Systems and methods for powder recycling in additive manufacturing

Abstract

The system includes a powder recycling system (PRS) executable via a processor and configured to receive one or more inputs for building a first mechanical part in a sintering system, the PRS further configured to retrieve a model configured to model recycling of sintered powder and apply the one or more inputs to the model to derive a time when excess unsintered powder remaining after printing the mechanical part through the sintering system using the sintered powder can be recycled to build a second mechanical part.

Description

[Technical Field]

[0001] The subject matter disclosed herein generally relates to systems incorporating powder recycling in additive manufacturing and methods for powder recycling in additive manufacturing. [Background technology]

[0002] Various machine components (e.g., turbomachinery components) are exposed to high-pressure and / or high-temperature fluid flows. For example, turbomachinery components may include gas turbine engine components such as compressors, combustors, and / or turbine components. Gas turbine engine components may include fuel nozzles, compressor blades, turbine blades, compressor wheels, turbine wheels, shroud segments, and combustor-to-turbine transition pieces, among others. These machine components may be manufactured using additive technologies, such as powder bed fusion techniques. For example, machine components may be manufactured by adding powder, which may be sequentially fused layer by layer to produce a desired three-dimensional (3D) part. As described in more detail below, reusing added powder in additive manufacturing may be useful. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent No. 7165334 Summary of the Invention

[0004] Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention; rather, these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below.

[0005] In a first embodiment, the system includes a powder recycling system (PRS) executable via a processor and configured to receive one or more inputs for building a first mechanical part in a sintering system, wherein the PRS is further configured to retrieve a model configured to model recycling of sintered powder and apply the one or more inputs to the model to derive a time at which excess unsintered powder remaining after printing the mechanical part through the sintering system using the sintered powder can be recycled to build a second mechanical part.

[0006] In a second embodiment, a method for manufacturing a mechanical part includes receiving, via a powder recycling system (PRS), one or more inputs for building a first mechanical part in a sintering system, and retrieving, via the PRS, a model configured to model recycling of the sintered powder. The method further includes deriving, via the PRS, a time during which excess unsintered powder remaining after printing the mechanical part through the sintering system using the sintered powder can be recycled to build a second mechanical part by applying the one or more inputs to the model.

[0007] In a third embodiment, a non-transitory computer-readable medium includes instructions that, when executed, cause a processor to receive, via a powder reuse system (PRS), one or more inputs for building a first mechanical part in a sintering system. The instructions, when executed, further cause the processor to retrieve, via the PRS, a model configured to model reuse of sintered powder, and derive, via the PRS, by applying the one or more inputs to the model, a time at which excess unsintered powder remaining after printing the mechanical part via the sintering system using the sintered powder can be reused to build a second mechanical part.

[0008] These and other features, aspects, and advantages of the present invention will become better understood from the following detailed description when read in conjunction with the accompanying drawings, in which like reference numerals represent like parts throughout. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram of an embodiment of a turbomachine system including parts that may be sintered via a sintering system. [Figure 2] FIG. 1 is a block diagram of an embodiment of a sintering system including a powder recycling system. [Figure 3] 1 is a flow chart of one embodiment of a process by which sintered powder may be reused. DETAILED DESCRIPTION OF THE INVENTION

[0010] One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation will be described herein. It will be appreciated that the development of such an actual implementation, like any engineering or design project, will require numerous implementation-specific decisions to achieve the developer's particular goals, including, for example, compliance with system-related and business-related constraints, which may vary from implementation to implementation. Moreover, it will be appreciated that such a development effort may be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0011] When introducing elements of various embodiments of the invention, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0012] As described in detail below, layered structures (e.g., of mechanical parts) can be manufactured using additive methods, which can include the use and reuse of specific powders. The powders can include metal powders, ceramic powders, ceramic-metal (cermet) powders, polymer powders, or any combination thereof, depending on the specific additive method and the part being additively manufactured. For example, metal powders such as steel (e.g., stainless steel, titanium, nickel-based alloys, aluminum, etc.) can be used via certain laser melting systems of additive manufacturing systems. The manufactured parts can be all or part of a mechanical part, including mechanical parts that can be exposed to thermal and mechanical stresses over extended periods of time. In some embodiments, such mechanical parts can be incorporated into turbomachinery, rotary machinery, hot gas path machinery, or some other machinery. For example, the turbomachinery can include a compressor, a pump, a turbine, or a combination thereof. The mechanical part can be a part of a turbine of the turbomachinery, which can include a gas turbine, a steam turbine, a hydroelectric turbine, and / or a wind turbine. The layered structure may be, for example, all or a portion of a turbomachinery component such as a blade (e.g., a rotating blade or a stator vane), a turbine nozzle, a turbine frame, a seal, a combustor liner, a combustor cap, a fuel nozzle, a compressor blade, a compressor wheel, a turbine wheel, a shroud segment, a gas premixer, a liquid fuel injector, or a combustor-to-turbine transition piece.

[0013] In particular, in embodiments of the present disclosure, the sintering system of the additive manufacturing system may include specific techniques for recycling powder. In accordance with the present disclosure, the term "sintering" includes a reference to the specific manufacturing technique used to achieve a bonded layer, and "bonded layer" refers to a layer densified, for example, from a powder. In other words, sintering may be a manufacturing process that bonds powder into a sintered or bonded layer (e.g., by direct metal laser sintering (DMLS), direct metal laser melting (DMLM), selective laser sintering (SLS), electron beam melting (EBM), or any other suitable additive manufacturing process). The powder may include a metal that can be sintered by one of the aforementioned processes. By recycling powder to form a part, parts may be manufactured without discarding potentially usable powder.

