to form a seal between the powder platform and the wall.

[0006] Another aspect of this disclosure is a method for performing powder bed fusion, the method comprising: providing a powder bed supported by a powder platform within a shaft defined by a wall; selectively sintering a portion of an exposed layer of the powder bed; and moving the powder platform downward within the shaft while a sealing device maintains a seal between the powder platform and the wall, the sealing device being compressed from the outer periphery of the contact wall of the sealing device to the inner periphery of the contact powder platform of the sealing device.

[0007] Another aspect of this disclosure is a method for performing powder bed fusion, the method comprising: providing a powder bed supported by a powder platform within a shaft defined by a wall; selectively sintering a portion of an exposed layer of the powder bed; and moving the powder platform downward within the shaft while a sealing device maintains a seal between the powder platform and the wall, the sealing device comprising a non-fibrous material attached to and extending away from the powder platform.

[0008] The terms “about” or “substantially” used to describe reference quantities or measurements in this document mean that the characteristic, parameter, or value does not need to be precisely achieved, but rather that deviations or variations in quantity do not prevent the effect that the characteristic is intended to provide, including, for example, tolerances, measurement errors, measurement accuracy limitations, and other factors known to those skilled in the art.

[0009] The features, functions, and advantages discussed can be implemented independently in various examples or combined in other examples, further details of which can be seen in the following description and figures. Attached Figure Description

[0010] Novel features considered exemplary are set forth in the appended claims. However, the exemplary features, preferred modes of use, further objectives, and their descriptions will be best understood, when read in conjunction with the accompanying drawings, by referring to the following detailed description of the exemplary features of this disclosure.

[0011] Figure 1 It is a cross-sectional view of the device based on the example.

[0012] Figure 2 It is a 3D diagram of the device in the example.

[0013] Figure 3 It is an exploded view of the device based on the example.

[0014] Figure 4 It is a 3D diagram of the device in the example.

[0015] Figure 5 It is an exploded view of the device based on the example.

[0016] Figure 6 It is a cross-sectional view of the device in the example.

[0017] Figure 7 It is a 3D diagram of the device in the example.

[0018] Figure 8 It is an exploded view of the device based on the example.

[0019] Figure 9 It is a 3D diagram of the device in the example.

[0020] Figure 10 It is an exploded view of the device based on the example.

[0021] Figure 11 It is a flowchart based on the example method.

[0022] Figure 12 It is a flowchart based on the example method. Detailed Implementation

[0023] As described above, there is a need for a powder bed fusion apparatus that better prevents loose powder from migrating to unwanted areas and reduces or eliminates foreign material falling into the component being formed. In this example, the apparatus for powder bed fusion includes: a wall defining a shaft; a powder platform configured to support a powder bed (e.g., powdered metal) within the shaft and configured to move through the shaft; and a sealing device compressed from its outer periphery to its inner periphery, such that the outer periphery contacts the wall and the inner periphery contacts the powder platform to form a seal between the powder platform and the wall.

[0024] In another example, the apparatus for powder bed fusion includes: a wall defining a shaft; a powder platform configured to support the powder bed within the shaft and configured to move through the shaft; and a sealing device comprising a non-fibrous material (e.g., a metal coated with a solid lubricant) attached to and extending away from the powder platform, the sealing device contacting the wall to form a seal between the powder platform and the wall.

[0025] Compared to conventional equipment used for powder bed fusion, the above-mentioned equipment is better able to prevent loose powder from migrating to unwanted areas and can reduce or eliminate foreign material falling into the forming component.

[0026] The disclosed examples will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, of the disclosed examples. In fact, several different examples may be described and should not be construed as limited to the examples set forth herein. Rather, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of this disclosure to those skilled in the art.

[0027] Figures 1 to 10 This is a schematic diagram of device 100 and its related functions.

[0028] Figure 1This is a cross-sectional view of an apparatus 100 for powder bed fusion. The apparatus 100 includes a wall 102 defining a shaft 104. The apparatus 100 also includes a powder platform 106 configured to support a powder bed 108 within the shaft 104 and configured to move through the shaft 104. The apparatus 100 also includes a sealing device 110 compressed from its outer periphery 112 to its inner periphery 114, such that the outer periphery 112 contacts the wall 102 and the inner periphery 114 contacts the powder platform 106 to form a seal 116 between the powder platform 106 and the wall 102.

