Tuning support geometry for additive manufacturing support removal and method of use thereof

Abstract

Systems and methods of forming and removing a support structure formed in a powder bed melting (PBF) system are provided. The support structure is formed with a specified failure zone designed to fail in a controlled manner when resonated by the one or more resonating devices.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 414,854, filed on Oct. 10, 2022, entitled “DYNAMICALLY TUNED LOCAL SUPPORT GEOMETRIES FOR COMBINED POWDER AND SUPPORT REMOVAL” and U.S. Non - Provisional Application No. 18 / 484,319, filed on Oct. 10, 2023, entitled “TUNED SUPPORT GEOMETRIES FOR ADDITIVE MANUFACTURING SUPPORT REMOVAL AND METHODS OF USE THEREOF”, the entire contents of which are incorporated herein by reference. Field of the Invention

[0003] The present disclosure generally relates to additive manufacturing, and more particularly, to the formation and removal of support structures for additive manufacturing. Background Art

[0004] Additive manufacturing (AM) systems can produce metal structures (referred to as build parts) having geometrically complex shapes, including some shapes that are difficult or impossible to generate using traditional manufacturing processes. (AM) techniques are used to generate build parts layer - by - layer (i.e., slice - by - slice). Each layer or slice can be formed by a process of depositing a layer of metal powder and melting (e.g., adhering and / or melting and cooling) the regions of the additive material that correspond to the cross - section of the build part in that layer. This process can be repeated to form the next slice of the build part, and so on. Since each layer is deposited on the previous layer, AM can be likened to forming a structure slice - by - slice and allows the formation of structures that were previously impossible to form using traditional machining (i.e., subtractive manufacturing) techniques.

[0005] The shapes of some build parts may cause undesirable results in the finished part. For example, some shapes include overhangs or other structures that require support during formation. In this regard, support structures can be used to mitigate or prevent problems associated with overhangs or other structures that require support. However, traditional techniques for solving these problems require significant effort to remove support structures and / or unmelted material during post - processing, and these techniques themselves have significant drawbacks and deficiencies. Summary of the Invention

[0006] A brief overview of one or more aspects of the present invention is presented below to provide a basic understanding of these aspects. This overview is not an extensive review of all contemplated aspects and is neither intended to identify key or critical elements of all aspects nor to describe the scope of any or all aspects. Its purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description presented later.

[0007] In some aspects of the present disclosure, the techniques described herein relate to an apparatus for processing additively manufactured components and support structures, the apparatus comprising: a resonance device for resonating at least an additively manufactured component or a support structure, wherein the resonance device is configured to resonate the support structure at a frequency that causes structural failure of the support structure and separation from the additively manufactured component.

[0008] The techniques described herein further relate to an apparatus for processing an additively manufactured component, the apparatus comprising: a resonance device for resonating at least one of an additively manufactured component or an additively manufactured support structure connected to the additively manufactured component, wherein the resonance device is configured to resonate the support structure or the component at a frequency that separates unfused additive medium from the additively manufactured component.

[0009] In some additional aspects of the present disclosure, the techniques described herein relate to a method of an additively manufactured build and a support structure that mechanically supports at least a portion of the build, the method comprising: layerwise melting a powder build material to form a support structure; and layerwise melting the powder build material to form a build; wherein the support structure is formed with a failure zone adjacent to the build, wherein the failure zone is configured to structurally fail and separate from the build when subjected to resonance by a resonance device.

[0010] In additional aspects of the present disclosure, the techniques described herein relate to a non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing, the instructions executable by a processor to control an additive manufacturing device to perform: layerwise melting a powder build material to form a support structure for a build; and layerwise melting the powder build material to form a build; wherein the support structure is formed with a failure zone adjacent to the build, wherein the failure zone is configured to structurally fail and separate from the build when subjected to resonance by a resonance device.

[0011] Other aspects will become apparent to those skilled in the art from the following detailed description, in which only several exemplary embodiments are shown and described by way of illustration. As will be appreciated by those skilled in the art, the concepts described herein can have other and different embodiments, and several details can be modified in various other respects, all of which do not depart from the present disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Various features and aspects of the techniques described herein are set forth in the appended claims and drawings as follows. In the following description, throughout the specification and the drawings, like parts are respectively marked with the same reference numerals. The drawings are not necessarily drawn to scale, and in some instances, certain figures may be shown in exaggerated or generalized form for clarity and conciseness. However, when read in conjunction with the drawings, the present disclosure itself, as well as the preferred mode of use thereof, its further objects and advantages, will be better understood by reference to the following detailed description of the illustrative aspects.

[0013] Figures 1A - 1D Corresponding side views of an example powder bed fusion (PBF) system that can be used in conjunction with aspects of the present disclosure during different operating stages are shown.

[0014] Figure 2 An example of sagging deformation in a PBF system is shown.

[0015] Figure 3 An example of a support structure according to aspects of the disclosure is shown.

[0016] Figure 4 A second example of a support structure according to aspects of the disclosure is shown.

[0017] Figure 5 A third example of a support structure according to aspects of the disclosure is shown.

[0018] Figure 6A An example partial cross-sectional view of a support structure according to aspects of the present disclosure is shown.

[0019] Figure 6B An example partial cross-sectional view of a support structure at a failure zone according to aspects of the present disclosure is shown.

[0020] Figure 6C An example of a defect that can be intentionally introduced into a resonant structure according to aspects of the present disclosure is shown.

[0021] Figure 6D A schematic diagram of one of a plurality of resonant structures that can be formed at a failure zone of a support structure according to aspects of the present disclosure is shown.

[0022] Figure 7 Shows some examples of control parameters of a PBF system according to aspects of the present disclosure that can be modified to introduce defects at a failure zone while forming a support structure.

[0023] Figure 8 Shows an example resonance device according to aspects of the present disclosure.

[0024] Figure 9 Shows a second example of a resonance device according to aspects of the disclosure.

[0025] Figure 10 Shows a third example of a resonance device according to aspects of the disclosure.

[0026] Figure 11 Shows an example representative diagram of various components of an example controller that can be used with aspects of the present disclosure.

[0027] Figure 12 Shows an example of a computer system according to aspects of the present disclosure.

[0028] Figure 13 Shows examples of various system components according to aspects of the present disclosure. Detailed Description

[0029] The detailed description set forth below in connection with the accompanying drawings is intended to provide a description of various exemplary embodiments of the concepts disclosed herein and is not intended to represent the only embodiments in which the present disclosure can be practiced. The term "exemplary" as used herein means "serving as an example, instance, or illustration" and is not necessarily to be construed as preferred or advantageous over other embodiments presented in the present disclosure. The detailed description includes specific details for the purpose of providing a thorough and complete disclosure that fully conveys the scope of the concepts to those skilled in the art. However, the present disclosure may be practiced without these specific details. In some instances, well-known structures and components may be shown in block diagram form or omitted entirely in order to avoid obscuring the various concepts presented throughout the present disclosure.

[0030] Ⅰ. Terms

[0031] Throughout the specification, references to "one aspect" or "a example" mean that a particular feature, structure, or characteristic described in connection with an embodiment or example can be a feature included in at least one example of the invention. Thus, the phrases "in one aspect" and "a example" that appear in various places throughout the specification do not necessarily all refer to the same example. Additionally, a particular feature, structure, or characteristic can be combined in any suitable combination and / or sub-combination in one or more embodiments or examples.

[0032] Throughout the disclosure, the terms "substantially" or "approximately" can be used as modifiers of the geometric relationship between elements or of the shape of an element or component. While the terms "substantially" or "approximately" are not limited to a particular variation and can encompass any variation that would be understood by one of ordinary skill in the art as an acceptable level of variation, some examples are provided below. In one example, the terms "substantially" or "approximately" can include a variation of less than 10% in the dimensions of an object or component. In another example, the terms "substantially" or "approximately" can include a variation of less than 5% in the dimensions of an object or component. If the terms "substantially" or "approximately" are used to define the angular relationship between one element and another, a non-limiting example of the terms "substantially" or "approximately" can include a variation of 5 degrees or less. These examples are not intended to be limiting and can be increased or decreased based on the understanding of acceptable limits by those skilled in the relevant art.

[0033] For the purposes of the present disclosure, when an aspect or article described herein is in a use orientation, directional terms are generally expressed relative to a standard reference frame. In some examples, the directional terms are generally expressed relative to a left-handed coordinate system.

[0034] Terms such as "a" and "the" are not intended to refer only to a singular entity but also to the general category for which a particular example can be used to illustrate. The terms "a" and "the" can be used interchangeably with the term "at least one". The phrases "at least one of... " and "comprising at least one of... " following a list refer to any one of the items in the list and to any combination of two or more items in the list. Unless otherwise specified, all numerical ranges include their endpoints and non-integer values between the endpoints.

[0035] The terms "first", "second", "third", and "fourth", as well as other numerical values, may be used in this disclosure. It should be understood that these terms are used only in their relative sense, unless otherwise specified. In particular, certain components may be present in interchangeable and / or equal multiples (e.g., in pairs). For these components, in the description, the names "first", "second", "third", and / or "fourth" may be applied to the component only for convenience.

[0036] The term "powder bed fusion (PBF)" is used throughout the disclosure. A PBF system can include a variety of additive manufacturing (AM) techniques, systems, and methods. Thus, the PBF systems or processes referred to in this disclosure can include the following printing techniques: direct metal laser sintering (DMLS), electron beam melting (EBM), selective heat sintering (SHS), selective laser melting (SLM), and selective laser sintering (SLS). The PBF fusion techniques can further include, for example, solid-state sintering, liquid-phase sintering, partial melting, complete melting, chemical bonding, and other bonding and sintering techniques. Other PBF processes related to the principles of this disclosure include processes that are currently under consideration or in commercial development. Aspects of this disclosure can additionally be related to non-metallic additive manufacturing and / or metal / binder additive manufacturing (e.g., binder jetting), which can dispense with an energy beam source and instead apply a binder or other adhesive to form each layer. In the case of binder jetting, the green body or green form can be sintered or melted together in a furnace and / or infiltrated with bronze or other alloys.

[0037] The term "fusion" can be used throughout the disclosure to describe any temporary or permanent fixation or adhesion of AM powders or other known materials. In some examples, the term "fusion" can include sintering, melting, and / or adhesion of individual powder particles (e.g., via a binder or adhesive).

[0038] II. Detailed Examples

[0039] A powder bed fusion (PBF) system can produce structures (referred to as build parts) having geometrically complex shapes, including some shapes that are difficult or impossible to generate with traditional manufacturing processes. The PBF system creates the build part layer by layer (i.e., slice by slice). Each slice can be formed by a process of depositing a layer of powder (e.g., metal or metal powder) and fusing (e.g., melting and cooling) the region of the metal powder layer that corresponds to the cross-section of the build part in that slice. This process can be repeated to form the next slice of the build part, and so on.

[0040] The shapes of some build components may produce undesirable results in the finished part. For example, some shapes include overhangs, which include portions of the build component formed by melting powder on top of unfused powder. A simple example of an overhang is shown in Figure 2 which shows that a portion of the overhang region 209 may be affected by gravity, which, if not attended to, may cause the raised portion to sag or otherwise deform.

[0041] In this regard, support structures can be used to mitigate or prevent problems associated with overhang regions. Various systems, devices, and methods for forming support structures in a PBF system and for removing support structures from a build component are described herein, as well as various novel configurations of support structures. In the context of AM and associated PBF technologies, support structures can be used to counteract or otherwise mitigate the adverse consequences of overhang structures being prone to deformation or other problems. Support structures are different from (although they can be connected to) build components and, in some cases, can be fused to the build component. Some support structures can provide a mechanical connection between a support plate (also referred to as a build plate) and a build component, stabilizing structures that overhang with respect to the main structure of the build component. These types of support structures can be constructed, for example, like the build component itself, as multiple powder layers can be deposited and melted together, sintered, or otherwise cured or partially cured in an area that is typically located below and / or partially or completely surrounds the expected overhang, with each layer being sufficiently cured to provide support for the overhang to be rendered during subsequent passes of the energy beam source. Depending on the specific AM technology employed, the method for forming the mechanically connected layer can vary. Various measures can be taken to remove the support material from the build component. Particularly in the case of complex geometries, such a task may present its own set of challenges. For example, in the past, technicians had to cut the support structures, which was an additional step that reduced the efficiency of producing products using AM. As described in detail below, aspects described herein relate to devices, systems, and methods for forming support structures with a designated failure zone that is designed to fail in a controlled manner when resonated by a resonance device.