[0014] Powder reuse can relate to leftover powder from the additive manufacturing of a part. For example, if powder is withdrawn from a powder storage container or vessel for use in an additive manufacturing process, either the powder remaining in the powder storage container and / or the powder withdrawn from the powder storage container and potentially exposed to aspects of the additive manufacturing process can be reused in a future additive manufacturing process. The disclosed embodiments enable more efficient reuse of powder from previous additive manufacturing processes.

[0015] In certain embodiments, systems and methods for powder reuse may include powder characterization, powder modeling, inspection of one or more builds using the powder for additive manufacturing, and a determination of powder reuse. Powder characterization may include characterizing the original powder (e.g., a virgin powder lot) based on various aspects described below. Powder modeling may include computer modeling to determine the time when the powder is expected to be unsuitable for additive manufacturing (e.g., the future time when the powder is expected to be unsuitable for additive manufacturing). Powder modeling may include various computer models, such as a usage-based model, a chemistry-based model, or any combination thereof, as described below. The time determined by powder modeling may include the duration (e.g., minutes, hours, days, weeks, months, years) of powder use in the additive manufacturing process and / or future time independent of the duration. The time determined by powder modeling may also include the additive manufacturing process and / or the total number of parts additively manufactured using the powder. The time determined by powder modeling may also include the total time of various types of exposure of the powder, such as exposure to specific temperatures (e.g., temperatures above one or more threshold temperatures), exposure to additive manufacturing-related splashes, exposure to environmental conditions (e.g., ambient air, humidity, heat, etc.), or any combination thereof. Inspection may include one or more inspections of a part made using the powder at the time determined by powder modeling. If all inspections pass, the systems and methods may determine that the powder may be used indefinitely and / or a future inspection may optionally be scheduled for another future time. If one or more inspections fail, the systems and methods may determine that the powder has limited reuse and / or requires extended inspection. Inspection may include dimensional inspection, hardness inspection, impact testing, fracture toughness testing, creep testing, fatigue testing, non-destructive testing (NDT), tensile testing, ductility testing, corrosion testing (e.g., salt spray testing), oxidation testing, thermal testing, and / or other material or part inspections to verify satisfactory performance of the additively manufactured part. Each of the above-described aspects of the system and method for recycling powder may be used in the techniques described in detail below with reference to FIGS.

[0016] Turning now to the drawings and initially referring to Figure 1, a block diagram of one embodiment of an electrical power production system 100 is illustrated. It should be noted that the present disclosure may relate to any machine, and the electrical power production system 100 described herein is not intended to limit the scope of application of the present disclosure. Indeed, sintered machine parts may be additively manufactured via recycled powder for any type of machine, and the electrical power production system 100 is presented only as an example.

[0017] The power production system 100 includes a gas turbine system 102, a monitoring and control system 104, and a fuel supply system 106. The gas turbine system 102 may include a compressor 108, a combustion system 110, a fuel nozzle 112, a gas turbine 114, and an exhaust section 118. During operation, the gas turbine system 102 may draw air 120 into the compressor 108, which may then compress the air 120 and transfer the air 120 to the combustion system 110 (which may include, for example, multiple combustors). In the combustion system 110, the fuel nozzle 112 (or multiple fuel nozzles 112) may atomize fuel that mixes with the compressed air 120 to create, for example, an air-fuel mixture.

[0018] The mixture may be combusted in the combustion system 110 to generate hot combustion gases, which flow downstream to a turbine 114 to drive one or more turbine stages. For example, the combustion gases may travel through the turbine 114 to drive one or more stages of turbine blades 121, which in turn may drive the rotation of a shaft system 122. The shaft system 122 may further couple to one or more compressor stages having compressor blades 123. The shaft 122 may further connect to a load 124, such as a generator that uses the torque of the shaft 122 to generate electricity. After passing through the turbine 114, the hot combustion gases may be discharged to the environment via an exhaust section 118 as exhaust gases 126. The exhaust gases 126 may contain carbon dioxide (CO), carbon monoxide (CO), nitrogen oxides (NO), and other pollutants. x). Exhaust section 118 may include one or more exhaust treatment systems configured to reduce undesirable exhaust emissions.

[0019] The exhaust gas 126 may contain thermal energy, which may be recovered by a heat recovery steam generator (HRSG) 128. The HRSG 128 may include multiple heat exchangers, superheaters, economizers, and other equipment configured to extract thermal energy and generate steam. In a combined cycle system, such as the power plant 100, the hot exhaust gas 126 may flow from the gas turbine 114 to the HRSG 128, where it may be used to generate steam at one or more temperatures and pressures (e.g., low-pressure steam, intermediate-pressure steam, high-pressure steam). The steam generated in the HRSG 128 may then be passed through a steam turbine engine for further power generation. Additionally, the generated steam may be supplied to any other process where steam may be used, such as a gasifier used to gasify a feedstock to generate raw syngas. The production cycle of a gas turbine engine is often referred to as the "topping cycle," and the production cycle of a steam turbine engine is often referred to as the "bottoming cycle." Combining these two cycles may result in higher efficiency in both cycles. In particular, waste heat from the topping cycle can be captured and used to generate steam for use in the bottoming cycle.

[0020] In certain embodiments, system 100 may also include a controller 130 (e.g., an electronic and / or processor-based controller). Controller 130 may be communicatively coupled to a number of sensors 132, a human-machine interface (HMI) operator interface 134, and one or more actuators 136 suitable for controlling components of system 100. Actuators 136 may include valves, switches, positioners, pumps, etc. suitable for controlling various components of system 100. Controller 130 may receive data from sensors 132 and may be used to control compressor 108, combustor 110, turbine 114, exhaust section 118, load 124, HRSG 128, etc.

[0021] In particular embodiments, the HMI operator interface 134 may be executable by one or more computer systems of the system 100. A plant operator may interface with the industrial system 100 via the HMI operator interface 134. Accordingly, the HMI operator interface 134 may include various input / output devices (e.g., a mouse, keyboard, monitor, touch screen, or other suitable input / output devices) so that the plant operator may provide commands (e.g., control commands and / or operation commands) to the controller 130.