[0029] The wall 102 may be formed of metal, but other materials are also possible. In the example described below, the wall 102 wholly or partially defines the shaft 104. That is, the wall 102 forms the periphery of the shaft 104. In the example described below, the shaft 104 may have a rectangular shape, a square shape, or a circular shape.

[0030] The powder platform 106 is also typically formed of metal. The powder platform 106 supports the powder bed 108 during assembly formation from the powder bed 108. The powder platform 106 includes a body 136, a first member 138 extending toward the wall 102 and away from the body 136, and a second member 140 extending toward the wall 102 and away from the body 136 further than the first member 138. The body 136, the first member 138, and the second member 140 form a pocket or cavity into which a sealing device 110 (e.g., an inner periphery 114) engages.

[0031] Powder bed 108 typically comprises powdered metal, but other examples are also possible. Sections of powder bed 108 are selectively sintered layer by layer using a laser or electron beam to form components (e.g., aircraft components). This process is described in more detail below.

[0032] The sealing device 110 may be formed of a flexible or elastic metal. That is, the sealing device 110 may return to its original (e.g., relaxed) shape after being deformed to fit between the wall 102 and the powder platform 106. Figure 1 In this configuration, the sealing device 110 is compressed and applies a force 128 to the wall 102 via the outer periphery 112 and a force 128 to the powder platform 106 via the inner periphery 114. The sealing device 110 acts as a gasket forming a seal 116 between the powder platform 106 and the wall 102. The seal 116 substantially prevents a significant amount of powder bed 108 from falling between the wall 102 and the powder platform 106 (e.g., as the powder platform 106 moves up and down).

[0033] The sealing device 110 includes a first arm 142 that contacts the first member 138, a second arm 144 that contacts the wall 102, and a base 146 that connects the first arm 142 and the second arm 144 and contacts the second member 140. When the sealing device 110 is in a compressed state, the first arm 142 bends toward the second arm 144 and the sealing device 110 stores mechanical energy. For example, the dimensions of the powder platform 106 (e.g., body 136, first member 138, and / or second member 140) may require the sealing device 110 to be in a compressed state to fit between the first member 138, the second member 140, and the wall 102, such as... Figure 1 As shown. The compression state may include any condition under which the sealing device 110 experiences compressive force and / or expansion force is applied to the powder platform 106 and / or the wall 102.

[0034] The outer periphery 112 includes a non-fibrous surface 118 that contacts the wall 102. A solid lubricant coating (e.g., polytetrafluoroethylene) may be formed on the exterior of the sealing device 110, forming the non-fibrous surface 118. The outer periphery 112 is substantially conformable to the wall 102.

[0035] The portion 213 of the powder bed 108 located between the first arm 142 and the second arm 144 will generally contribute to the force 128 and form a more effective seal 116 by gravity, as the first arm 142 and the second arm 144 are forced away from each other. The portion 215 of the powder bed 108 located above the sealing device 110 will also contribute to the force 128.

[0036] Figure 2 This is a perspective view of device 100. As shown, device 100 also includes a second wall 122, a third wall 124, and a fourth wall 126. Shaft 104 has a rectangular shape (e.g., a square shape) defined by walls 102, the second wall 122, the third wall 124, and the fourth wall 126. In applications where device 100 is used to form components having rectangular symmetry or shapes, it may be useful for walls 102, the second wall 122, the third wall 124, and the fourth wall 126 (e.g., shaft 104) to also have rectangular symmetry and / or shapes.

[0037] exist Figure 2 In the diagram, the powder platform 106 is shown in dashed lines, and walls 102, 122, 124, and 126 are transparent, making the sealing device 110 easier to identify. Only the exposed layer 352 of the powder bed 108 is shown. Figure 2 In this configuration, the sealing device 110 has a square or rectangular shape substantially conforming to the walls 102, 122, 124, and 126. Specifically, the outer periphery 112 abuts against the walls 102, 122, 124, and 126 to form a seal 116. The piston 107 is used to move the powder platform 106 up and down through the shaft 104 as needed.

[0038] Figure 3 This is an exploded view of equipment 100.