[0042] Figures 1A - 1D Corresponding side views of an example of a PBF system 100 that can be used in conjunction with aspects of the present disclosure during different operating stages are shown. As described above, Figures 1A - 1D the particular embodiment shown is one of many suitable examples of a PBF system that employs the principles of the present disclosure. It should also be noted that Figures 1A - 1DThe elements in this and other figures of the present disclosure are simplified and not necessarily drawn to scale, but are drawn larger or smaller and / or with less detail for better illustration of the concepts described herein. The PBF system 100 may include a depositor 101 that can deposit each layer of metal powder, an energy beam source 103 that can generate an energy beam, a deflector 105 that can direct or redirect the energy beam to melt the powder material, and a build plate 107 that can support one or more build parts (such as build part 109). The PBF system 100 may also include a build bottom plate 111 positioned within a powder bed receiver. The wall 112 of the powder bed receiver. The build bottom plate 111 can gradually lower the build plate 107 so that the depositor 101 can deposit the next layer. In some examples, the entire mechanism may be located within a chamber 113, which can enclose other components, thereby protecting the equipment, achieving atmosphere (e.g., providing an inert environment) and temperature regulation, and reducing the risk of contamination. The depositor 101 may include a hopper 115 and a leveler 119. The hopper contains powder 117, such as metal powder, and the leveler can level the top of each deposited layer of powder.

[0043] Specifically referring to Figure 1A , which shows the PBF system 100 after the slice of the build part 109 has been melted but before the next layer of powder is deposited. In fact, Figure 1A shows the time when the PBF system 100 has deposited and melted a partially completed build part in multiple layers to form the current state of the build part 109. The multiple deposited layers form a powder bed 121, which includes deposited but un-melted powder.

[0044] Figure 1B shows the PBF system 100 at a certain stage in which the build bottom plate 111 can reduce the powder layer thickness 123. The lowering of the build bottom plate 111 causes the build part 109 and the powder bed 121 to drop by the powder layer thickness 123, such that the top of the build part and the powder bed is lower than the top of the powder bed receiver wall 112 by an amount equal to the powder layer thickness. In this way, for example, a space with a constant thickness equal to the powder layer thickness 123 can be formed above the top of the build part 109 and the powder bed 121.

[0045] Figure 1C shows the PBF system 100 at a certain stage in which the depositor 101 is positioned to deposit the powder 117 into the space formed above the top surface of the build part 109 and the powder bed 121 and bounded by the powder bed receiver wall 112. In this example, the depositor 101 moves above the defined space while releasing the powder 117 from the hopper 115. The leveler 119 can level the released powder to form a powder layer 125 that has a thickness equal to the powder layer thickness 123 (see Figure 1B) Substantially equal thicknesses. Thus, the powder in a PBF system can be supported by a powder material support structure, which can include, for example, build plate 107, build base plate 111, build member 109, walls 112, etc. It should be noted that the shown thickness of powder layer 125 (i.e., powder layer thickness 123( Figure 1B )) is greater than the actual thickness used in the example involving 150 previously deposited layers discussed above with reference to Figure 1A .

[0046] Figure 1D FIG. shows PBF system 100 at a stage in which, after depositing powder layer 125( Figure 1C ), energy beam source 103 generates energy beam 127, and deflector 105 applies the energy beam to melt, sinter, and / or fuse the next slice in build member 109. In various exemplary embodiments, energy beam source 103 can be an electron beam source, in which case energy beam 127 constitutes an electron beam. Deflector 105 can include deflection plates that can generate an electric or magnetic field that selectively deflects the electron beam such that the electron beam scans the area designated to be melted. In various embodiments, energy beam source 103 can be a laser, in which case energy beam 127 is a laser beam. Deflector 105 can include an optical system that uses reflection and / or refraction to manipulate the laser beam to scan the selected area to be melted. In various embodiments, deflector 105 can include one or more gimbals and actuators that can rotate and / or translate energy beam source to position the energy beam. In various embodiments, energy beam source 103 and / or deflector 105 can modulate the energy beam, e.g., turn the energy beam on and off as the deflector scans, such that the energy beam is applied only to the appropriate blocks of the powder layer. For example, in various aspects of the present disclosure, the energy beam can be modulated by a digital signal processor (DSP). The deflector can include any known system in the art, such as a galvo-scanner or galvanometer and / or raster scanner. It should be noted that while a single energy beam source 103 and / or deflector 105 is shown, aspects of the present disclosure can be used with and can include systems having multiple energy sources and / or deflectors.

[0047] As Figure 1D shown, most of the melting of powder layer 125 occurs in the area located on top of the previous slice of the powder layer (i.e., the previously melted powder). An example of such an area is the surface of build member 109. Figure 1DThe melting of the powder layer occurs above the previously melted layer that characterizes the solid of the build 109. However, in some regions of the powder layer 125, melting may occur inadvertently or otherwise on top of the loose powder (i.e., above the unmelted powder). For example, if the slice area is larger than the previous slice area, at least some of the slice area will form above the loose powder. Applying an energy beam to melt the powder region above the loose powder can be problematic. The melted powder is liquefied and is generally denser than the loose powder. The melted powder may percolate into the loose powder, causing the build 109 to sag, curl, or otherwise deform undesirably. Because the loose powder may have low thermal conductivity, when melting the powder in the overhanging region, a higher temperature than expected may result because the low thermal conductivity can reduce the ability of thermal energy to conduct away from the melted powder during melting. The higher temperature in these regions can result in higher residual stresses after cooling and generally lead to a poor-quality build. In some cases, these residual stresses can cause a portion of the build to curl upward, which may protrude from the powder bed and collide with the depositor when the next layer of material is deposited. In some cases, scum may form in the overhanging region, resulting in an undesirable surface roughness or other quality issues.

[0048] Figure 2 A side view showing an example of sagging or drooping deformation in a PBF system that can result in unsupported overhanging regions. Figure 2 The build plate 201 and the powder bed 203 are shown. In the powder bed 203 is an example of the actual build 205. For comparison purposes, the model build 207 is shown by a dashed line. In one embodiment, the model build 207 includes data from a data model created in CAD to be used as input to an AM processor to render the build. The model build 207 shows the desired shape of the build. The actual build 205 overlaps the model build 207 at most locations (i.e., at locations without deformation). Thus, in the region to the right of the overhang boundary 210, the solid line that characterizes the actual build 205 overlaps the dashed line defined in the model build 207. However, sagging deformation occurs in the overhanging region 209. In this example, the overhanging region 209 is formed by a plurality of slices melted on top of each other. In this case, the deformation worsens as the overhanging region 209 extends from the body of the actual build 205. As Figure 2 shown by the actual build 205 in

[0049] It should be noted that some problems (such as warping, high residual stress, etc.) may occur in the following regions, where the powder in one layer melts near the edge of the slice in the next layer (even if the melting does not occur directly above the loose powder). For example, when melting the powder near the edge of the underlying slice, it may lead to unexpected high temperatures because there is less molten material below to conduct away the heat. These problems may be particularly severe when the underlying slice forms a sharp edge. In this regard, support structures can be used to mitigate or prevent the deformation and other problems that may also occur in these regions near the overhang area. As used herein, terms such as "overhang area" are intended to include the areas near the overhang area and above the molten powder, such as the area adjacent to where the powder melts near the edge of the underlying slice as described above, the areas where the slice forms a sharp corner or edge, and similar areas that may result in the above-described array of undesirable overhang machining artifacts in the target build.

[0050] Figures 3 - 5 An example system, method, and configuration for a support structure are shown, where the particles of loose powder can melt or otherwise bond to the build in areas where a support is needed to control the above effects. Figures 6A - 10 Relates to a method for removing a support structure according to aspects of the present disclosure.

[0051] Figure 3 Is a side view of an example of a molten powder support structure 300. Figure 3 The build plate 301 and the powder bed 303 are shown. In the powder bed 303, there is a build 305 that includes an overhang area 307. In the powder bed 303, below the portion of the build 305 that is located in the overhang area 307, there is an area of molten powder 309. As described above, the molten powder can include melted powder, bonded powder, compacted powder, partially sintered powder, powder coated with a binder, etc. The molten powder 309 can form a support structure 300 that supports the portion of the build 305 that is located in the overhang area 307. In this way, for example, the support structure 300 formed by the molten powder 309 mitigates or prevents the deformation and other undesirable machining defects of the build 305. As Figure 3 shown, an example of a support structure can include a grid structure that includes molten powder and loose powder.

[0052] Figures 4 - 5 Corresponding side views of additional examples of builds and support structures that can be formed using a PBF device are shown. Figure 5A side view showing another example configuration of a support structure 400 located in a overhang region 407 of a powder bed 403 is shown. The build can be partially supported by a build plate 401. The powder bed 403 can also be supported by the build plate 401. The build 405 can include an overhang region 407 or other portions that require support to maintain an acceptable quality of the build 405. In this example, the support structure 400 can be formed by a region of molten powder 409 that is connected to the build 405. In this example configuration, the support structure 600 does not extend down to the build plate 401. Thus, the support structure 400 and the overhang region 407 are only supported by loose or compacted powder. However, the support structure 400 can support the build 605 because the support structure can "float" on the loose powder in the powder bed 603. More specifically, the molten powder 409 can be formed to increase the surface area of the molten powder that contacts the loose or compacted powder, such that the deformation forces acting on the build 405 can be distributed over a larger area of loose or compacted powder. In this way, the forces can be distributed in such a manner that the loose powder located beneath the support structure 400 can provide a sufficient non-deformable connection between the support structure 400 and the build plate 401. Thus, even though the support structure does not extend all the way to the build plate 401, the support structure 400 can effectively support the portion of the build 405 that is located in the overhang region 407. For example, in Figure 4 the configuration, a region of molten powder 411 is located above a region of molten powder 413, and the molten powder 413 is located above a region of non-molten powder 415. The foregoing type of support structure allows for the use of less powder to form the support structure, which, among other benefits, reduces build time and allows more powder to be recycled and reused. These factors together result in cost savings, manufacturing efficiency, and potential time-to-market advantages.

[0053] Additionally, the foregoing support structure can allow for more efficient construction of additional builds during a single PBF AM run. For example, additional builds can be constructed in the space of the loose powder located beneath an anchored support structure (i.e., in the space where other support structures would typically extend through to reach the build plate downward). In another example, a molten powder region 409 having a relatively large area 413, a second adjacent component (not shown) can be configured to use opposite sides of the molten powder region 409 adjacent to the build 405 as a support structure for overhang support. These examples potentially allow for a greater ability to render more types of builds in a relatively short period of time.

[0054] Figure 5 is a side view of another example of a molten powder support structure 500. Figure 5 A build plate 501 and a powder bed 503 are shown. In the powder bed 503, there is a build 505, which can be associated withFigures 1A - 1D the building member 109 in Figure 2 the building member 205 in Figure 3 the building member 305 in and / or Figure 4 the building member 409 in are similar and / or share similarities. The building member 505 may include a overhang region 307 and / or other portions that may require support. In the powder bed 503, below the portion of the building member 505 that is located in the overhang region 507, there is a region of molten powder 509 for supporting the overhang region 507. As described above, the molten powder may be, for example, melted or sintered powder, partially sintered powder, and / or powder coated with a binder. The molten powder 509 may form a support structure 500 that supports the portion of the building member 505 that is located in the overhang region 507. In this way, for example, the support structure 500 formed by the molten powder 509 alleviates or prevents the building member 505. An example of a support structure may include a single or multiple branch structures or a series of support members that are vertically and / or substantially vertically oriented, which include molten powder and loose powder.

[0055] As Figures 3 - 5 further shown in the example of Figure 3 the build plate 301 in and / or Figure 5 the build plate 519 in

[0056] The failure zones of the support structure (e.g., 300, 400, 500) (e.g., Figure 3 317 and / or 319 in Figure 4 417 and / or in Figure 5517 and / or 519) in may include any one or combination of structures that form (e.g., by fusing powder using the methods and apparatuses described above) a deliberately formed defect in a structure having a resonant geometry and / or support structure at or near the failure zone. In some aspects of the present disclosure, a tuned geometry may be formed to additionally improve the removal of excess loose powder from the build. The support structure may have a resonant support structure that is formed such that vibration of the resonant support structure at its natural frequency causes the support structure to disengage from the build and / or build plate. This may be due to, for example, metal fatigue at the interface between the support structure and the build and / or build plate.

[0057] Accordingly, by implementing the features and methods described herein, post-processing steps (e.g., powder removal, support removal, and / or build removal) may be simplified and / or fully or partially automated, resulting in improved efficiency and cost. In some examples, the build and any necessary support structures may be formed using a PBF apparatus as described above, and once the build and necessary supports are complete, both the supports and the unfused powder may be removed by a resonance apparatus that may be integrated with or otherwise associated with the PBF apparatus.