[0022] The controller 130 may include processor(s) 140 (e.g., microprocessor(s)) that may execute software programs to perform the disclosed techniques. Additionally, the processor 140 may include multiple microprocessors, one or more “general-purpose” microprocessors, one or more special-purpose microprocessors, and / or one or more application-specific integrated circuits (ASICS), or a combination thereof. For example, the processor 140 may include one or more reduced instruction set (RISC) processors. The controller 130 may include a memory device 142 that may store information such as control software, look-up tables, configuration data, etc. The memory device 142 may include a tangible, non-transitory, machine-readable medium, such as volatile memory (e.g., random access memory (RAM)) and / or non-volatile memory (e.g., read-only memory (ROM), flash memory, a hard drive, or any other suitable optical, magnetic, or solid-state storage medium, or a combination thereof). As previously mentioned, all systems, parts, components, etc. of the power production system 100 may have mechanical components or parts. The techniques described herein provide for sintering mechanical components or parts by recycling powder, such as using an additive manufacturing or sintering system 200 shown in FIG.

[0023] FIG. 2 is a block diagram of one embodiment of an additive manufacturing or sintering system 200 having a controller 202 (e.g., an additive manufacturing controller or sintering controller) operably coupled to an energy source 204 (e.g., a laser source). In certain embodiments, the sintering system 200 may be programmed and / or configured as a powder recycling system (PRS) that reuses powder for additively manufacturing (e.g., sintering) various parts. The controller 202 may include one or more processors 206 and a memory 208. The processor(s) 206 may execute computer instructions or code stored in the memory 208, such as code used to operate the energy source 204. The sintering system 200 also includes one or more powder source containers 210 (e.g., 210A, 210B, 210C, and 210D) that may be used to provide deposition powder 212 onto a movable build plate 213 included in a build chamber 214. As described below, the powder source containers 210A, 210B, 210C, and 210D may store or contain batches or quantities of new virgin powder, previously unused powder 212 having a first condition, previously unused powder 212 having a second condition, and a mixture or combination of new virgin powder and previously unused powder 212, respectively. The sintering system 200 may be configured to selectively use one or more of these powders in the powder source containers 210A, 210B, 210C, and 210D to additively manufacture a part. Conveying devices, such as rollers, pumps, and push actuators, can move and deposit the powder onto the build plate 213 as deposited powder 212. The build plate 213 may move up and down (e.g., along the z-axis) and sometimes along the x-axis or y-axis during printing.

[0024] After or once the powder is properly positioned as deposited powder 212, an energy source 204 may be applied to the deposited powder 212 (e.g., via a laser). The energy source 204 may be directed via a computer numerical control (CNC), such as by reading a file stored in a memory 208 that stores shape data for the part to be manufactured. While the shape of a particular layer to be sintered / bonded may be formed by the area to which the manufacturing system applies energy, certain properties of the part may be determined by the amount of energy directed to a particular area of ​​the powder 212. For example, in a general sense, greater flow (e.g., greater energy) provided by the laser beam / electron beam may result in more sintering / bonding of the powder and greater hardness, while less energy directed by the system results in more structural flexibility in the part.

[0025] The build chamber 214 may enclose a relatively inert environment (e.g., an inert gas chamber such as a nitrogen chamber) to aid in the desired bonding of the powder to the solid surface. One or more sensors 216 may be positioned in the build chamber 214, for example, to measure temperature, detect chemical levels (e.g., oxygen levels, nitrogen levels), detect spatter (e.g., via optical sensors), detect applied laser energy, measure humidity, etc. Once the energy source 204 forms a first solid layer, additional solid layers may be formed by adding additional powder 212 and / or lowering the first layer within the build chamber 214 until a complete part is 3D printed. It should be understood that the illustrated sintering system 200 may be a direct metal laser sintering (DMLS) system, a direct metal laser melting (DMLM) system, a selective laser sintering (SLS) system, an electron beam melting (EBM) system, or any other suitable additive manufacturing process that uses powder.

[0026] Unused powder 212, for example, excess or surplus unsintered powder 212 remaining in the build chamber 214 after a part has been fabricated, may typically be disposed of in a waste container 218. Unused powder 212 is generally an excess or surplus portion of a powder batch or powder quantity available for the sintering process; however, the unused powder 212 is not sintered as part of the sintering process. Nevertheless, the unused powder 212 may be exposed to various conditions, such as environmental conditions (e.g., ambient air, humidity, heat, etc.) and / or operating conditions (e.g., heat, splashing, etc.) associated with the sintering procedure. Before recycling the unused powder 212, the unused powder 212 may be processed to remove one or more impurities and / or contaminants, such as filtration to remove large particles, clumps, or splashes; moisture removal or dehydration to remove undesirable moisture; chemical treatment to remove chemical impurities; or any combination thereof. The techniques described herein may therefore enable the recycling of powder 212 in a more efficient and reliable manner. In the illustrated embodiment, a powder reclamation system (PRS) 220 may enable the reclamation of powder that would otherwise be disposed of after the manufacture of a part. The PRS 220 may include one or more computer models, such as a usage-based model 222 and / or a chemistry-based model 224. In one example of use, the PRS 220 may receive as input a "characterization" of unused or virgin powder. Characterization may include determining the type of powder material (e.g., type of metal, ceramic, cermet, polymer, etc.), chemical or material composition, material properties of the powder (e.g., hardness, corrosion resistance, oxidation resistance, wear resistance, coefficient of friction, heat resistance, electrical conductivity, etc.), powder particle size (e.g., mean or median diameter of powder particles per measured value or manufacturing specifications), particle size distribution (e.g., normal distribution or bell curve of powder particle diameters per measured value or manufacturing specifications), powder particle uniformity (e.g., diameter uniformity, chemical or material composition, material properties, etc.), manufacturing date of the powder, manufacturing specifications of the powder, powder measurement or inspection data, percentage of impurities in the powder (e.g., percentage of undesired material), etc. Powder measurements and inspections (e.g., mechanical testing, chemical testing, etc.) may also be used to aid in powder characterization.The PRS 220 may be a stand-alone system communicatively coupled to the sensor 216 or may be part of the controller 202. The PRS 220 may be a software system or computer program, a hardware device, or a combination thereof.

