Metal powder management system for additive manufacturing

Abstract

To provide a closed loop metal powder management method for additive manufacturing. A closed loop metal powder management method for additive manufacturing includes providing virgin metal powder to a closed powder container that includes at least one sensor, tracking device, or optical device. The metal powder is transferred to an additive manufacturing system, a portion of the layer of metal powder is solidified, and excess metal powder is transferred from the additive manufacturing system to a powder container, a second powder container, or an internal powder container. Virgin powder or a second metal powder is added to the excess metal powder, the quality of the composite powder is verified, and the process is repeated at least once, after which powder physical movement data relating to at least one of these steps is collected and stored in a data repository. Powder material parameters may be measured and evaluated, and the powder material parameters may be stored in the data repository.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 155,170, filed March 1, 2021, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] [background] Additive manufacturing generally relates to the process of producing 3D objects by building up layers of material or materials. Traditionally, the material may be fed to an additive manufacturing machine in the form of a powder (e.g., metal powder).

[0003] Powders have a range of physical and chemical properties that are known to be important for their processability, i.e., what makes a powder suitable or unsuitable for additive manufacturing. Some of these properties are intrinsic to the material itself, while others are influenced by the powder's surrounding environment. For example, powder properties can be affected by ambient humidity, reactive gases in the air, contaminants such as other powders or foreign objects, electrostatic forces, and other external factors. As the powder properties affect the properties of the additive manufactured article, it is important from a quality perspective to monitor and control such factors.

[0004] Furthermore, in additive manufacturing, powders may be reused (recycled) multiple times throughout the process, which can lead to detectable degradation or changes in material properties, which in turn can affect throughput and the final quality of the additively manufactured article.

[0005] [overview] Various embodiments of the invention include a closed loop system that allows a user to track metal powders from initial production to final use in an additively manufactured part. The system maintains the metal powders under a controlled atmosphere and maintains digitally documented quality control for detailed traceability, material genealogy, and risk management against contamination, excessive humidity, powder oxidation, and other undesirable events. Additionally, the system allows a user to add or combine used metal powders recycled from an additive manufacturing process to virgin (i.e. unused) metal powders and verify their quality, while maintaining the metal powders under a controlled or inert atmosphere with associated environmental monitoring and documented quality control that is traceable down to the identity of the batch and sub-batch of material.

[0006] An advantage of the system described herein is that metal powders managed within the system have a unique digital fingerprint that can be tied to any combination of physical movement history, environmental conditions, material property data, process history, and other factors, allowing users to make intelligent decisions on how to proceed, such as reusing the metal powder, scrapping the powder, retesting the powder, etc.

[0007] In one aspect, various embodiments of the invention relate to a closed loop metal powder management method for additive manufacturing. The method includes obtaining virgin metal powder suitable for additive manufacturing, the metal powder being disposed in a sealed powder container including at least one sensor, tracking device, and / or optical device. To perform the powder transfer in a closed loop, the powder container is connected to an additive manufacturing system with an automated metal powder transfer system. The automated metal powder transfer system is controllable by a pneumatic and / or electronic (e.g., programmable logic) controller and adapted to control the supply of metered amounts of the metal powder to the additive manufacturing system.

[0008] The metal powder from the powder container is fed to an additive manufacturing system. The additive manufacturing system is operated to form at least one layer of metal powder on a build plate of the additive manufacturing system. A portion of the at least one layer of metal powder is solidified and an excess portion of the layer of metal powder is left in powder form. These two steps are repeated at least once.

[0009] The excess metal powder is transferred from the additive manufacturing system to the powder container, the second powder container, or the internal powder container. Virgin metal powder is added to the excess metal powder in the powder container, the second powder container, or the internal powder container to form a composite powder. The quality of the composite powder is verified. The previous steps starting with connecting the metal powder to the additive manufacturing system are repeated at least once with the verified composite powder. Powder physical movement data associated with at least one of the above steps is collected and stored in a data repository. In each of these steps, the sensor, tracking device, and / or optical device are electronically accessible.

[0010] One or more of the following features may be included: the at least one sensor is adapted to measure at least one of oxygen in the powder container, a temperature in the powder container, humidity in the powder container, pressure in the powder container, a color of the powder in the powder container, a morphology of the powder in the powder container, a level of powder disposed in the powder container, a mass of powder disposed in the powder container, and / or a contamination of the powder disposed in the powder container.

[0011] The metal powder and excess metal powder may be maintained under an inert atmosphere during each of the steps.

[0012] At least one powder material parameter of the surplus metal powder may be measured.

[0013] The composite powder may be sieved before repeating the steps with the identified powder.

[0014] Prior to validation, the composite powders may be mixed.

[0015] Supplying the metal powder from the powder container to the additive manufacturing system may include supplying the metal powder to a powder storage repository within the additive manufacturing system, wherein an amount of the metal powder supplied is sufficient to form at least two layers of powder.

[0016] Solidifying at least a portion of the metal powder layer may include bonding, sintering, and / or melting.