[0039] Figure 4 This is a perspective view of device 100, depicting an example where device 100, wall 102, and shaft 104 are all circular in shape. Figure 4 In the diagram, the powder platform 106 is shown in dashed lines and the wall 102 is transparent, making the sealing device 110 easier to identify. Additionally, only the exposed layer 352 of the powder bed 108 is shown. Figure 4 In this embodiment, the sealing device 110 has a circular shape that is substantially conformable to the wall 102. That is, the outer periphery 112 abuts against the wall 102 to form a seal 116. In applications where the device 100 is used to form components with rotational symmetry, it may be useful for the wall 102 (e.g., shaft 104) to have a circular shape and / or rotational symmetry.

[0040] Figure 5 yes Figure 4 An exploded view of the device 100 shown.

[0041] Figure 6 This is a cross-sectional view of an apparatus 200 for powder bed fusion. The apparatus 200 includes a wall 102 defining a shaft 104. The apparatus 200 also includes a powder platform 206 configured to support a powder bed 108 within the shaft 104 and configured to move through the shaft 104. The apparatus 200 also includes a sealing device 210 comprising a non-fibrous material attached to and extending away from the powder platform 206. The sealing device 210 contacts the wall 102 to form a seal 216 between the powder platform 206 and the wall 102.

[0042] Powder platform 206 may include one or more features of powder platform 106, however powder platform 206 may have a different shape than powder platform 106 as shown.

[0043] Sealing device 210 may include one or more features of sealing device 110; however, sealing device 210 may have a different shape than sealing device 110 as shown. Sealing device 210 comprises and / or is formed of a non-fibrous material such as metal and may be coated with a solid lubricant such as polytetrafluoroethylene. In other examples, the non-fibrous material is a foam material or graphite.

[0044] Sealing device 210 acts as a gasket forming a seal 216 between powder platform 206 and wall 102. Seal 216 substantially prevents a significant amount of powder bed 108 from falling between wall 102 and powder platform 206 (e.g., as powder platform 206 moves up and down). Sealing device 210 is configured to scrape powder 154 accumulated on wall 102 away from wall 102 (e.g., in the case where powder platform 206 moves downward through shaft 104). For example, as powder platform 206 moves downward, second arm 150 can move against wall 102, thereby forcing powder 154 away from wall 102 and downward through shaft 104. In some examples, powder 154 is completely separated from wall 102 by second arm 150 and falls downward through shaft 104.

[0045] The sealing device 210 includes a first arm 148 that contacts the powder platform 206. As shown, the first arm 148 is bolted to the powder platform 206. The sealing device 210 also includes a second arm 150 that contacts the wall 102 and a tip 152 that connects the first arm 148 and the second arm 150 and is configured to scrape powder 154 accumulated on the wall 102 away from the wall 102.

[0046] The portion 213 of the powder bed 108 located between the first arm 148 and the second arm 150 will contribute to force 128 and form a more effective seal 216 by substantially gravity-forced movement of the first arm 148 and the second arm 150 away from each other. The portion 215 of the powder bed 108 located above the sealing device 210 will also contribute to force 128.

[0047] The sealing device 210 (e.g., the first arm 148) is secured to the powder platform 206 via one or more bolts 212.

[0048] Figure 7 This is a perspective view of device 200. As shown, device 200 also includes a second wall 122, a third wall 124, and a fourth wall 126. Shaft 104 has a rectangular shape (e.g., a square shape) defined by wall 102, second wall 122, third wall 124, and fourth wall 126.

[0049] exist Figure 7 In the diagram, the bottom of the powder platform 206 is shown in dashed lines, and walls 102, 122, 124, and 126 are transparent, making the sealing device 210 easier to identify. Additionally, only the exposed layer 352 of the powder bed 108 is shown. Figure 7In this configuration, the sealing device 210 has a square or rectangular shape substantially conforming to the walls 102, 122, 124, and 126. Specifically, the second arm 150 abuts against the walls 102, 122, 124, and 126 to form a seal 216. The piston 107 is used to move the powder platform 206 up and down through the shaft 104 as needed.

[0050] Figure 8 This is an exploded view of equipment 200.

[0051] Figure 9 This is a perspective view of device 200, depicting an example where device 200, wall 102, and shaft 104 are all circular in shape. Figure 9 In the image, the bottom of the powder platform 206 is shown in dashed lines and the wall 102 is transparent, making the sealing device 210 easier to identify. Additionally, only the exposed layer 352 of the powder bed 108 is shown. Figure 9 In this configuration, the sealing device 210 has a circular shape that is substantially conformable to the wall 102. That is, the second arm 150 abuts against the wall 102 to form a seal 116.