[0058] In other aspects, the build and supports (and any unfused powder) may be removed from the PBF apparatus and placed in, connected to, or contacted by a resonance apparatus. The resonance apparatus may apply one or more resonance frequencies such that the connection between the support structure and the build mechanically fails at the failure zone. Resonance may additionally remove or separate the unfused powder from the build.

[0059] Figure 6A is an example partial cross-sectional view of a support structure 617a. The support structure 617a may include a section of unfused powder 651a between sections of fused powder 655b. Figure 6B is at the failure zone (e.g., Figure 3 the failure zone 317 and / or 319 in Figure 4 417 in Figure 5 517 and / or 519) in. An example partial cross-sectional view of a support structure 617b at the failure zone. The support structure 617b at the failure zone includes or may be formed to include a fused powder in the form of a resonant structure 655b. The resonant structure 655b may be elongate and / or may otherwise include a geometry that resonates (i.e., in the RR direction) when subjected to a resonant force.

[0060] Figure 6D is a schematic diagram of one of a plurality of resonant structures that may be formed at the failure zone 617b of a support structure. As Figure 6DAs shown, when the resonance structure 655b is subjected to a bending frequency resonance force, the resonance structure 655b can oscillate as shown by the dashed line in Figure 6D .

[0061] In one example, the bending frequency f of the resonance structure 655b n can be calculated using the following equation (F).

[0062]

[0063] In the above equation (F), the variable E is the modulus of elasticity, I is the moment of inertia, L is the length, ρ is the mass density (mass / length), and P is the applied force. More specifically, the natural resonance bending frequency and / or any one or combination of the length, mass density, and / or modulus of elasticity of the resonance structure 655b can be calculated using equations (F-1) to (F-61) in the equation table submitted here. The entire content of the above equation table is incorporated herein by reference.

[0064] In some examples, the bending resonance frequency of the resonance structure 655b can range from 50 Hertz (Hz) to 1000 Hz. In another example, the resonance frequency of the resonance structure 655b can be 100 Hz - 900 Hz. In yet another example, the resonance frequency of the resonance structure 655b can be 200 Hz - 900 Hz.

[0065] In some examples, the building member and / or support structure can be subjected to the low frequency of the resonance structure 655b (e.g., the frequency for maximum deflection as shown in FIG. 6 above), and can additionally be subjected to a second higher frequency to induce high cycle fatigue stress. The range of the aforementioned high frequency can be from 900 Hz - 2000 Hz. In another example, the range of the frequency can be from 950 Hz - 1950 Hz. In yet another example, the frequency range can be 1100 Hz - 1900 Hz. Combining the high frequency with the low frequency (e.g., when applying resonance via the resonance device described in further detail below) can improve the efficiency of separating the support structure from the building member and / or building plate. For example, applying the high frequency and the low frequency to the building member and / or support structure simultaneously can reduce the time required to separate the aforementioned structures.

[0066] It should be noted that although an elongated resonance structure is shown in Figure 6D , any known resonance structure can be formed into the support structure (e.g., a beam with a central mass, a cantilever with or without end masses). Additionally, the resonance structure 655b can be geometrically tapered or otherwise thinned at or near the desired fracture zone or area. Additional non-limiting examples are provided in the equation table and throughout the disclosure mentioned above.

[0067] In some examples, the resonant structure 655b can be a half-wave resonator configured to oscillate or otherwise resonate when a resonant frequency is applied thereto. As Figure 6D shown in the example of Figure 3 , applying a resonant force at a resonant frequency or frequency range causes the resonant structure 655b to resonate (e.g., in the direction RR). The resonance of the resonant structure 655b can result in a specified or predetermined failure zone (e.g., Figure 4 the failure zones 317 and / or 319 in Figure 5 , the failure zone 417 in

[0068] or the failure zones 517 and / or 519 in

[0069] ) in the support structure 617b, causing controlled failure of the resonant structure 655b in the support structure, such that the support structure is completely or partially separated from the build part and / or build plate, which eliminates or simplifies the step of removing the support structure from the build part during post-processing of a PBF or AM build.

[0070] In some embodiments, resonance can also be used to remove unfused powder from the support structure and / or build part. For example, when the resonant structure 655b resonates, any unfused powder can be vibrated out of the build part and / or support structure. Combining the separation of the support structure and the removal of unfused powder further improves the efficiency of post-processing.

[0069] Just as the resonant structure 655b can be formed to resonate at a specific frequency or frequency range to provide controlled failure of the support material in the failure zone of the support structure, the resonant structure can additionally be formed to resonate at a frequency that helps remove unfused powder. For example, the resonant structure 655b can be formed to resonate at a frequency of 900 Hz - 2000 Hz. In another example, the frequency range can be from 950 Hz - 1950 Hz. In yet another example, the frequency range can be 1100 Hz - 1900 Hz.

[0070] In some example embodiments, during a PBF or AM build process, defects can be intentionally introduced into the support structure to facilitate separation of the support structure from the build part and / or build plate or even other support structures. Figure 6C Figure 6D shows an example of a defect 659 introduced into the resonant structure 655b. When the resonant structure 655b deflects, the defect 659 introduced into the support structure 617b weakens the molten support structure and allows cracks 657 in the support structure 617b to propagate. In other words, the reduced material fracture toughness due to the defect 659 allows the support structure to undergo controlled failure and separation when subjected to deflection (e.g., as shown in

[0071] ) caused by the resonance of the resonant structure 655b. Figure 6C In the example shown inFigure 3 in the failure zones 317 and / or 319, Figure 4 in the failure zone 417 or Figure 5 in the resonance structure 655b at the failure zone 517 and / or 519). In one example, the defect 659 may be created by controlling the PBF system to introduce porosity and / or lack of melting in the support structure located at or near the desired failure zone.

[0072] Figure 7 Some examples of control parameters of the PBF system are shown, which can be modified to introduce the defect 659 while forming the support structure. Figure 7 In the chart of, the X-axis represents the volume energy density (VED) of the PBF system during the formation of the build and / or the support structure. The Y-axis represents the percentage of porosity in the molten material. Generally, when forming a build, the goal is to minimize porosity to improve the structural properties of the build. As Figure 7 shown, the line 761 represents an example of the VED value that results in the minimum porosity of the build as shown in the cross-section 759b. Increasing or decreasing the VED beyond the optimal range results in porosity and thus a reduction in the strength of the build, either due to lack of melting (e.g., as shown in the cross-section 759a) or due to porosity caused by gas pores and / or holes (e.g., as shown in the cross-section 759c).

[0073] The VED can be a parameter of the energy beam source 103 ( Figures 1A - 1D ), and / or the deflector 105 and / or the powder layer thickness provided by the depositor 101. In one example, the VED in joules per millimeter 3 (J / mm 3 ) is defined by the following equation G, where E is the power of the energy source for melting the powder build material, S is the scanning speed of the energy source, L is the thickness of the unmelted powder build material, and H is the hatch spacing of the energy source for melting the powder build material.

[0074]

[0075] As Figure 7 shown, a VED of 30 J / mm 3 - 40 J / mm 3 reduces the defects that occur during powder melting during the build process. When the VED is increased to above 40 J / mm 3 or reduced to below 30 J / mm 3 , defects such as lack of melting, gas pores, and / or holes may occur in the molten material. Therefore, by increasing or decreasing the VED, defects (e.g., Figure 6CThe defect 659) in is introduced into the support structure at the desired failure zone (e.g., Figure 3 the failure zones 317 and / or 319 in, Figure 4 the failure zone 417 in, or Figure 5 the failure zones 517 and / or 519 in).

[0076] In an example embodiment of the present disclosure, the PBF system can be controlled such that the VED at the failure zone and / or at the resonant structure (e.g., Figure 6B and Figure 6D the resonant structure 655b in) can be 40 J / mm 3 -80 J / mm 3 . In another example, the VED can be 45 J / mm 3 -80 J / mm 3 . In yet another example, the VED can be 55 J / mm 3 -80 J / mm 3 .

[0077] In another example embodiment, the PBF system can be controlled such that the VED at the failure zone and / or at the resonant structure (e.g., Figure 6B and Figure 6D the resonant structure 655b in) can be 1 J / mm 3 -35 J / mm 3 . In another example, the VED can be 20 J / mm 3 -35 J / mm 3 . In yet another example, the VED can be 20 J / mm 3 -30 J / mm 3 . By increasing the VED as described above, the defect of lack of melting can be introduced into the support structure to allow for controlled failure at the failure zone as described above.

[0078] In some example embodiments of the present disclosure, the PBF system can be controlled such that the VED when forming the layer of the build (i.e., the support structure) at the failure zone is 20%-40% higher than the VED when forming the layer of the build part. Similarly, the VED at the failure zone may also be lower than the optimal value for forming the build part. For example, the VED when forming the layer of the build (i.e., the resonant structure of the support structure) at the failure zone can be 20%-40% lower than the VED when forming the layer of the build part.

[0079] Figures 8 - 10 Shows an example of a vibration or resonance feature that can be used in conjunction with the above aspects to form a support structure (e.g., Figure 3 the support structure 300 in, Figure 4 the support structure 400 in,Figure 5 the support structure 500 in and / or Figures 6A - 6B the support structures 617a and 617b in) from a building member (e.g., Figures 1A - 1D the building member 109 in Figure 3 the building member 305 in Figure 4 the building member 405 in Figure 5 the building member 505 in) and / or a building plate ( Figures 1A - 1D the building plate 107 in Figure 3 the building plate 301 in, the building plate 401 in FIG. 1 and / or Figure 5 the building plate 501 in) are removed, and / or unmelted powder (e.g., Figures 1A - 1D the powder in the powder bed 121 in Figure 2 the powder in the powder bed 203 in Figure 3 the powder in the powder bed 303 in Figure 4 the powder in the powder bed 403 in Figure 5 the powder in the powder bed 503 in and / or Figures 6A - 6D the unmelted powder 651a and / or 651b in) is separated from the building member and / or the support structure. The examples described below can be integrated into a PBF system (e.g., Figures 1A - 1D the PBF system 100 in) to allow for post - forming separation of the support structure, the building plate, and / or the loose powder at the same PBF system where the building member is formed. In another example, the vibration or resonance feature can be a separate resonance processing device into which or onto which a user can place the building member for post - processing. In another example, an automated system (such as a robot or a conveyor) can transfer the building member to a resonance processing system.

[0080] Figure 8 An example device 800 is shown for resonating at least one of a building member 805 and / or an additive - manufactured support structure 809 connected to the building member. In Figure 8 the example of, the device can have a container 860 configured to hold a liquid 820 (e.g., water, deionized water, and / or a cleaning agent). The device 800 can have one or more oscillators / transducers 801 that oscillate when an electric current is provided to the transducer 801. The electric current can be provided at one or more controlled frequencies via an ultrasonic generator 803. The oscillator / transducer 801 can be configured to induce a propagating wave and / or cavitation in the liquid 820. The propagating wave in the liquid 820 causes the support structure and / or the loose powder to resonate, and due to material failure at the failure zone 817 as described above, the separation or partial separation of the support structure 809 from the building member 805 occurs.

[0081] In some examples, the transducer 801 can be controlled to generate a signal at a failure zone 817 (eg, Figure 3 The failure areas 317 and / or 319 in Figure 4 Failure area 417 or Figure 5 The failure regions 517 and / or 519 in the embodiment are provided with a resonant structure (e.g., Figures 6B - 6D The ultrasonic generator 803 can be controlled to induce a resonant wave in the liquid 820 at a resonant frequency and / or a semi-resonant frequency of the resonant structure 655b in the liquid 820. In some examples, the ultrasonic generator 803 can be controlled to induce a vibration of 50 Hertz (Hz) to 1000 Hz to the liquid 820. In another example, the ultrasonic generator 803 can induce a vibration of 100 Hz-900 Hz. In another example, it is 200 Hz-900 Hz. In some examples, the ultrasonic generator can induce a higher frequency vibration at the same time and / or before and / or after the above frequencies. Some examples of higher frequency vibrations can be 900 Hz-2000 Hz, 950 Hz-1950 Hz and / or 1100 Hz-1900 Hz. Combining high frequency with low frequency can improve the efficiency of separating the support structure 809 from the building piece 805 and / or the building plate. For example, applying high frequency and low frequency to the building piece and / or the support structure at the same time can reduce the time required to separate the aforementioned structures. In some examples, after build 109 is completed and / or at specified times during construction, a message may be sent to PBF system 100 ( Figures 1A - 1D ) supply liquid 820. Before providing liquid 860, unmelted powder in powder bed 121 may be removed.