[0017] Verifying the quality of the composite powder may include (i) measuring and evaluating at least one powder material parameter of the composite powder, and / or (ii) examining physical movement data of the powder.

[0018] At least one powder material parameter of the composite powder may be stored in a data repository.

[0019] The powder material parameters of the composite powder may be interstitial element chemistry, substitutional element chemistry, trace element analysis, apparent density, tapped density, particle size distribution, moisture, powder shape, powder morphology, Hall flow, Carney flow, sieve specification, trapped gas content, rheometric stability index, and / or angle of repose.

[0020] Measuring at least one powder material parameter of the composite powder may include capturing an optical image, capturing a scanning electron microscope image, capturing a cross-sectional image, performing a coulometric titration, and / or performing a pycnometry measurement.

[0021] The powder physical movement data may include powder storage data, an identification of the additive manufacturing system, the number of times the metal powder has been fed to the additive manufacturing system, and / or the number of times the powder has been mixed with virgin metal powder.

[0022] Process data relating to at least one of the steps may be collected and stored in a data repository. The process data may include a laser power during the solidification step, a speed of the laser during the solidification step, and / or a thickness of the formed layer. Verifying the quality of the composite powder may include examining the collected process data.

[0023] The sealed powder container may comprise a shipping powder container in which the virgin metal powder may be shipped after its production. Prior to carrying out the steps outlined above, the virgin metal powder may be transferred from the shipping powder container to the sealed powder container.

[0024] In another aspect, various embodiments of the present invention relate to a closed loop metal powder management method for additive manufacturing, comprising obtaining a first metal powder suitable for additive manufacturing, the first metal powder being disposed in a sealed powder container including at least one sensor, tracking device, or optical device. To perform the transfer of the metal powder in a closed loop, the powder container is connected to an additive manufacturing system with an automated metal powder transfer system. The automated metal powder transfer system is controllable by a programmable logic controller and adapted to control the supply of a programmed amount of the metal powder to the additive manufacturing system.

[0025] The metal powder is fed from a powder container to an additive manufacturing system. The additive manufacturing system is operated to form at least one layer of the metal powder on a build plate of the additive manufacturing system. A portion of the at least one layer of the metal powder is solidified and an excess portion of the metal powder layer is left in powder form. These two steps are repeated at least once.

[0026] The excess metal powder is transferred from the additive manufacturing system to an excess powder container that includes at least one excess metal powder container sensor, excess powder container tracking device, or excess powder container optical device. A second metal powder is added to the excess powder container to form a composite powder. The quality of the composite powder in the excess powder container is confirmed.

[0027] The previous steps beginning with connecting the metal powder to the additive manufacturing system with the verified composite powder disposed in the excess powder container are repeated at least once. Powder physical movement data associated with at least one of the above steps is collected and stored in a data repository. In each of the above steps, at least one of the at least one sensor, tracking device, optical device, excess powder container sensor, excess powder container tracker, and / or excess powder container optical device is electronically accessible.

[0028] One or more of the following features may be included: the first metal powder and the second metal powder may be of the same composition, e.g., they may be from a single batch; the first metal powder and the second metal powder may be from different batches; the first metal powder may be a virgin metal powder.

[0029] The at least one sensor may be adapted to measure at least one of oxygen in the powder container, temperature in the powder container, humidity in the powder container, pressure in the powder container, color of the powder in the powder container, morphology of the powder in the powder container, a level of powder disposed in the powder container, a mass of powder disposed in the powder container, and / or contamination of the powder disposed in the powder container.

[0030] The extra powder container may consist of an internal powder container or an external powder container.

[0031] During the above steps, the first metal powder, the second metal powder, the excess metal powder, and the composite powder may be maintained under an inert atmosphere.

[0032] At least one powder material parameter of the surplus metal powder can be measured.

[0033] The composite powder may be sieved before repeating the above steps with the identified powder.

[0034] Prior to validation, the composite powders may be mixed.

[0035] Supplying the metal powder from the powder container to the additive manufacturing system may include supplying the metal powder to a powder storage repository within the additive manufacturing system, wherein the amount of metal powder supplied is sufficient to form at least two layers of the metal powder.

[0036] Solidifying at least a portion of the metal powder layer may include bonding, sintering, and / or melting.

[0037] Ascertaining the quality of the composite powder may include (i) measuring and evaluating at least one powder material parameter of the composite powder, and / or (ii) examining physical movement data of the powder. The at least one powder material parameter of the composite powder may be stored in a data repository.

[0038] The powder physical movement data may include powder storage data, an identification of the additive manufacturing system, the number of times the powder has been delivered to the additive manufacturing system, and / or the number of times the powder has been mixed with a second powder.

[0039] Process data relating to at least one of the steps may be collected, and the collected process data may be stored in a data repository. The process data may include a laser power during the solidification step, a speed of the laser during the solidification step, or a thickness of the formed layer. Verifying the quality of the composite powder may include examining the collected process data.