[0052] Figure 10 yes Figure 9 An exploded view of device 200 shown.

[0053] Figure 11 and Figure 12 This is a block diagram of methods 300 and 400 for performing powder bed fusion. Methods 300 and 400 present methods that can be used with... Figures 1 to 10 An example of a method for using device 100 or device 200 together. For example... Figure 11 and Figure 12 As shown, methods 300 and 400 include one or more operations, functions, or actions as indicated by blocks 302, 304, 306, 402, 404, and 406. Although the blocks are shown sequentially, they may also be executed in parallel and / or in an order different from that described herein. Furthermore, depending on the desired implementation, the various blocks may be combined into fewer blocks, divided into additional blocks, and / or removed.

[0054] In block 302, method 300 includes providing a powder bed 108 supported by a powder platform 106 within a shaft 104 defined by a wall 102. This function is illustrated above, for example... Figures 1 to 5 It has been described.

[0055] In block 304, method 300 includes selectively sintering portions of the exposed layer 352 of the powder bed 108. For example, an electron beam or laser can be used to selectively sinter... Figures 2 to 5 The exposed layer 352 shown is partially sintered.

[0056] In block 306, method 300 includes moving the powder platform 106 downward within shaft 104 while maintaining a seal 116 between the sealing device 110 and the wall 102. The sealing device 110 is compressed from the outer periphery 112 of the sealing device 110 contacting the wall 102 to the inner periphery 114 of the sealing device 110 contacting the powder platform 106. For example, a piston 107 can be used to lower the pressure. Figures 1 to 5 The powder platform 106 shown.

[0057] In block 402, method 400 includes providing a powder bed 108 supported by a powder platform 206 within a shaft 104 defined by a wall 102. This function is illustrated above, for example... Figures 6 to 10 It has been described.

[0058] In block 404, method 400 includes selectively sintering portions of the exposed layer 352 of the powder bed 108. For example, an electron beam or laser can be used to selectively sinter... Figures 7 to 10 The exposed layer 352 shown is partially sintered.

[0059] In block 406, method 400 includes moving the powder platform 206 downward within the shaft 104 while maintaining a seal 216 between the sealing device 210 and the wall 102. The sealing device 210 comprises a non-fibrous material attached to and extending away from the powder platform 206. For example, a piston 107 may be used to lower the powder platform 206. Figures 6 to 10 The powder platform 206 shown.

[0060] Examples of this disclosure may therefore relate to one of the enumerated terms (EC) listed below.

[0061] EC 1 is an apparatus for powder bed fusion, the apparatus comprising: a wall defining a shaft; a powder platform configured to support a powder bed within the shaft and configured to move through the shaft; and a sealing device under compression from its outer periphery to its inner periphery, such that the outer periphery contacts the wall and the inner periphery contacts the powder platform to form a seal between the powder platform and the wall.

[0062] EC 2 is the device according to EC 1, wherein the sealing device includes a non-fibrous surface of the outer peripheral contact wall.

[0063] EC 3 is the device according to EC 2, wherein the non-fibrous surface comprises a solid lubricant.

[0064] EC 4 is the device according to any one of EC 1-3, wherein the wall has a substantially circular shape.

[0065] EC 5 is an apparatus according to any one of EC 1-3, wherein the wall is a first wall, the apparatus further includes a second wall, a third wall and a fourth wall, and the shaft has a rectangular shape defined by the first wall, the second wall, the third wall and the fourth wall.

[0066] EC 6 is an apparatus according to any one of EC 1-5, wherein the sealing device applies force to the powder platform via the outer periphery against the wall and via the inner periphery.

[0067] EC 7 is a device according to any one of EC 1-6, wherein the outer periphery is substantially conformable to the wall.

[0068] EC 8 is an apparatus according to any one of EC 1-7, wherein the powder platform includes: a body; a first member extending toward a wall and away from the body; and a second member extending toward the wall and away from the body further than the first member, and wherein the sealing device includes: a first arm contacting the first member; a second arm contacting the wall; and a base connecting the first arm and the second arm and contacting the second member.

[0069] EC 9 is the device according to EC 8, wherein the portion of the powder bed located between the first arm and the second arm forces the first arm and the second arm away from each other.