[0027] Prior to or during additive manufacturing of a part, the models 222, 224 may be used to determine (e.g., derive, calculate, estimate, or predict) the remaining lifespan of the powder, including recycled powder that may be redeposited on the build bed 213. The remaining lifespan may correspond to the time when the powder (e.g., recycled powder) is expected to no longer be suitable for use in an additive manufacturing process. The models 222, 224 may determine this time (e.g., remaining lifespan) as a duration (e.g., minutes, hours, days, weeks, months, years) of the powder's use in the additive manufacturing process, a future time independent of a time period (e.g., a future date and time), a total number of additive manufacturing processes and / or parts to be additively manufactured using the powder, or any combination thereof.

[0028] The usage-based model(s) 222 may use as inputs the total powder used by the sintering system 200, the total powder used to print the next part, the height of the next build(s), the powder environment (storage environment and / or build chamber 214 environment sensed via sensors 216), the density of the build plate 213, the powder recycling technique (e.g., new powder added from above, new powder added from below, a blend of new and recycled powder), or a combination thereof, to determine the remaining time and / or number of remaining builds that the powder can be recycled. In certain embodiments, the usage-based model(s) 222 may be created using machine learning (ML) techniques.

[0029] For example, data recording multiple part builds using a particular powder (e.g., a characterized powder) may be collected along with inspections performed on the resulting parts. The inspections may include x-rays, ultrasound, chemical tests, etc., detailing how viable the built part was based on the powder (e.g., recycled powder, a mixture of recycled and new powder, etc.). That is, an inspection regime may be configured to collect data to determine how well a particular part prints when powder is reused multiple times based on first-in, last-out (FILO) addition of new powder to recycled powder, first-in, first-out (FIFO) addition of new powder, or a mixture of new and recycled powder. The results may be used to train a machine learning system, such as a system using neural networks, state vector machines, data mining, etc. The trained system (e.g., PRS220) can then derive, for a given use case, the time until the powder is no longer in a desired state or the number of builds of a particular part that the powder can be used for. The output may also include the risks associated with using recycled powder or the time at which it may be desirable to inspect the feasibility of printed parts to determine if the recycled powder is still viable.

[0030] The chemistry-based model(s) 224 may use chemistry-based methods or simulations that may use time or build counts as inputs to create chemical equations that model the effects of oxygen, nitrogen, evaporation, temperature, age, humidity, or a combination thereof. The chemistry-based model 224 may then output the time when the recycled powder is no longer viable, the risks associated with using the recycled powder (e.g., feasibility risk), or the time when it may be desirable to inspect the feasibility of the printed part. Thus, the powder 212 can be continuously reused, resulting in efficient manufacturing with less (or in some cases, no) powder waste.

[0031] The controller 202 and / or PRS 220 are configured to schedule one or more inspections of a part additively manufactured using recycled powder using a time determined by the PRS 220 (e.g., the remaining life of the powder). At this determined time, the additively manufactured part may undergo various tests to determine whether the additively manufactured part meets various inspection criteria. If all inspections pass, the controller 202 and / or PRS 220 may determine that the powder may be used indefinitely and / or a future inspection may optionally be scheduled for another future time. If one or more inspections fail, the controller 202 and / or PRS 220 may determine that the powder has a reuse limit and / or that the powder requires extended inspection. The inspections may include dimensional inspection, hardness inspection, impact testing, fracture toughness testing, creep testing, fatigue testing, non-destructive testing (NDT), tensile testing, ductility testing, corrosion testing (e.g., salt spray testing), oxidation testing, thermal testing, and / or other material or part inspections to verify satisfactory performance of the additively manufactured part. In certain embodiments, if all inspections for the additively manufactured part pass at a determined time (e.g., the initially determined remaining life of the powder), no further inspections may be necessary, and the powder may continue to be reused in future additive manufacturing processes without any time restrictions. In certain embodiments, even if the aforementioned techniques may determine infinite reuse of the powder, the controller 202 and / or PRS 220 may optionally schedule one or more future inspections to re-inspect the powder for future reuse.

[0032] In certain embodiments, the sintering system 200 (e.g., PRS) is configured to additively manufacture or build one or more mechanical parts using machine learning techniques by selectively using new virgin powder 212 (e.g., excess unsintered powder) based on a first criterion, by selectively using virgin powder 212 (e.g., excess unsintered powder) based on a second criterion, and by selectively using a combination or mixture of new virgin powder and virgin powder 212 based on a third criterion. The criteria may include levels of importance for various parts and regions of the part, and the importance levels may include a scaled range of 1 to 5, 1 to 10, 1 to 100, or any suitable range. A high number in the scaled range may indicate the need to use new virgin powder. A low number in the scaled range may indicate the possibility of using virgin powder 212. A mid-range number in the scaled range may indicate the possibility of using a mixture or combination of new virgin powder and virgin powder 212. The criteria may also include location criteria, such as locations exposed to a fluid flow path (e.g., exhaust gas flow path, combustion chamber area, compressed air flow path, etc.) or locations not exposed to a fluid flow path. The criteria may also include other operating parameters, such as expected thermal stress, expected exposure to corrosion, erosion, or other degradation, expected mechanical stress, or any combination thereof. Each of the foregoing criteria and others may be used to identify parts and regions suitable for additive manufacturing using new virgin powder, virgin powder 212, or a combination or mixture of new virgin powder and virgin powder 212.