[0082] Figure 9 and Figure 10 Other examples of resonance devices and vibration or resonance features that may be used with the above aspects are shown. Figure 9 An example system and method is shown that includes a resonant device 900 having a resonator and / or vibrator 990 that can apply a resonant frequency to remove support structures 909 and / or unmelted powder. The vibrator 990 can cause mechanical excitation via any one or combination of, for example, an ultrasonic transducer, a piezoelectric transducer, a micro-electromechanical system, to name a few non-limiting examples. Figure 9 Build plate 901 and build piece 905 are shown. It should be noted that although support structure 809 is indicated as a vertically extending support structure, the features described are applicable to any type of support structure. For example, a resonator can be used to remove Figure 3 The supporting structure 300, Figure 4 The supporting structure 400, Figure 5 The support structure 500 and / or Figures 6A - 6B Any one or combination of support structures 617a and 617b.

[0083] The resonator / vibrator 990 can be coupled to the base member 905 such that a resonant frequency can be applied to cause the support structure 909 to vibrate or resonate. In some examples, the resonator / vibrator 990 can apply resonance at the resonant frequency or half-resonant frequency of a resonant structure (e.g., the resonant structure 655b in Figures 6B - 6D ). The resonance can cause the molten support to fail at the designated failure zone 917 and thus separate. The designated failure zone can be similar to or analogous to, for example, the failure zones 317 and / or 319 in Figure 3 and / or the failure zone 417 in Figure 4 or the failure zones 517 and / or 519 in Figure 5 . The vibrator 990 can be controlled to initiate vibrations from 50 Hertz (Hz) to 1000 Hz. In another example, the vibrator 990 can initiate vibrations of 100 Hz - 900 Hz. In yet another example, it is 200 Hz - 900 Hz. In some examples, the vibrator 990 can initiate higher frequency vibrations simultaneously with and / or before and / or after the above frequencies. Some examples of higher frequency vibrations can be 900 Hz - 2000 Hz, 950 Hz - 1950 Hz, and / or 1100 Hz - 1900 Hz. Combining high frequencies with low frequencies can improve the efficiency of separating the support structure 909 from the member 905 and / or the build plate 901. In various aspects, the vibrator 990 can initiate a first frequency that is tuned to cause vibrations of the support structure that are more effective in removing unfused powder, the first frequency being, for example, a relatively low frequency to cause a greater deflection of the resonant structure of the support structure (e.g., the resonant structure 655b). In various embodiments, after the unfused powder is removed, the vibrator 990 can initiate a second frequency that is tuned to cause vibrations of the support structure that are more effective in causing fatigue and damaging the support structure, the second frequency being, for example, a relatively high frequency to cause a higher rate of back-and-forth deflection of the resonant structure to initiate high cycle fatigue stress. In some examples, the above two frequencies can be applied simultaneously and / or partially overlap for separating and removing unfused powder.

[0084] In Figure 9 the example shown, resonance can be applied via mechanical conduction directly or indirectly through the member. Although Figure 9 shows the vibrator 990 connected to or in contact with the member 905, the vibrator 990 can be connected to or indirectly connected to any one or combination of the support structure, build plate, etc.

[0085] Figure 10An example system and method are shown that include a resonance device 1090 having a resonator and / or vibrator 990 that can apply a resonance frequency to a support structure 1009 for removing the support structure 1009 and / or unfused powder. The vibrator 1090 can cause mechanical excitation via any one or combination of, for example, an ultrasonic transducer, a piezoelectric transducer, a microelectromechanical system (to name just a few non-limiting examples).

[0086] Figure 10 A build plate 1001 and a build 1005 are shown. It should be noted that while the support structure 1009 is depicted as a grid-type support structure, the described features can be applicable to any type of support structure. For example, a resonator can be used to remove Figure 3 the support structure 300 in Figure 4 the support structure 400 in Figure 5 the support structure 500 and / or Figures 6A - 6B any one or combination of the support structures 617a and 617b in

[0087] The resonator / vibrator 1009 can be coupled to and / or can be configured to contact the support structure 1009 such that a resonance frequency can be applied to cause the support structure 1009 to vibrate or resonate. In some examples, the resonator / vibrator 1009 can apply resonance at the resonance frequency or half-resonance frequency of a resonance structure (e.g., Figures 6B - 6D the resonance structure 655b in Figure 3 the failure zones 317 and / or 319 in Figure 4 the failure zone 417 in Figure 5The failure zones 517 and / or 519 therein share similarities or can be similar thereto. The vibrator 990 can be controlled to induce vibrations from 50 Hertz (Hz) to 1000 Hz. In another example, the vibrator 1090 can induce vibrations of 100 Hz - 900 Hz. In yet another example, it is 200 Hz - 900 Hz. In some examples, the vibrator 1090 can induce higher frequency vibrations simultaneously with and / or before and / or after the above frequencies. Some examples of higher frequency vibrations can be 900 Hz - 2000 Hz, 950 Hz - 1950 Hz, and / or 1100 Hz - 1900 Hz. Combining high frequencies with low frequencies can improve the efficiency of separating the support structure 1009 from the build member 1005 and / or the build plate 1001. In various embodiments, the vibrator 990 can induce a first frequency that is tuned to cause vibrations of the support structure that are more effective in removing unfused powder. The first frequency is, for example, a relatively low frequency to cause a greater deflection of the resonant structure (e.g., resonant structure 655b) of the support structure. In various embodiments, after the unfused powder is removed, the vibrator 990 can induce a second frequency that is tuned to cause vibrations of the support structure that are more effective in causing fatigue and breaking the support structure. The second frequency is, for example, a relatively high frequency to cause a higher back-and-forth deflection rate of the resonant structure to induce high cycle fatigue stress.

[0088] In Figure 10 the example shown, resonance can be applied via mechanical conduction directly or indirectly through the support structure 1009. Although Figure 10 the vibrator 1090 connected to or in contact with the support structure 1009 is shown, the vibrator 1090 can be connected to or indirectly connected to any one or combination of the support structure, the build plate, etc. For example, in one aspect, the vibrator 990 described above with respect to Figure 9 can be implemented into Figure 10 the resonance device 1000 such that both the support structure 1009 and the build member 1005 can be mechanically excited to further improve the separation efficiency of the support structure and / or any unfused powder.

[0089] It should be noted that the above operations are provided as examples. Although some specific examples are given, those of ordinary skill in the art will understand that after understanding the disclosure provided herein, other possibilities of automatically controlling, semi-automatically controlling, or manually controlling the systems and devices of the methods and apparatuses for forming and removing the disclosed support systems will fall within the scope of this disclosure.

[0090] In some embodiments, as part of or in combination with the various features and methods described herein, one or more microcontrollers may be implemented to control any one or combination of the operations described herein (e.g., the operations of the PBF system and / or support removal system and devices described herein). Various components of an example of such a controller 1100 are shown in Figure 11 in a representative block diagram form. In Figure 11 , the controller 1100 includes a CPU 1102, a clock 1104, a RAM 1108, a ROM 1110, a timer 1112, a bus controller 1114, an interface 1116, and an analog-to-digital converter (ADC) 1118 interconnected via a bus 1106. The CPU 1102 may be implemented as one or more single-core or multi-core processors and receives signals from an interrupt controller 1120 and the clock 1104. The clock 1104 may set the operating frequency of the entire microcontroller 1100 and may include one or more crystal oscillators having a predetermined frequency. Alternatively, the clock 1104 may receive an external clock signal. The interrupt controller 1120 may also send an interrupt signal to the CPU to pause CPU operation. When an event requires immediate CPU attention, the interrupt controller 1120 may pass an interrupt signal to the CPU.

[0091] The RAM 1108 may include one or more static random access memories (SRAM), dynamic random access memories (DRAM), synchronous dynamic random access memories (SDRAM), double data rate random access memories (DDR SDRAM), or other suitable volatile memories. The read-only memory (ROM) 1110 may include one or more programmable read-only memories (PROM), erasable programmable read-only memories (EPROM), electrically erasable programmable read-only memories (EEPROM), flash memories, or other types of non-volatile memories.

[0092] The timer 1112 may record time and / or calculate the amount of time between events occurring within the controller 1100, count the number of events, and / or generate a baud rate for communication transmission. The bus controller 1114 may prioritize bus usage within the controller 1100. The ADC 1118 may allow the controller 1100 to issue pulses to send signals to other devices.

[0093] The interface 1116 may include input / output devices that allow the controller 1100 to exchange information with other devices. In some embodiments, the interface 1116 may include one or more of a parallel port, a serial port, or other computer interfaces.

[0094] In addition, aspects of the present disclosure can be implemented using hardware, software, or a combination, and can be implemented in one or more computer systems or other processing systems. In one aspect of the present disclosure, a feature refers to one or more computer systems capable of performing the functions described herein. An example of such a computer system 2000 is shown in Figure 12 as follows.

[0095] The computer system 2000 can include one or more processors, such as processor 2004. The processor 2004 can be connected to a communication infrastructure 2006 (e.g., a communication bus, a cross-over bar, or a network). Various software aspects are described in accordance with this example computer system. After reading this specification, those skilled in the relevant art will understand how to implement aspects of the present disclosure using other computer systems and / or architectures.

[0096] The computer system 2000 can include a display interface 2002 that forwards graphics, text, and other data from the communication infrastructure 2006 (or from a frame buffer not shown) for display on a display unit 2030, which can be similar to the display interface 102. The computer system 2000 also includes a main memory 2008, which is preferably a random access memory (RAM), and the computer system can also include an auxiliary memory 2010. The auxiliary memory 2010 can include, for example, a hard disk drive 2012 and / or a removable storage drive 2014, representing a floppy disk drive, a tape drive, an optical disk drive, a universal serial bus (USB) flash drive, etc. The removable storage drive 2014 reads from and / or writes to a removable storage unit 2018 in a well-known manner. The removable storage unit 2018 represents a floppy disk, a tape, an optical disk, a USB flash drive, etc., and the removable storage unit is read from and written to by the removable storage drive 2014. As will be appreciated, the removable storage unit 2018 includes a computer-usable storage medium having computer software and / or data stored therein.

[0097] Alternative aspects of the present disclosure may include secondary storage 2010 and may include other similar devices for allowing a computer program or other instructions to be loaded into computer system 2000. Such devices may include, for example, removable storage unit 2022 and interface 2020. Such examples may include a program cartridge and a cartridge interface (such as found in video game devices), a removable memory chip (such as an erasable programmable read only memory (EPROM) or programmable read only memory (PROM)) and associated socket, and other removable storage unit 2022 and interface 2020 that allows software and data to be transferred from the removable storage unit 2022 to computer system 2000.

[0098] Computer system 2000 may also include communication interface 2024. Communication interface 2024 allows software and data to be transferred between computer system 2000 and external devices. Examples of communication interface 2024 may include a modem, a network interface (such as an Ethernet card), a communication port, a Personal Computer Memory Card International Association (PCMCIA) slot and card, etc. The software and data transferred via communication interface 2024 are in the form of signals 2028, which may be electrical signals, electromagnetic signals, optical signals, or other signals that can be received by communication interface 2024. These signals 2028 are provided to communication interface 2024 via a communication path (e.g., a channel) 2026. This path 2026 carries signals 2028 and may be implemented using wires or cables, optical fibers, telephone lines, cellular links, RF links, and / or other communication channels. In this document, the terms "computer program medium" and "computer usable medium" are used to generally refer to media such as removable storage drive 2018, a hard disk installed in hard disk drive 2012, and signals 2028. These computer program products provide software to computer system 2000. Aspects of the present disclosure relate to such computer program products.

[0099] A computer program (also referred to as computer control logic) is stored in main memory 2008 and / or secondary storage 2010. The computer program may also be received via communication interface 2024. Such a computer program, when executed, causes computer system 2000 to perform the features in accordance with aspects of the present disclosure as discussed herein. In particular, the computer program, when executed, causes processor 2004 to perform the features in accordance with aspects of the present disclosure. Thus, such a computer program represents the controller of computer system 2000.

[0100] In one aspect of the present disclosure, in which the method is implemented using software, the software may be stored in a computer program product and loaded into the computer system 2000 using a removable storage drive 2014, a hard disk drive 2012, or a communication interface 2020. The control logic (software), when executed by the processor 2004, causes the processor 2004 to perform the functions described herein. In some examples, the computer system 2000 may include: one or more PBF controllers 1904, such as for controlling any one or combination of the PBF systems described above with reference to Figures 1A - 7 any one or combination of those described; and / or any one or combination of resonance controllers 1905, which may, for example, control any one or combination of the features described above with reference to Figures 8 - 10 any one or combination of those described. In another aspect of the present disclosure, the system is implemented primarily in hardware using, for example, hardware components such as application specific integrated circuits (ASICs). It will be apparent to those skilled in the relevant art how to implement a hardware state machine to perform the functions described herein.