[0070] EC 10 is an apparatus for powder bed fusion, the apparatus comprising: a wall defining a shaft; a powder platform configured to support a powder bed within the shaft and configured to move through the shaft; and a sealing device comprising a non-fibrous material attached to and extending away from the powder platform, the sealing device contacting the wall to form a seal between the powder platform and the wall.

[0071] EC 11 is the device according to EC 10, wherein the sealing device includes: a first arm that contacts a powder platform; a second arm that contacts a wall; and a tip that connects the first arm and the second arm and is configured to scrape powder accumulated on the wall away from the wall.

[0072] EC 12 is the device according to EC 11, wherein the portion of the powder bed located between the first arm and the second arm forces the first arm and the second arm away from each other.

[0073] EC 13 is the device according to any one of EC 10-12, wherein the non-fibrous material includes foam material.

[0074] EC 14 is an apparatus according to any one of EC 10-13, wherein the non-fibrous material includes graphite.

[0075] EC 15 is a device according to any one of EC 10-14, wherein the sealing device has a periphery that is substantially conformal to the wall.

[0076] EC 16 is a device according to any one of EC 10-15, wherein the non-fibrous material includes a solid lubricant.

[0077] EC 17 is a device according to any one of EC 10-16, wherein the walls have a substantially circular shape.

[0078] EC 18 is a device according to any one of EC 10-16, wherein the wall is a first wall, the device further includes a second wall, a third wall and a fourth wall, and the shaft has a rectangular shape defined by the first wall, the second wall, the third wall and the fourth wall.

[0079] EC 19 is an apparatus according to any one of EC 10-18, wherein the sealing device is configured to scrape powder accumulated on the wall away from the wall.

[0080] EC 20 is a method for performing powder bed fusion, the method comprising: providing a powder bed supported by a powder platform within a shaft defined by a wall; selectively sintering a portion of an exposed layer of the powder bed; and moving the powder platform downward within the shaft while a sealing device maintains a seal between the powder platform and the wall, the sealing device being compressed from the outer periphery of the contact wall of the sealing device to the inner periphery of the contact powder platform of the sealing device.

[0081] Various advantageous arrangements have been described for illustrative and descriptive purposes and are not intended to be exhaustive or limited to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. Furthermore, different advantageous examples may describe different advantages compared to other advantageous examples. The selected examples have been chosen and described to illustrate the principles of the examples, their practical application, and to enable those skilled in the art to understand the various examples of this disclosure and the various modifications suitable for particular uses that may be conceived.

Claims

1. An apparatus (100) for powder bed fusion, the apparatus comprising: Wall (102), which defines the axis (104); Powder platform (106), configured to support a powder bed (108) within the shaft and configured to move through the shaft, the powder platform comprising: Main body (136); A first member (138) extending toward the wall (102) and away from the body (136); and A second member (140) extending further than the first member (138) toward the wall (102) and away from the body (136), wherein the body (136), the first member (138), and the second member (140) form a cavity; and A sealing device (110) is compressed from its outer periphery (112) to its inner periphery (114), such that the outer periphery contacts the wall and the inner periphery contacts the powder platform to form a seal (116) between the powder platform and the wall, wherein the sealing device (110) is positioned in the cavity. The sealing device (110) includes: The first arm (142) contacts the first component (138) and is located within the cavity; The second arm (144) that contacts the wall (102); and Connect the first arm (142) and the second arm (144) and contact the base (146) of the second member (140). The portion of the powder bed (108) located between the first arm (142) and the second arm (144) applies a first force to the first arm (142) pointing toward the powder platform (106) and a second force to the second arm (144) pointing toward the wall (102).

2. The device according to claim 1, wherein, The sealing device includes a non-fibrous surface (118) that contacts the wall on the outer periphery.

3. The device according to claim 2, wherein, The non-fibrous surface includes a solid lubricant.

4. The device according to claim 1, wherein, The wall has a substantially circular shape.

5. The device according to claim 1, wherein, The wall is a first wall, and the device also includes a second wall (122), a third wall (124) and a fourth wall (126), and the shaft has a rectangular shape defined by the first wall, the second wall, the third wall and the fourth wall.

6. The device according to claim 1, wherein, The sealing device applies a force (128) to the wall via the outer periphery and a force (128) to the powder platform via the inner periphery.

7. The device according to claim 1, wherein, The outer periphery is substantially conformable to the wall.

8. The device according to claim 1, wherein, The sealing device is configured to scrape powder accumulated on the wall away from the wall.

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