[0033] In certain embodiments, sintering system 200 may be configured to selectively use one or more of fresh virgin powder from powder source container 210A, previously virgin powder 212 having a first condition from powder source container 210B, previously virgin powder 212 having a second condition from powder source container 210C, and a mixture of fresh virgin powder and previously virgin powder 212 from powder source container 210D to additively manufacture a part. For example, sintering system 200 may be programmed or configured to selectively use fresh virgin powder from powder source container 210A to additively manufacture an entire part and / or specific regions of a part having relatively high or critical functionality, such as turbine blades and vanes, compressor blades and vanes, fuel nozzles, and / or surfaces exposed to a fluid flow path. By way of further example, the sintering system 200 may be programmed or configured to selectively use virgin powder 212 from the powder source containers 210B and 210C to additively manufacture an entire part and / or specific regions of the part having relatively less critical or non-critical functions, such as seal supports, regions outside of fluid flow paths, legs, feet, support structures, etc. For example, virgin powder 212 having a first condition may be of higher quality for additively manufacturing a part than virgin powder 212 having a second condition, and thus the quality level of the virgin powder 212 may also be a basis for how and where to use the virgin powder 212. The first and second conditions may correspond to conditions determined by inspecting the virgin powder 212, the total number of sintering procedures performed with a quantity of powder that previously includes virgin powder 212, the total time that the powder including the previously unused powder 212 was exposed to the environmental and / or operating conditions of the sintering procedure, or any combination thereof. The sintering system 200 may be programmed or configured to use the lowest quality virgin powder 212 for the least critical or least important parts or surfaces, and the sintering system 200 may progressively use higher quality virgin powder 212 for the more critical parts or surfaces.If the virgin powder 212 alone is not of sufficient quality, the sintering system 200 can be programmed or configured to selectively use a mixture of fresh virgin powder 212 and previously virgin powder from the powder source container 210D to additively manufacture entire parts and / or specific regions of parts that are of relatively intermediate importance, e.g., less important than parts and surfaces made with fresh virgin powder, but more important than parts and surfaces made with virgin powder 212 alone. Thus, the sintering system 200 can be programmed or configured to use powder based on various conditions and qualities of the powder, various importance of the part and / or surface to be additively manufactured, based on user input, based on computer models, and based on machine learning (ML) techniques.

[0034] For example, the computer model and / or machine learning techniques may determine when and where to use new virgin powder to improve the quality or integrity of additively manufactured parts and surfaces, and when and where to use previously unused powder 212 and / or mixtures of new virgin powder and previously unused powder 212 to reduce powder waste and lower manufacturing costs as appropriate for less critical parts and surfaces. The computer model and / or machine learning techniques may use inspection and / or operational data related to additively manufactured parts to help improve the selection and use of new virgin powder, unused powder 212, and mixtures thereof for various parts and surfaces.

[0035] The computer model and / or machine learning techniques may also be configured to determine how to mix or generally combine new virgin powder with previously unused powder 212 to reduce powder waste, reduce manufacturing costs, and ensure the use of the previously unused powder 212 before it is no longer viable for use in the sintering procedure. For example, for one or more sintering procedures, the computer model and / or machine learning techniques may place new virgin powder at the bottom of the powder source container 210D while placing new virgin powder 212 at the top of the powder source container 210D, such that the sintering procedure by the sintering system 200 uses all of the previously unused powder 212 before using the new virgin powder to manufacture one or more parts or surfaces. By way of further example, for one or more sintering procedures, the computer model and / or machine learning techniques may place new virgin powder at the top of the powder source container 210D while placing previously unused powder 212 at the bottom of the powder source container 210D, such that the new virgin powder at the top provides some protection against additional exposure to the previously unused powder 212 before or during the sintering procedure with the sintering system 200.

[0036] Further, in certain embodiments, the computer model and / or machine learning techniques may be configured to improve the operation of the sintering system 200, such that the time and type of exposure to the virgin powder 212 is substantially reduced or minimized, improving the quality and usability of the virgin powder 212 for future sintering procedures. The exposure may include environmental exposure (e.g., exposure to ambient air, heat, humidity, etc.), operational exposure (e.g., operational heat, splashing, etc. during the sintering procedure), or a combination thereof. For example, the sintering system 200 may control the laser to perform the sintering procedure in a manner that reduces heat exposure or heat transfer to the virgin powder 212, the sintering system 200 may control the sintering procedure to reduce splashing to the virgin powder 212, the sintering system 200 may shorten the total time of the sintering procedure to reduce various exposures to the virgin powder 212, or any combination thereof. Furthermore, the sintering system 200 may include one or more shields (e.g., heat shield, splash shield, environmental shield) to protect the virgin powder 212 before, during, and after the sintering procedure. In some embodiments, the sintering system 200 may be configured to selectively move one or more shields for better positioning to protect the unused powder 212 before, during, and after the sintering procedure.

[0037] 3 is a flowchart of one embodiment of a process 300 suitable for reusing powders, such as powder 212. Process 300 may be implemented, for example, as computer code or instructions stored in memory 208 and executable by processor(s) 206. In the illustrated embodiment, process 300 may first characterize (block 302) the powder to be used for sintering. As previously mentioned, characterization may include determining the type of powder (e.g., metal powder, ceramic powder, cermet powder, polymer powder, etc.), chemical composition, powder particle size, measuring the median or mean uniformity of the powder particles, determining the date of manufacture of the powder, etc. Powder testing (e.g., mechanical testing, chemical testing) may also be used to characterize (block 302) the powder (e.g., new powder).