[0101] Figure 13 is a block diagram of various example communication system components available in one aspect of the present disclosure. The communication system 2100 includes one or more accessors 2160, 2162 (which may, for example, include any one of the foregoing systems and features) and one or more terminals 2142, 2166. In one aspect, data used in accordance with aspects of the present disclosure is input and / or accessed, for example, via terminals 2142, 2166 (such as a personal computer (PC), minicomputer, mainframe computer, microcomputer, telephone device, or wireless device (such as a personal digital assistant (“PDA”)) or a handheld wireless device (such as a PC, minicomputer, mainframe computer, microcomputer) coupled to a server 2143 or other device having a processor and a data repository and / or coupled to a data repository via, for example, a network 2144 (such as the Internet or an intranet) and couplers 2145, 2146, 2164. The couplers 2145, 2146, 2164 include, for example, wired links, wireless links, or fiber optic links. In another example variant, the methods and systems in accordance with aspects of the present disclosure operate in a stand-alone environment, such as operating on a single end.

[0102] Additional aspects of the present disclosure are described in the following clauses:

[0103] Clause 1. An apparatus for processing an additively manufactured part and a support structure, the apparatus comprising: a resonance device for causing at least the additively manufactured part or the support structure to resonate, wherein the resonance device is configured to cause the support structure to resonate at a frequency that causes structural failure of the support structure and separation from the additively manufactured part.

[0104] Clause 2. The apparatus according to Clause 1, wherein the resonance apparatus is a transducer.

[0105] Clause 3. The apparatus according to any one of the preceding clauses, wherein the transducer is configured to oscillate when current is supplied to the transducer via an ultrasonic generator, and wherein the transducer oscillates the additively manufactured part or support structure at the frequency.

[0106] Clause 4. The apparatus according to any one of the preceding clauses, wherein the transducer is configured to at least contact the additively manufactured part or support structure.

[0107] Clause 5. The apparatus according to any one of the preceding clauses, wherein the frequency is 1100 - 1900 Hertz (Hz).

[0108] Clause 6. The apparatus according to any one of the preceding clauses, further configured to resonate the additively manufactured part or support structure at a second resonance frequency that separates unfused additive medium from the additively manufactured part.

[0109] Clause 7. The apparatus according to any one of the preceding clauses, wherein the second resonance frequency is 200Hz - 900Hz.

[0110] Clause 8. The apparatus according to any one of the preceding clauses, further comprising: a liquid container configured to contain liquid and the additively manufactured part and support structure; a transducer located at the liquid container and configured to oscillate when current is supplied to the transducer via an ultrasonic generator, wherein the support structure resonates at the frequency via waves propagated through the liquid in response to the oscillation of the transducer.

[0111] Clause 9. The apparatus according to any one of the preceding clauses, further comprising an ultrasonic generator that supplies current to the transducer.

[0112] Clause 10. The apparatus according to any one of the preceding clauses, further comprising: a build plate configured to have an additively manufactured part and support structure formed thereon; an energy beam supply device; and a powder supply device configured to supply powder to be sintered or melted by the energy beam supply device; wherein once a first layer of powder is supplied by the powder supply device and sintered or melted by the energy beam supply device, the build plate is configured to retract, and the powder supply device is configured to supply a second layer of powder to be sintered or melted by the energy beam supply device.

[0113] Item 11. The device according to any one of the above items, wherein the energy beam supply device is a laser.

[0114] Item 12. A device for processing an additively manufactured component, the device comprising: a resonance device configured to resonate at least one of the additively manufactured component or an additively manufactured support structure connected to the additively manufactured component, wherein the resonance device is configured to resonate the support structure or the component at a frequency that separates unfused additive medium from the additively manufactured component.

[0115] Item 13. The device according to item 12, wherein the resonance device is a transducer.

[0116] Item 14. The device according to any one of the above items, wherein the transducer is configured to oscillate when current is supplied to the transducer via an ultrasonic generator, and wherein the transducer oscillates the additively manufactured component or support structure at the frequency.

[0117] Item 15. The device according to any one of the above items, wherein the transducer is configured to at least contact the additively manufactured component or support structure.

[0118] Item 16. The device according to any one of the above items, wherein the frequency is 200 - 900 Hertz (Hz).

[0119] Item 17. The device according to any one of the above items, further configured to resonate the support structure at a second resonance frequency, the second resonance frequency causing structural failure of the support structure and separation from the additively manufactured component.

[0120] Item 18. The device according to any one of the above items, wherein the second resonance frequency is 1100 Hz - 1900 Hz.

[0121] Item 19. The device according to any one of the above items, further comprising: a liquid container configured to contain liquid and the additively manufactured component and support structure; a transducer located at the liquid container and configured to oscillate when current is supplied to the transducer via an ultrasonic generator, wherein at least the additively manufactured component or support structure resonates at the frequency via waves propagated through the liquid in response to the oscillation of the transducer.

[0122] Item 20. The device according to any one of the above items, further comprising an ultrasonic generator that supplies current to the transducer.

[0123] Clause 21. The apparatus according to any one of the preceding clauses, wherein the transducer is configured to oscillate when current is supplied to the transducer via an ultrasonic generator, and wherein the transducer oscillates the additively manufactured component or support structure at the frequency.

[0124] Clause 22. The apparatus according to any one of the preceding clauses, further comprising: a build plate configured to have an additively manufactured component and a support structure formed thereon; an energy beam supply device; and a powder supply device configured to provide a powder build material to be melted by the energy beam supply device; wherein once a first layer of the powder build material is supplied by the powder supply device and melted by the energy beam supply device, the build plate is configured to retract, and the powder supply device is configured to provide a second layer of the powder build material to be sintered or melted by the energy beam supply device.

[0125] Clause 23. The apparatus according to any one of the preceding clauses, wherein the energy beam supply device is a laser.

[0126] Clause 24. A method of an additively manufactured construct and a support structure for mechanically supporting at least a portion of the construct, the method comprising: layer-by-layer melting of a powder build material to form the support structure; and layer-by-layer melting of the powder build material to form the construct; wherein the support structure is formed with a failure zone adjacent to the construct, and wherein the failure zone is configured to structurally fail and separate from the construct when subjected to resonance of a resonance device.

[0127] Clause 25. The method according to Clause 24, wherein the failure zone is formed by increasing or decreasing the volumetric energy density (VED) to introduce a structural defect in the support structure at the failure zone, and wherein the VED in joules per millimeter 3 (J / mm 3 ) is defined by the following equation: where E is the power of the energy source for melting the powder build material, S is the scanning speed of the energy source, L is the thickness of the unmelted powder build material, and H is the scanning pitch of the energy source for melting the powder build material.

[0128] Clause 26. The apparatus according to any one of the preceding clauses, wherein the VED at the failure zone is 40 J / mm 3 -80 J / mm 3 .

[0129] Clause 27. The apparatus according to any one of the preceding clauses, wherein the VED at the failure zone is 1 J / mm 3 -25 J / mm 3 .

[0130] Clause 28. The method according to any one of the above clauses, wherein the failure zone is one or more layers of the support structure that contact the building member and are to be removed from the building member.

[0131] Clause 29. The method according to any one of the above clauses, wherein layer-by-layer melting of the powder building material to form the support structure includes: providing a layer of powder building material via a powder supply device and melting the powder building material via a laser or an electron beam to form a failure zone layer of the support structure, and wherein layer-by-layer melting of the powder building material to form the building member includes: providing a layer of the powder building material above the failure zone layer of the support structure via the powder supply device and melting the powder building material via the laser or the electron beam to form a building member layer supported by the failure zone layer of the support structure.

[0132] Clause 30. The method according to any one of the above clauses, wherein the failure zone layer of the support structure is formed with a volume energy density (VED) that is 10% - 40% higher or lower than that of the building member layer, and the volume energy density is in joules per millimeter 3 (J / mm 3 ), and wherein VED is defined by the following equation: where E is the power of the laser or the electron beam, S is the scanning speed of the laser or the electron beam, L is the thickness of the unmelted powder building material, and H is the scanning pitch of the laser or the electron beam during melting of the powder building material.

[0133] Clause 31. The method according to any one of the above clauses, wherein the failure zone layer is formed with a VED that is 20% - 40% higher than that of the building member layer.

[0134] Clause 32. The method according to any one of the above clauses, wherein the failure zone layer is formed with a VED that is 20% - 40% lower than that of the building member layer.

[0135] Clause 33. The method according to any one of the above clauses, further comprising: resonating the support structure via a resonance device, wherein resonating the support structure causes structural failure of the support structure and separation from the building member at the failure zone.

[0136] Clause 34. The method according to any one of the above clauses, further comprising: resonating at least the support structure or the building member via a resonance device, wherein resonating at least the support structure or the building member causes separation of the unmelted powder building material from the building member.

[0137] Article 35. A non - transitory computer - readable medium storing computer - executable instructions for additive manufacturing, the instructions being executable by a processor to control an additive manufacturing apparatus to perform: layer - by - layer melting of a powder build material to form a support structure of a build; and layer - by - layer melting of the powder build material to form the build; wherein the support structure is formed with a failure zone adjacent to the build, and wherein the failure zone is configured to structurally fail and separate from the build when subjected to resonance of a resonance device.

[0138] Article 36. The non - transitory computer - readable medium storing computer - executable instructions according to Article 35, wherein the instructions are further executable by a processor to control an additive manufacturing device to increase or decrease a volume energy density (VED) to introduce a structural defect in the support structure at the failure zone, wherein the VED in joules per millimeter 3 (J / mm 3 ) is defined by the following equation: where E is the power of an energy source for melting the powder build material, S is the scanning speed of the energy source, L is the thickness of the non - melted powder build material, and H is the scanning pitch used when melting the powder build material via the energy source.

[0139] Article 37. The non - transitory computer - readable medium storing computer - executable instructions according to any one of the above articles, wherein the VED at the failure zone is 40 J / mm 3 - 80 J / mm 3 .

[0140] Article 38. The non - transitory computer - readable medium storing computer - executable instructions according to any one of the above articles, wherein the VED at the failure zone is 1 J / mm 3 - 25 J / mm 3 .

[0141] Article 39. The non - transitory computer - readable medium storing computer - executable instructions according to any one of the above articles, wherein the failure zone is one or more layers of the support structure that contact the build and are to be removed from the build.

[0142] Article 40. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing, wherein forming the support structure by layer-wise melting of a powder build material includes: providing the layer of the powder build material via a powder supply device and forming a failed region layer of the failed region of the support structure by melting the powder build material via a laser or an electron beam, and wherein forming the build part by layer-wise melting of the powder build material includes: providing the layer of the powder build material above the failed region layer of the support structure via the powder supply device and forming a build part layer supported by the failed region layer of the support structure by melting the powder build material via the laser or the electron beam.

[0143] Article 41. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to any one of the above articles, wherein the failed region layer is formed with a volume energy density (VED) that is 10%-40% higher or lower than that of the build part layer, and the volume energy density is in joules per millimeter 3 (J / mm 3 ), and wherein VED is defined by the following equation: where E is the power of the laser or the electron beam, S is the scanning speed of the laser or the electron beam, L is the thickness of the unmelted powder build material, and H is the scanning pitch of the laser or the electron beam when melting the powder build material.

[0144] Article 42. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to any one of the above articles, wherein the failed region layer is formed with a VED that is 20%-40% higher than that of the build part layer.

[0145] Article 43. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to any one of the above articles, wherein the failed region layer is formed with a VED that is 20%-40% lower than that of the build part layer.

[0146] Article 44. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to any one of the above articles, further including: resonating the support structure via a resonance device, wherein resonating the support structure causes structural failure of the support structure and separation from the build part at the failed region.

[0147] Article 45. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to any one of the above articles, further including: resonating at least the support structure or the build part via a resonance device, wherein resonating at least the support structure or the build part causes separation of the unmelted powder build material from the build part.

[0148] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these exemplary embodiments presented in this disclosure will be apparent to those skilled in the art, and the concepts disclosed herein can be applied to other support structures and systems and methods for removing support structures. Accordingly, the claims are not intended to be limited to the exemplary embodiments presented throughout this disclosure, but rather to the full scope consistent with the language of the claims. All structural and functional equivalents of the elements of the exemplary embodiments described throughout this disclosure (known or later to be known to those of ordinary skill in the art) are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public, whether or not such disclosure is explicitly recited in the claims. No claim element shall be construed under the provisions of 35 U.S.C. § 112(f) or similar laws in the applicable jurisdiction, unless the element is expressly recited using the phrase "means for" or, in the case of a method claim, the element is recited using the phrase "step for".

[0149] Equation Table 038191.00962

[0150]

[0151]

[0152] where E is the modulus of elasticity, I is the moment of inertia of the area, L is the length, and ρ is the mass density (mass / length).

[0153] P is the applied force

[0154] Note that a beam free at both ends and a beam fixed at both ends have the same formula.

[0155] The derivations and examples are given in Appendix of Table 2.

[0156]

[0157]

[0158] References

[0159] 1. T. Irvine, Application of the Newton - Raphson Method to Vibration Problems, Revision E, Vibration data, 2010. Appendix A

[0160] Cantilever beam Ⅰ

[0161] Consider a mass mounted at the end of a cantilever beam. Assume that the end mass is much larger than the mass of the beam.

[0162]

[0163] Figure A-1

[0164] E is the modulus of elasticity.

[0165] I is the moment of inertia of the area.

[0166] L is the length.

[0167] g is the gravity.

[0168] m is the mass.

[0169] The free body diagram of the system is

[0170]

[0171] Figure A-2

[0172] R is the reaction force.

[0173] M R is the reaction bending moment.

[0174] Apply Newton's law for static equilibrium.

[0175] +↑∑Force = 0 (A-1)

[0176] R - mg = 0 (A-2)

[0177] R = mg(A-3)

[0178] At the left boundary,

[0179]

[0180] M R -mgL = 0(A-5)

[0181] M R = mgL(A-6)

[0182] Now consider a segment of the beam starting from the left boundary.

[0183]

[0184] Figure A-3

[0185] V is the shear force.

[0186] M is the bending moment.

[0187] y is the deflection at the x position.

[0188] Sum the moments on the right side of the segment.

[0189]

[0190] MR - Rx - M = 0 (A - 8)

[0191] M = M R -Rx (A - 9)

[0192] The moment M and the deflection y are related by the following equation

[0193] M = EIy″ (A - 10)

[0194] EIy″ = M R -Rx (A - 11)

[0195] EIy″ = mgL - mgx (A - 12)

[0196] EIy″ = mg(L - x) (A - 13)

[0197]

[0198] Integrating gives,

[0199]

[0200] Note that "a" is the integration constant.

[0201] Integrating again,

[0202]

[0203] The boundary condition at the left end is

[0204] y(0) = 0 (zero displacement) (A - 17) Thus

[0205] b = 0 (A - 18) Another boundary condition is

[0206] y′(0) = 0 (zero slope) (A - 19)

[0207] Applying the boundary conditions to equation (A - 16) gives,

[0208] a = 0 (A - 20) The resulting deflection equation is

[0209]

[0210] The deflection at the right end is

[0211]

[0212] Recall that Hooke's law for a linear spring is,

[0213] F = ky(A - 24) where F is the force.

[0214] k is the stiffness.

[0215] The stiffness is thus

[0216] k = F / y(A - 25)

[0217] The force at the end of the beam is mg. The stiffness at the end of the beam is

[0218]

[0219] The formula for the natural frequency fn of a single - degree - of - freedom system is

[0220]

[0221] The mass term m is the mass at the end of the beam. The natural frequency of a cantilever beam with an end mass can be obtained by substituting Equation (A - 27) into (A - 28).

[0222]

[0223] Appendix B

[0224] Cantilever beam Ⅱ

[0225] Consider a cantilever beam with a mass per unit length of ρ. Assume the beam has a uniform cross - section. Determine the natural frequency.

[0226] Also find the effective mass, where the distributed mass is represented by a discrete end mass.

[0227]

[0228] Figure B - 1

[0229] The governing differential equation is

[0230]

[0231] The boundary conditions at the fixed end x = 0 are

[0232] y(0) = 0 (zero displacement) (B - 2)

[0233]

[0234] The boundary conditions at the free end x = L are

[0235]

[0236] Propose a quarter - cosine - wave solution.

[0237]

[0238]

[0239] The solution proposed satisfies all the boundary conditions except that the shear force is zero at the right end. Despite one defect, the solution is still accepted as an approximate solution for the deflection shape.

[0240] The Rayleigh Method is used to solve for the natural frequency. The total potential energy and the total kinetic energy must be determined.

[0241] The total potential energy P in the beam is

[0242]

[0243] By substituting

[0244]

[0245] The total kinetic energy T is

[0246]

[0247]

[0248] Now equate the potential energy term and the kinetic energy term

[0249]

[0250]

[0251] Recall that the stiffness at the free end of a cantilever beam is

[0252]

[0253] The effective mass m at the end of the beam eff Thus is

[0254]

[0255] m eff = 0.2235ρL(B - 38)

[0256] Appendix C

[0257] Cantilever beam Ⅲ

[0258] Consider a cantilever beam where both the mass of the beam and the end mass are important.

[0259]

[0260] Figure C - 1

[0261] Total mass m t can be calculated using Equation (B - 38).

[0262] m t = 0.2235pL + m(C - 1)

[0263] In addition, the stiffness at the free end of the cantilever beam is

[0264]

[0265] The natural frequency is thus

[0266]

[0267] Appendix D

[0268] Cantilever beam IV

[0269] This part is a repetition of Part II, but an exact solution is obtained for the differential equation. However, the differential equation itself is only an approximation of the actual situation.

[0270]

[0271] Figure D - 1

[0272] The governing differential equation is

[0273]

[0274] Note that this equation neglects shear deformation and rotational inertia.

[0275] Separate the dependent variables

[0276] y(x, t) = Y(x)T(t) (D - 2)

[0277]

[0278] Let C be a constant

[0279]

[0280] Separate the time variable.

[0281]

[0282] Separate the space variable.

[0283]

[0284] The solution of Equation (D - 10) is

[0285] Y(x) = a1 sinh(βx) + a2 cosh(βx) + a3 sin(βx) + a4 cos(βx) (D - 11)

[0286]

[0287] Substitute (D - 15) and (D - 11) into (D - 10).

[0288]

[0289] If the following conditions are satisfied, the equation holds

[0290]

[0291] The boundary conditions at the fixed end x = 0 are

[0292] Y(0) = 0 (zero displacement) (D - 20)

[0293]

[0294] The boundary conditions at the free end x = L are

[0295]

[0296] Apply formula (D - 20) to (D - 11)

[0297] a2 + a4 = 0 (D - 24)

[0298] a4 = -a2 (D - 25)

[0299] Apply formula (D - 21) to (D - 12)

[0300] a1 + a3 = 0 (D - 26)

[0301] a3 = -a1 (D - 27)

[0302] Apply formula (D - 22) to (D - 13)

[0303] a1 sinh(βL) + a2 cosh(βL) - a3 sin(βL) - a4 cos(βL) = 0 (D - 28)

[0304] Apply formula (D - 23) to (D - 14)

[0305] a1cosh(BL) + a2sinh(BL) - a3cos(BL) + a4sin(BL) = 0 (D - 29)

[0306] Apply formulas (D - 25) and (D - 27) to (D - 28)

[0307] a1 sinh(βL) + a2 cosh(βL) + a1 sin(βL) + a2 cos(βL) = 0 (D - 30)

[0308] a1{sin(βL) + sinh(βL)} + a2{cos(βL) + cosh(βL)} = 0 (D - 31)

[0309] Apply equations (D - 25) and (D - 27) to (D - 29).

[0310] a1 cosh(βL) + a2 sinh(βL) + a1 cos(βL) - a2 sin(βL) = 0 (D - 32)

[0311] a1{cos(βL) + cosh(βL)} + a2{-sin(βL) + sinh(βL)} = 0 (D - 33)

[0312] Arrange (D - 31) and (D - 33) into matrix form.

[0313]

[0314] By inspection, equation (D - 34) can only be satisfied when a1 = 0 and a2 = 0. To obtain non - trivial solutions, set the determinant to zero.

[0315] {-sin 2 (βL) + sinh 2 (βL)}-{cos(βL) + cosh(βL)} 2 = 0 (D - 35)

[0316] {-sin 2 (BL) + sinh 2 (BL)}-{cos 2 (BL) + 2cos(BL)cosh(BL) + cosh 2 (BL)} = 0

[0317] (D - 36)

[0318] -sin 2 (βL) + sinh 2 (βL) - cos 2 (βL) - 2cos(βL)cosh(βL) - cosh 2 (βL) = 0 (D - 37)

[0319] -2 - 2cos(βL)cosh(βL) = 0 (D - 38)

[0320] 1 + cos(βL)cosh(βL) = 0 (D - 39)

[0321] cos(βL)cosh(βL) = -1 (D - 40)

[0322] There are multiple roots that satisfy Equation (D - 40). Therefore, subscripts should be added as shown in Equation (D - 41).

[0323] cos(β n L)cosh(β n L) = -1 (D - 41)

[0324] The subscripts are integer indices. The roots can be determined by a combination of graphical and numerical methods. The Newton - Raphson method is an example of an approximate numerical method. The roots of Equation (D - 41) are summarized in Table D - 1, the data of which is taken from Reference 1.

[0325]

[0326] Note: The root value formula for n ≥ 3 is approximate.

[0327] Rearrange Equation (D - 19) as follows

[0328]

[0329] Substitute (D - 42) into (D - 8)

[0330]

[0331] Equation (D - 43) satisfies the following conditions

[0332]

[0333] Therefore, the natural frequency term ω n is

[0334]

[0335] Substitute the value of the fundamental frequency from Table D - 1

[0336]

[0337] Substitute the value of the second root from Table D - 1

[0338]

[0339] f2 = 6.268f1 (D - 50)

[0340] Compare Equation (D - 47) with the approximate Equation (B - 33).

[0341] SDOF model approximation

[0342] Therefore, for the basic mode, the effective mass m at the end of the beam eff is

[0343]

[0344] m eff = 0.2427pL (SDOF approximation) (D-54)

[0345] Eigenvalue

[0346]

[0347] Note: The root formula for n ≥ 5 is approximate.

[0348] Normalized eigenvector

[0349] Normalize the eigenvector in the following way

[0350]

[0351] For simplicity, the calculation steps are omitted. The resulting normalized eigenvector is

[0352]

[0353] The normalized mode shape can be expressed as

[0354]

[0355] where

[0356]

[0357] Participation factor

[0358] The participation factor for a constant mass density is

[0359]

[0360] The participation factor obtained from numerical calculation is

[0361]

[0362] The participation factor is dimensionless.

[0363] Effective modal mass

[0364] The effective modal mass is

[0365]

[0366] The eigenvectors have been normalized such that

[0367]

[0368] Therefore,

[0369]

[0370] The effective modal mass values are obtained through numerical calculation.

[0371] m eff,1 = 0.6131pL(D - 70)

[0372] m eff,2 = 0.1883pL(D - 71)

[0373] m eff,3 = 0.06474pL(D - 72)

[0374] m eff,4 = 0.03306pL(D - 73)

[0375] Appendix E

[0376] Simply supported beam Ⅰ at both ends

[0377] Consider a simply supported beam with a discrete mass at the midpoint. Assume that the mass of the beam itself is negligible.

[0378]

[0379] Figure E - 1

[0380] The free - body diagram of the system is

[0381]

[0382] Figure E - 2

[0383] For the static equilibrium problem, apply Newton's law

[0384] +↑∑Force = 0 (E - 1)

[0385] Ra + Rb - mg = 0 (E - 2)

[0386] Ra = mg - Rb (E - 3)

[0387] At the left boundary,

[0388]

[0389] RbL - mgL1 = 0 (E - 5)

[0390] Rb = mg(L1 / L)(E - 6a)

[0391] Rb = (1 / 2)mg(E - 6b)

[0392] Substitute equation (E - 6) into (E - 3).

[0393] Ra = mg - (1 / 2)mg(E - 7)

[0394] Ra = (1 / 2)mg(E - 8)

[0395]

[0396] Sum the moments at the right side of this section.

[0397]

[0398] -R a x + mg <x-l1>-M = 0 (E - 10) Note that, <x-l1>Represents the following step function

[0399]

[0400] M = -R a x + mg <x-l1>(E-12)

[0401] M = -(1 / 2)mgx + mg <x-l1>(E-13)

[0402] M = [-(1 / 2)x + <x-l1>[mg](E-14)

[0403] EIy″=[-(1 / 2)x+ <x-l1>[mg](E-15)

[0404]

[0405] The boundary condition on the left side is

[0406] y(0) = 0 (E-19a)

[0407] This requires

[0408] b = 0 (E-19b)

[0409] Therefore

[0410]

[0411] The boundary condition on the right side is

[0412] y(L) = 0 (E-21)

[0413]

[0414] Now substitute the constants into the displacement function

[0415]

[0416] The displacement at the center is

[0417]

[0418]

[0419] Recall that Hooke's law for a linear spring is

[0420] F = ky (E-36)

[0421] F is the force.