[0038] Process 300 can then receive build inputs (block 304) such as the next build and build file (e.g., shape files used to create one or more parts for a given build), so that process 300 can know or estimate the amount of powder to be used, the height(s) of the next build, the powder environment (storage environment sensed via sensors 216 and / or the environment of build chamber 214), the density of build plate 213, the powder reuse technique (e.g., new powder added from above, new powder added from below, blending new powder with recycled powder), etc. Process 300 can then determine (block 306) certain modeled outputs such as the remaining time the powder can be reused, the remaining number of builds the powder can be reused, the risk that the part is a viable part, the time to start checking the part for feasibility, the estimated or predicted time to stop using powder, or a combination thereof. When deriving the time to start the inspection, the process 300 can benefit from inspecting the feasibility of the part, since it can derive the time until the part starts to become no longer feasible based on the output of the models 222, 224.

[0039] Modeled outputs, such as the remaining time the remaining powder can be used, the remaining number of builds the powder can be reused, the risks associated with using the reused powder, the time it may be desirable to inspect the quality and / or condition of the powder (e.g., previously unused powder 212 is used in subsequent additive manufacturing of a part), and / or the time it may be desirable to inspect the feasibility of a printed part, or combinations thereof, may be derived by either or both of models 222, 224. That is, the data received from block 304 may be provided as input to models 222, 224 to derive (block 306) the remaining number of builds the powder can be reused, the risks associated with using the reused powder, the time it may be desirable to inspect the feasibility of a printed part, or combinations thereof.

[0040] Process 300 may then build one or more parts (block 308). That is, process 300 may 3D print one or more additional parts via the sintering system while sensing data via sensors 216. Indeed, in some embodiments, process 300 may then return to block 304 and continue with the new input (or sensed data), e.g., to sense more data via sensors 216 or to receive other input for the next build(s). Thus, powder recycling may minimize or even eliminate powder waste after building.

[0041] In certain embodiments, process 300 may characterize the powder material (block 302) and input the powder characterization into one or more models (e.g., a usage-based model, a chemistry-based model, etc.) to generate a calculated number of builds and future inspection time (block 306). As described above, the future inspection time may correspond to the remaining useful life for reuse of the powder, which may be based on calculations, estimates, predictions, etc. Process 300 may then perform a build according to the number of builds and future inspection time (block 308). If process 300 determines that several critical tests fail the inspection build, process 300 may determine that the powder has limited use and requires extended inspection. If process 300 determines that all tests pass the inspection build, process 300 may determine that the powder can be used indefinitely.

[0042] Examples are used herein to disclose the invention, including the best mode, and to enable any person skilled in the art to practice the invention, including making and using any devices or systems, and performing any methods incorporated therein. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

[0043] The technical effect may include deriving the time until powder used in the sintering system can be reused via a model, such as a usage-based model and / or a chemistry-based model. The powder may be characterized. The usage-based model may take one or more inputs, such as a first total sintered powder used by the sintering system to fill the sintering system, a second total sintered powder used to print the next part, the height of the first machine part, the sintered powder environment, the density of the build plate included in the sintering system, a powder reuse strategy including adding new powder from the top of the sintering system, adding new powder from the bottom of the sintering system, blending new virgin powder with excess unsintered powder, or a combination thereof. The chemistry-based model(s) may take input measurements obtained from one or more sensors included in the sintering system.

[0044] The subject matter detailed above may be governed by one or more of the provisions set forth below.

[0045] A system comprising: a powder reuse system (PRS) executable via a processor; configured to receive one or more inputs for building a first mechanical part in a sintering system; retrieve a model configured to model reuse of sintered powder; and apply the one or more inputs to the model to derive a time at which excess unsintered powder remaining after printing the mechanical part through the sintering system using the sintered powder can be reused to build a second mechanical part.

[0046] The system of the preceding clause, wherein the time includes at least one of a duration of use of the excess unsintered powder during an additive manufacturing process, a future time independent of the duration, a total number of additive manufacturing processes and / or additively manufactured parts that are produced using the sintered powder and leave the excess unsintered powder, or a total time of various types of exposure of the excess unsintered powder.

[0047] The system of any of the preceding clauses, wherein the one or more inputs include a characterization of the sintered powder.

[0048] The system of any of the preceding clauses, wherein the characterization includes the metal type of the sintered powder, the chemical composition of the sintered powder, the grain size of the sintered powder, the grain uniformity of the sintered powder, the manufacturing date of the sintered powder, or a combination thereof.

[0049] The system of any of the preceding clauses, wherein the model includes a usage-based model, and the one or more inputs include a first total sintered powder used by the sintering system to fill the sintering system, a second total sintered powder used to print the next part, a height of the first machine part, a sintered powder environment, a density of a build plate included in the sintering system, and a powder recycling technique including adding new powder from the top of the sintering system, adding new powder from the bottom of the sintering system, blending new virgin powder with excess unsintered powder, or a combination thereof.

[0050] 10. The system of claim 1, wherein the usage-based model includes a machine learning (ML) model trained by using the inspection part data and a sintering log including values ​​of one or more inputs obtained during printing of a plurality of inspection parts.

[0051] The system of any preceding clause, wherein the model includes a chemistry-based model and the one or more inputs include measurements obtained from one or more sensors included in the sintering system.

[0052] The system of any of the preceding clauses, wherein the measurements include oxygen level, nitrogen level, fugitive count, temperature, humidity, or a combination thereof.

[0053] The system of any of the preceding clauses, wherein the PRS is configured to build the second machine part by using machine learning techniques to selectively use new virgin powder based on a first criterion and selectively use surplus unsintered powder based on a second criterion.