[0422] k is the stiffness.

[0423] The stiffness is thus

[0424] k = F / y (E-37)

[0425] The unit of the force at the center of the beam is mg. The stiffness at the center of the beam is

[0426]

[0427] The formula for the natural frequency fn of a single-degree-of-freedom system is

[0428]

[0429] The mass term m is the mass at the center of the beam.

[0430]

[0431] Appendix F

[0432] Beam Ⅱ simply supported at both ends

[0433] Consider a simply supported beam as shown in Figure F-1.

[0434]

[0435] Figure F-1

[0436] Recall that the governing differential equation is

[0437]

[0438] The spatial solution for section D is

[0439] Y(x) = a1 sinh(βx) + a2 cosh(βx) + a3 sin(βx) + a4 cos(βx) (F-2)

[0440]

[0441] The boundary conditions at the left end x = 0 are

[0442] Y(0) = 0 (zero displacement) (F-4)

[0443]

[0444] The boundary conditions at the right end x = L are

[0445] Y(L) = 0 (zero displacement) (F-6)

[0446]

[0447] Apply the boundary condition (F-4) to (F-2).

[0448] a2 + a4 = 0 (F-8)

[0449] a4 = -a2 (F-9)

[0450] Apply the boundary condition (F-5) to (F-3).

[0451] a2 - a4 = 0 (F-10)

[0452] a2 = a4 (F-11)

[0453] Equations (F-8) and (F-10) can be satisfied if

[0454] a2 = 0 (F-12)

[0455] and

[0456] a4 = 0(F - 13)

[0457] Therefore, the spatial equation simplifies to

[0458] Y(x) = a1 sinh(βx) + a3 sin(βx)(F - 14)

[0459]

[0460] Apply the boundary conditions (F - 6) to (F - 14).

[0461] a1 sinh(βL) + a3 sin(βL) = 0(F - 16)

[0462] Apply the boundary conditions (F - 7) to (F - 15).

[0463] a1β 2 sinh(βL) - a3β 2 sin(βL) = 0(F - 17)

[0464] a1 sinh(βL) - a3 sin(βL) = 0(F - 18)

[0465]

[0466] By inspection, the equation (F - 19) is satisfied only when a1 = 0 and a3 = 0. To obtain a non - trivial solution, set the determinant to zero.

[0467] -sin(βL)sinh(βL) - sin(βL)sinh(βL) = 0(F - 20)

[0468] -2sin(βL)sinh(βL) = 0(F - 21)

[0469] sin(βL)sinh(βL) = 0(F - 22)

[0470] The equation (F - 22) is satisfied if the following condition is met

[0471] β n L = nπ, n = 1, 2, 3, …(F - 23)

[0472]

[0473] The natural frequency term ω n is

[0474]

[0475] SDOF approximation

[0476] Now calculate the effective mass at the center of the beam at the fundamental frequency.

[0477]

[0478] Review the natural frequency equation for a single-degree-of-freedom system.

[0479]

[0480] Review the beam stiffness at the center for Equation (E-39).

[0481]

[0482] Substitute Equation (F-31) into (F-30).

[0483]

[0484] Substitute (F-32) into (F-29).

[0485]

[0486]

[0487] For the first model, the effective mass at the center of the beam is

[0488]

[0489] Normalized eigenvector

[0490] The eigenvector and its second derivative at this time are

[0491] Y(x) = a1 sinh(βx) + a3 sin(βx) (F-38)

[0492]

[0493] Taking the derivative of the eigenvector requires some creativity. Review

[0494] Y(L) = 0 (zero displacement) (F-40)

[0495]

[0496] Therefore,

[0497]

[0498] The sin(nπ) term is always zero. Therefore, a1 = 0.

[0499] The eigenvector for all models n is

[0500] Y n (x) = a n sin(nπx / L)(F - 44)

[0501] The eigenvectors are mass-normalized as follows

[0502]

[0503]

[0504] Participation factor

[0505] The participation factor for a constant mass density is

[0506]

[0507] Effective modal mass

[0508] The effective modal mass is

[0509]

[0510] The eigenvectors have been normalized such that

[0511]

[0512] Therefore,

[0513]

[0514] Appendix G

[0515] Beam free at both ends

[0516] Consider a uniform beam with free boundary conditions at both ends.

[0517]

[0518] Figure G-1

[0519] The governing differential equation is

[0520]

[0521] Note that this equation neglects shear deformation and rotational inertia.

[0522] The following equation is obtained using the method in Appendix D

[0523]

[0524] The proposed solution is

[0525] Y(x) = a1 sinh(βx) + a2 cosh(βx) + a3 sin(βx) + a4 cos(βx) (G-3)

[0526]

[0527] Apply the boundary conditions.

[0528]

[0529] a2 - a4 = 0 (G-8)

[0530] a4 = a2 (G-9)

[0531]

[0532] a1 - a3 = 0 (G-11)

[0533] a3 = a1 (G-12)

[0534]

[0535] a1 [sinh(βL) - sin(βL)] + a2 [cosh(βL) - cos(βL)] = 0 (G-16)

[0536]

[0537] a1 [cosh(βL) - cos(βL)] + a2 [sinh(βL) + sin(βL)] = 0 (G-18)

[0538] Equations (G-16) and (G-18) can be arranged in matrix form.

[0539]

[0540] Set the determinant to zero.

[0541] [sinh(βL) - sin(βL)][sinh(βL) + sin(βL)] - [cosh(βL) - cos(βL)] 2 = 0 (G-20)

[0542] sinh 2 (βL) - sin 2 (βL) - cosh 2 (βL) + 2cosh(βL)cos(βL) - cos 2 (βL) = 0 (G-21)

[0543] +2cosh(βL)cos(βL)-2 = 0 (G-22)

[0544] cosh(βL)cos(βL)-1 = 0 (G-23)

[0545] The roots can be obtained via the Newton-Raphson method, as in Ref. 1.

[0546] A beam free at both ends has a rigid body mode with zero frequency, corresponding to βL = 0.

[0547] The second root is

[0548] βL = 4.73004 (G-24)

[0549]

[0550]

[0551] The third root is

[0552] βL = 7.85320 (G-28)

[0553]

[0554] ω3 = 2.757ω2 (G-32)

[0555] The fourth root is

[0556] βL = 10.9956 (G-33)

[0557]

[0558] ω4 = 5.404ω2 (G-37)

[0559] Eigenvector

[0560]

[0561]

[0562]

[0563] The following formulas for the derivation of the vibration modes and coefficients are only applicable to elastic modes (where βL > 0).

[0564] Equation (G-18) can be expressed as

[0565]

[0566] Recall

[0567] a4 = a2 (G-40)

[0568] a3 = a1(G - 41)

[0569] Therefore, the displacement mode shape is

[0570] Y(x) = a1[sinh(βx) + sin(βx)] + a2[cosh(βx) + cos(βx)]

[0571] (G - 42)

[0572]

[0573] Modify the mode shape in the following way.

[0574]

[0575] Normalize the eigenvector with respect to mass.

[0576]

[0577] The eigenvector is mass - normalized for carried out mass normalization.

[0578] Therefore

[0579]

[0580] The first - order derivative is

[0581]

[0582] The second - order derivative is

[0583]

[0584] For a constant mass density, the participation factor is

[0585]

[0586] The participation factor is obtained by numerical calculation.

[0587] The results for the rigid - body mode are,

[0588] Γ n = 0 n>1 (G - 50)

[0589] Appendix H

[0590] Pipe example

[0591] Consider a steel pipe with an outer diameter of 2.2 inches and a wall thickness of 0.60 inches. The length is 20 feet. Find the natural frequencies for two boundary conditions (simply supported and fixed at both ends).

[0592] The area moment of inertia is

[0593]

[0594] D o = 2.2 in (H - 2)

[0595] D i = 2.2 - 2(0.6) in (H - 3)

[0596] D i = 2.2 - 1.2 in (H - 4)

[0597] D i = 1.0 in (H - 5)

[0598]

[0599] I = 1.101 in 4 (H - 7)

[0600] The modulus of elasticity is

[0601]

[0602] The mass density is

[0603] ρ = mass per unit length (H - 9)

[0604]

[0605] The natural frequency in the case of simply supported is

[0606]

[0607] f1 = 3.34 Hz (simply supported) (H - 16)

[0608] The natural frequency in the case of fixed at both ends is

[0609]

[0610] f1 = 7.58 Hz (fixed at both ends) (H - 19)

[0611] Appendix I

[0612] Suborbital rocket vehicle

[0613] Consider a rocket vehicle with the following characteristics.

[0614] Mass = 14078.9 lbm (at time = 0 seconds)

[0615] L = 372.0 inches

[0616]

[0617] The average stiffness is

[0618] EI = 63034(10 6 ) lbf in∧2

[0619] The aircraft behaves like a beam free at both ends during flight. Therefore

[0620]

[0621] f1 = 20.64 Hz (at time t = 0 seconds) (I-3) Note that the fundamental frequency during flight decreases as the aircraft expels propellant mass.

[0622] Appendix J

[0623] Beam fixed at both ends

[0624] Consider a beam fixed at both ends with a uniform mass density and a uniform cross-section.

[0625] The governing differential equation is

[0626]

[0627] The spatial equation is

[0628]

[0629] The boundary conditions for a beam fixed at both ends are:

[0630] Y(0) = 0 (J-3)

[0631]

[0632] Y(L) = 0 (J-5)

[0633]

[0634] The eigenvector has the following form

[0635] Y(x) = a1 sinh(βx) + a2 cosh(βx) + a3 sin(βx) + a4 cos(βx) (J-7)

[0636]

[0637] Y(0) = 0 (J-10)

[0638] a2 + a4 = 0 (J-11)

[0639] -a2 = a4 (J-12)

[0640]

[0641] a1β + a3β = 0 (J - 14)

[0642] a1 + a3 = 0 (J - 15)

[0643] -a1 = a3 (J - 16)

[0644] Y(x) = a1[sinh(βx) - sin(βx)] + a2[cosh(βx) - cos(βx)] (J - 17)

[0645]

[0646] Y(L) = 0 (J - 19)

[0647] a1[sinh(βL) - sin(βL)] + a2[cosh(βL) - cos(βL)] = 0 (J - 20)

[0648]

[0649] a1β[cosh(βL) - cos(βL)] + a2β[sinh(βL) + sin(βL)] = 0 (J - 22)

[0650] a1[cosh(βL) - cos(βL)] + a2[sinh(βL) + sin(βL)] = 0 (J - 23)

[0651]

[0652] [sinh(βL) - sin(βL)][sinh(βL) + sin(βL)] - [cosh(βL) - cos(βL)] 2 = 0 (J - 26)

[0653] sinh 2 (βL) - sin 2 (βL) - cosh 2 (βL) + 2cos(βL)cosh(βL) - cos 2 (βL) = 0 (J - 27)

[0654] 2cos(βL)cosh(βL) - 2 = 0 (J - 28)

[0655] cos(βL)cosh(βL) - 1 = 0 (J - 29)

[0656] The roots can be obtained by the Newton-Raphson method, as in Reference 1. The first root is

[0657] βL = 4.73004(J - 30)

[0658]

[0659] a1[cosh(βL) - cos(βL)] = -a2[sinh(βL) + sin(βL)](J - 35)

[0660] Let a2 = 1 (J - 36)

[0661] a1[cosh(βL) - cos(βL)] = -[sinh(βL) + sin(βL)](J - 37)

[0662]

[0663] The unnormalized vibration mode of a beam fixed at both ends is

[0664]

[0665] where

[0666]

[0667] The eigenvalues are

[0668] n <![CDATA[β n L]]> 1 4.73004 2 7.85321 3 10.9956 4 14.13717 5 17.27876

[0669] When n > 5

[0670]

[0671] Normalize the eigenvector

[0672] The eigenvectors are mass-normalized in the following way

[0673]

[0674] The mass normalization is satisfied by the following

[0675]

[0676] where

[0677]

[0678] The first derivative is

[0679]

[0680] The second derivative is

[0681]

[0682] The participation factor of the participation factor with constant mass density is

[0683]

[0684] The participation factors obtained by numerical calculation are

[0685]

[0686] Γ2 = 0 (J - 55)

[0687]

[0688] Γ4 = 0 (J - 57)

[0689]

[0690] The participation factor is dimensionless.

[0691] Appendix K

[0692] Beam fixed - hinged

[0693] Consider a beam fixed at one end and hinged at the other end, as shown in Figure K - 1.

[0694]

[0695] Figure K - 1

[0696] Recall that the governing differential equation is

[0697]

[0698] The spatial solution is

[0699] Y(x) = a1 sinh(βx) + a2 cosh(βx) + a3 sin(βx) + a4 cos(βx) (K - 2)

[0700]

[0701] The boundary condition at the left end x = 0 is

[0702] Y(0) = 0 (zero displacement) (K - 5)

[0703]

[0704] The boundary condition at the right end x = L is

[0705] Y(L) = 0 (zero displacement) (K - 7)

[0706]

[0707] Apply the boundary condition (K-5).

[0708] a2 + a4 = 0 (K-9)

[0709] a4 = -a2 (K-10)

[0710] Apply the boundary condition (K-6).

[0711] a1 + a3 = 0 (K-11)

[0712] a3 = -a1 (K-12)

[0713] Apply the result of the left boundary condition to the displacement function.

[0714] Y(x) = a1[sinh(βx) - sin(βx)] + a2[cosh(βx) - cos(βx)] (K-13)

[0715] Apply the boundary condition (K-7).

[0716] a1[sinh(βL) - sin(βL)] + a2[cosh(βL) - cos(βL)] = 0 (K-14)

[0717] Apply the result of the left boundary condition to the second derivative of the displacement function.

[0718]

[0719] Apply the boundary condition (K-7).

[0720] a1β 2 [sinh(βL) + sin(βL)] + a2β 2 [cosh(βL) + cos(βL)] = 0 (K-16)

[0721] a1[sinh(βL) + sin(βL)] + a2[cosh(βL) + cos(βL)] = 0 (K-17)

[0722]

[0723] [sinh(βL) - sin(βL)][cosh(βL) + cos(βL)] -

[0724] [sinh(βL) + sin(βL)][cosh(βL) - cos(βL)] = 0 (K-20)

[0725] sinh(βL)cos(βL)+sin(βL)cos(βL)-sin(βL)cosh(βL)-sin(βL)cos(βL)

[0726] -sinh(βL)cos(βL)+sinh(βL)cos(βL)-sin(βL)cosh(βL)+sin(βL)cos(βL)=0

[0727] (K-21)

[0728] 2sinh(βL)cos(βL)-2sin(βL)cosh(βL)=0(K-22)

[0729] sinh(βL)cos(βL)-sin(βL)cosh(βL)=0(K-23)

[0730] tanh(βL)-tan(βL)=0(K-24)

[0731] The eigenvector is

[0732]

[0733]

[0734] When n≥5,

[0735]

[0736] The unnormalized eigenvector is

[0737]

[0738] The mass-normalized eigenvector is

[0739]

[0740] Participation factor

[0741] The participation factor with a constant mass density is

[0742]

[0743]

[0744] The participation factor obtained by numerical calculation is

[0745]

[0746] The participation factor is dimensionless.

Claims

1. An apparatus for processing an additively manufactured part and a support structure, the apparatus comprising: A resonance device for resonating at least the additively manufactured part or the support structure, wherein the resonance device is configured to resonate the support structure at a frequency that causes structural failure of the support structure and separation from the additively manufactured part.

2. The device according to claim 1, wherein, The resonance device is a transducer.

3. The device according to claim 2, wherein The transducer is configured to oscillate when current is supplied to the transducer via an ultrasonic generator, wherein the transducer oscillates at least the additively manufactured part or the support structure at the frequency.

4. The apparatus according to claim 3, wherein, The transducer is configured to at least contact the additively manufactured part or the support structure.

5. The device according to claim 1, wherein The frequency is 1100 - 1900 Hertz (Hz).

6. The apparatus according to claim 1, further configured to resonate at least the additively manufactured part or the support structure at a second resonance frequency that separates unfused additive medium from the additively manufactured part.

7. The apparatus according to claim 6, wherein The second resonance frequency is 200 Hz - 900 Hz.

8. The apparatus according to claim 1, further comprising: A liquid container configured to contain liquid and the additively manufactured part and the support structure; and A transducer located at the liquid container, configured to oscillate when current is supplied to the transducer via an ultrasonic generator, wherein the support structure resonates at the frequency via waves propagated through the liquid in response to the oscillation of the transducer.

9. The apparatus according to claim 8, further comprising an ultrasonic generator that supplies current to the transducer.

10. The apparatus according to claim 1, further comprising: A build plate configured to have an additively manufactured part and a support structure formed thereon; An energy beam supply device; and A powder supply device configured to supply powder to be sintered or melted by the energy beam supply device; wherein once a first layer of powder is supplied by the powder supply device and sintered or melted by the energy beam supply device, the build plate is configured to retract, and the powder supply device is configured to supply a second layer of powder to be sintered or melted by the energy beam supply device.

11. The device according to claim 10, wherein, The energy beam supply device is a laser.

12. An apparatus for processing an additively manufactured part, the apparatus comprising: A resonance device for resonating at least one of the additively manufactured part or an additively manufactured support structure connected to the additively manufactured part, wherein the resonance device is configured to resonate at least the support structure or the part at a frequency that separates unfused additive medium from the additively manufactured part.

13. The apparatus according to claim 12, wherein, The resonance device is a transducer.

14. The apparatus according to claim 13, wherein, The transducer is configured to oscillate when current is supplied to the transducer via an ultrasonic generator, wherein the transducer oscillates at least the additively manufactured part or the support structure at the frequency.

15. The apparatus according to claim 14, wherein The transducer is configured to at least contact the additively manufactured part or the support structure.

16. The apparatus according to claim 12, wherein The frequency is 200 - 900 Hertz (Hz).

17. The apparatus according to claim 12, further configured to resonate the support structure at a second resonance frequency that causes structural failure of the support structure and separation from the additive manufactured component.

18. The device according to claim 17, wherein, The second resonance frequency is 1100 Hz - 1900 Hz.

19. The apparatus according to claim 12, further comprising: A liquid container configured to contain a liquid and the additive manufactured component and the support structure; And A transducer located at the liquid container and configured to oscillate when an electric current is supplied to the transducer via an ultrasonic generator, wherein at least the additive manufactured component or the support structure resonates at the frequency via waves propagated through the liquid in response to the oscillation of the transducer.

20. The apparatus according to claim 19, further comprising an ultrasonic generator that supplies an electric current to the transducer.

21. The apparatus according to claim 13, wherein, The transducer is configured to oscillate when an electric current is supplied to the transducer via an ultrasonic generator, wherein the transducer oscillates at least the additive manufactured component or the support structure at the frequency.

22. The apparatus according to claim 12, further comprising: A build plate configured to have an additive manufactured component and a support structure formed thereon; An energy beam supply device; And A powder supply device configured to supply a powder build material to be melted by the energy beam supply device; wherein once a first layer of the powder build material is supplied by the powder supply device and melted by the energy beam supply device, the build plate is configured to retract, and the powder supply device is configured to supply a second layer of the powder build material to be sintered or melted by the energy beam supply device.

23. The device according to claim 22, wherein, The energy beam supply device is a laser.

24. A method of additive manufacturing a build component and a support structure for mechanically supporting at least a portion of the build component, the method comprising: Layerwise melting of a powder build material to form the support structure; And Layerwise melting of the powder build material to form the build component; wherein the support structure is formed with a failure zone adjacent to the build component, and the failure zone is configured to structurally fail and separate from the build component when resonated by a resonance device.

25. The method according to claim 24, wherein The failure zone is formed by increasing or decreasing the volumetric energy density (VED) to introduce structural defects at the failure zone in the support structure, where the VED in joules per millimeter 3 (J / mm 3 ) is defined by the following equation: Wherein E is the power of the energy source for melting the powder build material, S is the scanning speed of the energy source, L is the thickness of the unmelted powder build material, and H is the scanning pitch of the energy source for melting the powder build material.

26. The method according to claim 25, wherein, The VED at the failure area is 40 J / mm 3 -80 J / mm 3 .

27. The method according to claim 25, wherein, The VED at the failure area is 1 J / mm 3 -25 J / mm 3 .

28. The method according to claim 24, wherein The failure zone is one or more layers of the support structure that contact the build component and are to be removed from the build component.

29. The method according to claim 24, wherein Layerwise melting of the powder build material to form the support structure includes: Providing a layer of the powder build material via a powder supply device and melting the powder build material via a laser or an electron beam to form a failure zone layer of the support structure, and wherein layerwise melting of the powder build material to form the build component includes: Providing a powder build material layer above the failed zone layer of the support structure via the powder supply device and melting the powder build material via the laser or electron beam to form a build part layer supported by the failed zone layer of the support structure.

30. The method according to claim 29, wherein, The failure zone layer of the support structure is formed with a volume energy density (VED) that is 10%-40% higher or lower than the build height of the build member, and the volume energy density is in joules per millimeter 3 (J / mm 3 ), and wherein the VED is defined by the following equation: Wherein, E is the power of the laser or electron beam, S is the scanning speed of the laser or electron beam, L is the thickness of the unmelted powder build material, and H is the scanning pitch of the laser or electron beam during melting of the powder build material.

31. The method according to claim 30, wherein, The failed zone layer is formed with a VED that is 20%-40% higher than that of the build part layer.

32. The method according to claim 30, wherein, The failed zone layer is formed with a VED that is 20%-40% lower than that of the build part layer.

33. The method according to claim 24, further comprising: Resonating the support structure via a resonance device, wherein resonating the support structure causes structural failure of the support structure and separation from the build part at the failed zone.

34. The method according to claim 24, further comprising: Resonating at least the support structure or the build part via a resonance device, wherein resonating at least the support structure or the build part causes separation of the unmelted powder build material from the build part.

35. A non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing, the instructions being executable by a processor to control an additive manufacturing device to perform: Layered melting of a powder build material to form a support structure for a build part; and The powder building material is layer-by-layer melted to form the build; wherein, The support structure is formed with a failed zone adjacent to the build part, wherein the failed zone is configured to structurally fail and separate from the build part when subjected to resonance by a resonance device.

36. The non-transitory computer-readable medium storing computer-executable instructions according to claim 35, wherein, The instructions can be further executed by a processor to control an additive manufacturing device to increase or decrease a volumetric energy density (VED) to introduce a structural defect at the failure zone in a support structure, wherein the VED in joules per millimeter 3 (J / mm 3 ) is defined by the following equation: Wherein, E is the power of the energy source for melting the powder build material, S is the scanning speed of the energy source, L is the thickness of the unmelted powder build material, and H is the scanning pitch used when melting the powder build material via the energy source.

37. The non-transitory computer-readable medium storing computer-executable instructions according to claim 36, wherein, The VED at the failure zone is 40 J / mm 3 -80 J / mm 3 。 38. The non-transitory computer-readable medium storing computer-executable instructions according to claim 36, wherein, The VED at the failure zone is 1 J / mm 3 -25 J / mm 3 。 39. The non-transitory computer-readable medium storing computer-executable instructions according to claim 35, wherein, The failed zone is one or more layers of the support structure that contact the build part and are to be removed from the build part.

40. The non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to claim 35, wherein, Layered melting of a powder build material to form the support structure includes: Providing a powder build material layer via a powder supply device and melting the powder build material via a laser or electron beam to form a failed zone layer of the failed zone of the support structure, and wherein layered melting of the powder build material to form the build part includes: Providing a powder build material layer above the failed zone layer of the support structure via the powder supply device and melting the powder build material via the laser or electron beam to form a build part layer supported by the failed zone layer of the support structure.

41. The non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to claim 40, wherein, The failure zone layer has a volumetric energy density (VED) that is 10%-40% higher or lower than that of the build layer, and the volumetric energy density is in joules per millimeter 3 (J / mm 3 ), where VED is defined by the following equation: Wherein, E is the power of the laser or electron beam, S is the scanning speed of the laser or electron beam, L is the thickness of the unmelted powder build material, and H is the scanning pitch of the laser or electron beam for melting the powder build material.

42. The non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to claim 41, wherein, The failed zone layer is formed with a VED that is 20%-40% higher than that of the build part layer.

43. The non-transitory computer-readable medium storing computer-executable instructions for additive manufacturing according to claim 41, wherein, The failed zone layer is formed with a VED that is 20%-40% lower than that of the build part layer.

44. The non - transitory computer - readable medium storing computer - executable instructions for additive manufacturing according to claim 35, further comprising: Resonating the support structure via a resonance device, wherein resonating the support structure causes structural failure of the support structure and separation from the build part at the failure region.

45. The non - transitory computer - readable medium storing computer - executable instructions for additive manufacturing according to claim 35, further comprising: Resonating at least the support structure or the build part via a resonance device, wherein resonating at least the support structure or the build part causes separation of unfused powder build material from the build part.

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