[0054] The system of any of the preceding clauses, wherein the PRS is configured to derive, via the model, a build count of one or more machine parts using excess green powder in the sintering system, a feasibility risk of building a second machine part in the sintering system using excess green powder, an inspection time for inspecting the feasibility of the second machine part, or a combination thereof.

[0055] The system of any of the preceding clauses, wherein the PRS is configured to search for a second model configured to model reuse of the sintered powder and derive the time via the model, the second model, or a combination thereof, wherein the model includes a usage-based model and the second model includes a chemistry-based model.

[0056] A method for manufacturing a mechanical part, comprising: receiving, via a powder recycling system (PRS), one or more inputs for building a first mechanical part in a sintering system; retrieving a model configured to model the recycling of sintered powder; and applying the one or more inputs to the model to derive a time during which excess unsintered powder remaining after printing the mechanical part via the sintering system using the sintered powder can be recycled to build a second mechanical part.

[0057] The method of any preceding clause, wherein the one or more inputs include a characterization of the sintered powder, the characterization including a metal type of the sintered powder, a chemical composition of the sintered powder, a grain size of the sintered powder, a grain uniformity of the sintered powder, a manufacturing date of the sintered powder, or a combination thereof.

[0058] The method of any of the preceding clauses, wherein the model includes a usage-based model, and the one or more inputs include a first total sintered powder used by the sintering system to fill the sintering system, a second total sintered powder used to print the next part, a height of the first machine part, a sintered powder environment, a density of a build plate included in the sintering system, and a powder recycling technique including adding new powder from the top of the sintering system, adding new powder from the bottom of the sintering system, blending new virgin powder with excess unsintered powder, or a combination thereof.

[0059] The method of any preceding clause, wherein the usage-based model includes a machine learning (ML) model trained by using the inspection part data and a sintering log including values ​​of one or more inputs obtained during printing of a plurality of inspection parts.

[0060] 10. The method of any of the preceding clauses, wherein the model includes a chemistry-based model and the one or more inputs include measurements obtained from one or more sensors included in the sintering system.

[0061] The method of any of the preceding clauses, including deriving, via the model, the number of builds of one or more machine parts using excess green powder in the sintering system, the feasibility risk of building a second machine part in the sintering system using excess green powder, the inspection time for inspecting the feasibility of the second machine part, or a combination thereof.

[0062] A non-transitory computer-readable medium comprising instructions that, when executed, cause a processor to receive, via a powder reuse system (PRS), one or more inputs for building a first mechanical part in a sintering system; retrieve, via the PRS, a model configured to model the reuse of sintered powder; and derive, via the PRS, a time during which excess unsintered powder remaining after printing the mechanical part through the sintering system using the sintered powder can be reused to build a second mechanical part by applying the one or more inputs to the model.

[0063] The computer-readable medium of any preceding clause, wherein the one or more inputs include a characteristic evaluation of the sintered powder, the characteristic evaluation including a metal type of the sintered powder, a chemical composition of the sintered powder, a grain size of the sintered powder, a grain uniformity of the sintered powder, a manufacturing date of the sintered powder, or a combination thereof.

[0064] The computer-readable medium of any of the preceding clauses, wherein the model includes a usage-based model, and the one or more inputs include a first total sintered powder used by the sintering system to fill the sintering system, a second total sintered powder used to print the next part, a height of the first machine part, an environment for the sintered powder, a density of a build plate included in the sintering system, and a powder recycling technique including adding new powder from the top of the sintering system, adding new powder from the bottom of the sintering system, blending new virgin powder with excess unsintered powder, or a combination thereof.

[0065] 10. The computer-readable medium of any preceding clause, wherein the model includes a chemistry-based model and the one or more inputs include measurements obtained from one or more sensors included in the sintering system.

[0066] A computer-readable medium as described in any of the preceding clauses, comprising instructions that, when executed, cause a processor to derive, via the model, the number of builds of one or more machine parts using excess green powder in a sintering system, the feasibility risk of building a second machine part in a sintering system using excess green powder, an inspection time for inspecting the feasibility of the second machine part, or a combination thereof. [Explanation of symbols]

[0067] 100 Electricity production systems, power plants 102 Gas Turbine System 104 Monitoring and Control Systems 106 Fuel Supply System 108 Compressor 110 Combustion systems, combustors 112 Fuel nozzle 114 Turbine 118 Exhaust Section 120 Air 121 Turbine Blade 122 Shaft system, shaft 123 Compressor Blade 124 Load 126 Exhaust gas, high temperature exhaust 128 Heat Recovery Steam Generator 130 Controller 132 sensors 134 Human Machine Interface (HMI) Operator Interface 136 Actuator 140 processors 142 Memory Devices 200 Sintering System 202 Controller 204 Energy Sources 206 processors 208 memory 210 Powder Source Container 210A powder source container 210B Powder Source Container 210C powder source container 210D powder source container 212 Powder 213 Modeling plate, modeling bed 214 Build Chamber 216 Sensors 218 Container 220 Powder Reuse System (PRS) 222 Used Base Model 224 Chemistry-Based Model

Claims

1. 1. A system comprising: a powder recycling system (PRS) (220) executable via a processor (140); receiving one or more inputs for building a first machine part in a sintering system (200); Find a model configured to model the reuse of sintered powder; Applying the one or more inputs to the model to derive a time during which excess unsintered powder remaining after printing the mechanical part via the sintering system (200) using the sintered powder can be reused to build a second mechanical part. The system is configured as follows.

2. 2. The system of claim 1, wherein the time includes at least one of a duration of use of the excess green powder during an additive manufacturing process, a future time independent of the duration, a total number of additive manufacturing processes and / or additively manufactured parts made using the sintered powder that leave the excess green powder, or a total time of various types of exposure of the excess green powder.

3. 2. The system of claim 1, wherein the one or more inputs include a characteristic evaluation of the sintered powder, the characteristic evaluation including a metal type of the sintered powder, a chemical composition of the sintered powder, a grain size of the sintered powder, a grain uniformity of the sintered powder, a manufacturing date of the sintered powder, or a combination thereof.

4. 2. The system of claim 1, wherein the model includes a usage-based model (222), and the one or more inputs include a first total sintered powder used by the sintering system (200) to fill the sintering system (200), a second total sintered powder used to print a next part, a height of a first machine part, an environment for the sintered powder, a density of a build plate included in the sintering system (200), and a powder recycling strategy including adding new powder from the top of the sintering system (200), adding new powder from the bottom of the sintering system (200), blending new virgin powder with the excess unsintered powder, or a combination thereof.

5. 5. The system of claim 4, wherein the usage-based model (222) comprises a machine learning (ML) model trained by using inspection part data and a sintering log including the values ​​of the one or more inputs obtained during printing of a plurality of inspection parts.

6. 2. The system of claim 1, wherein the model comprises a chemically based model (224), and the one or more inputs comprise measurements obtained from one or more sensors (216) included in the sintering system (200), the measurements comprising oxygen level, nitrogen level, fugitive count, temperature, humidity, or a combination thereof.

7. 10. The system of claim 1, wherein the PRS is configured to use machine learning techniques to build the second machine part by selectively using new virgin powder based on a first criterion, by selectively using the excess green powder based on a second criterion, and by selectively using a combination or mixture of the new virgin powder and the excess green powder based on a third criterion.

8. 2. The system of claim 1, wherein the PRS (220) is configured to derive, via the model, the number of builds of one or more machine parts using the excess green powder in the sintering system (200), the feasibility risk of building the second machine part in the sintering system (200) using the excess green powder, the inspection time for inspecting the feasibility of the second machine part, or a combination thereof.

9. 2. The system of claim 1, wherein the PRS (220) is configured to search for a second model configured to model the recycling of the sintered powder and derive the time via the model, the second model, or a combination thereof, the model comprising a usage-based model (222) and the second model comprising a chemistry-based model (224).

10. 1. A method for manufacturing a machine part, comprising: receiving, via a powder recycling system (PRS) (220), one or more inputs for building a first machine part in a sintering system (200); Retrieving, via the PRS (220), a model configured to model the recycling of sintered powder; applying the one or more inputs to the model via the PRS (220) to derive a time during which excess unsintered powder remaining after printing the mechanical part via the sintering system (200) using the sintered powder can be reused to build a second mechanical part; A method for manufacturing a machine part, comprising:

11. 11. The method of claim 10, wherein one or more inputs include a characterization of the sintered powder, the characterization including a metal type of the sintered powder, a chemical composition of the sintered powder, a grain size of the sintered powder, a grain uniformity of the sintered powder, a manufacturing date of the sintered powder, or a combination thereof.

12. 11. The method of claim 10, wherein the model includes a usage-based model (222), and the one or more inputs include a first total sintered powder used by the sintering system (200) to fill the sintering system (200), a second total sintered powder used to print a next part, a height of a first machine part, an environment for the sintered powder, a density of a build plate included in the sintering system (200), a powder recycling strategy including adding new powder from the top of the sintering system (200), adding new powder from the bottom of the sintering system (200), blending new virgin powder with the excess unsintered powder, or a combination thereof.

13. 13. The method of claim 12, wherein the usage-based model (222) comprises a machine learning (ML) model trained by using inspection part data and a sintering log including the values ​​of the one or more inputs obtained during printing of a plurality of inspection parts.

14. The method of claim 10, wherein the model comprises a chemically based model (224) and the one or more inputs comprise measurements obtained from one or more sensors (216) included in the sintering system (200).

15. 11. The method of claim 10, further comprising deriving, via the model, the number of builds of one or more machine parts using the excess green powder in the sintering system (200), the feasibility risk of building the second machine part in the sintering system (200) using the excess green powder, the inspection time for inspecting the feasibility of the second machine part, or a combination thereof.

16. 1. A non-transitory computer-readable medium, comprising: When executed, the processor (140) receiving, via a powder recycling system (PRS) (220), one or more inputs for building a first machine part in a sintering system (200); retrieving, via said PRS (220), a model configured to model the recycling of sintered powder; Applying the one or more inputs to the model via the PRS (220) derives a time during which excess unsintered powder remaining after printing the mechanical part via the sintering system (200) using the sintered powder can be reused to build a second mechanical part. A non-transitory computer-readable medium containing instructions.

17. 17. The computer-readable medium of claim 16, wherein the one or more inputs include a characterization of the sintered powder, the characterization including a metal type of the sintered powder, a chemical composition of the sintered powder, a grain size of the sintered powder, a grain uniformity of the sintered powder, a manufacturing date of the sintered powder, or a combination thereof.

18. 17. The computer-readable medium of claim 16, wherein the model includes a usage-based model (222), and the one or more inputs include a first total sintered powder used by the sintering system (200) to fill the sintering system (200), a second total sintered powder used to print a next part, a height of a first machine part, an environment of the sintered powder, a density of a build plate included in the sintering system (200), a powder recycling technique including adding new powder from the top of the sintering system (200), adding new powder from the bottom of the sintering system (200), blending new virgin powder with the excess unsintered powder, or a combination thereof.

19. 17. The computer-readable medium of claim 16, wherein the model comprises a chemically-based model (224) and the one or more inputs comprise measurements obtained from one or more sensors (216) included in the sintering system (200).

20. 17. The computer-readable medium of claim 16, comprising instructions that, when executed, cause the processor (140) to derive, via the model, a number of build times for one or more machine parts using the excess green powder in the sintering system (200), a feasibility risk for building the second machine part in the sintering system (200) using the excess green powder, an inspection time for inspecting the feasibility of the second machine part, or a combination thereof.

Images