[0040] The powder material parameters of the composite powder may be interstitial element chemistry, substitutional element chemistry, trace element analysis, apparent density, tapped density, particle size distribution, moisture, powder shape, powder morphology, Hall flow, Carney flow, sieve specification, trapped gas content, rheometric stability index, and / or angle of repose.

[0041] Measuring at least one powder material parameter of the composite powder may include capturing an optical image, capturing a scanning electron microscope image, capturing a cross-sectional image, performing a coulometric titration, and / or performing a pycnometry measurement.

[0042] The sealed powder container may comprise a shipping powder container, and the first metal powder may be shipped in the shipping powder container after its production, in which case the first metal powder may be virgin metal powder, and the first metal powder may be transferred from the shipping powder container to the sealed meal powder container prior to performing the steps outlined above.

[0043] In yet another aspect, various embodiments of the invention relate to a method for continuous closed loop metal powder management for additive manufacturing, the method comprising using an automated metal powder transfer system to transfer virgin metal powder suitable for additive manufacturing from a hopper, the hopper including at least one sensor, tracking device, or optical device, to a closed powder container, the powder container including at least one container sensor, container tracking device, or container optical device, the powder container being connected to an additive manufacturing system to perform the powder transfer in a closed loop.

[0044] The metal powder from the powder container is fed to an additive manufacturing system. The additive manufacturing system is operated to form at least one layer of the metal powder on a build plate of the additive manufacturing system. A portion of the at least one metal powder layer is solidified and an excess portion of the metal powder layer is left in powder form. These two steps are repeated at least once.

[0045] The excess metal powder is transferred from the additive manufacturing system to a powder container, a second container, or an internal powder container. A composite powder is formed by adding unused metal powder to the powder container, the second container, or the internal powder container, and the quality of the composite powder is verified. With the verified composite powder, the previous steps starting with connecting the metal powder to the additive manufacturing system are repeated at least once. Powder physical movement data associated with at least one of the above steps is collected and stored in a data repository. The sensor, tracking device, optical device, container sensor, container tracking device, and / or container optical device are electronically accessible during each of these steps. [Brief description of the drawings]

[0046] [Figure 1] FIG. 1 is a schematic diagram illustrating a closed loop metal powder management system for additive manufacturing, in accordance with an embodiment of the present invention.

[0047] [Diagram 2] FIG. 1 is a schematic diagram illustrating a closed-loop metal powder management system for additive manufacturing in large powder bed systems, in accordance with an embodiment of the present invention.

[0048] [Diagram 3] FIG. 1 is a schematic diagram illustrating a closed-loop metal powder management system for additive manufacturing in a compact powder bed system utilizing a reduced volume container in accordance with an embodiment of the present invention.

[0049] [Figure 4] 1 is an engineering sketch illustrating an example of an apparatus that may be used within a metal powder management system in accordance with an embodiment of the present invention.

[0050] [Diagram 5] FIG. 2 is a schematic diagram illustrating an exemplary embodiment of wireless data transfer, in accordance with an embodiment of the present invention.

[0051] [Figure 6a] FIG. 1 is a perspective view showing a base unit for receiving a powder hopper according to an embodiment of the present invention.

[0052] [Figure 6b] FIG. 2 is a front view showing an automatic decanting system according to an embodiment of the present invention.

[0053] [Figure 6c] FIG. 2 is a front view illustrating an automated docking station, according to an embodiment of the present invention.

[0054] [Figure 7] 1 is a photograph of a closed loop metal powder management system in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] [Detailed Description] Closed Loop Metal Powder Management Description and Benefits 1, a closed-loop metal powder management system 100 for additive manufacturing according to an embodiment of the present invention includes: (a) a raw material source (e.g., raw element or pre-alloyed master melt) used to produce metal powder; (b) a metal powder atomizer; (c) screening operations; (d) laboratory testing to authenticate the properties of the produced metal powder; (e) a metal powder container (e.g., hopper) loaded with the produced metal powder; (f) a digitally created additive manufacturing design (also called a "build file"); (g) an additive manufacturing machine; (h) recycling of the metal powder (which may include rescreening, filling or combining batches between different hoppers, and retesting powder properties); and (i) additively manufactured articles and specimens produced by solidifying the metal powder in the additive manufacturing machine. Data is collected from each of these operations and ingested, for example, into a cloud-based software system (j). The cloud-based software system (j) may be connected to the institute's ERP (enterprise resource planning) system or central IT system (k) for data aggregation and analysis.

[0056] Referring to FIG. 2 , a closed loop metal powder management system 200 for additive manufacturing in large powder bed systems according to an embodiment of the invention includes a production facility 210 from which metal powder is supplied, a container 220, e.g. a hopper, that is pre-filled with virgin, used (surplus) or mixed (hybrid) metal powder, an automated decanting system 230 that automatically docks with the container and loads the metal powder into an additive manufacturing machine 235, a powder addition station 240 that adds virgin metal powder to the (partially) depleted container in a controlled environment 240, a sieving station 250 that transfers the metal powder from one container to another and removes unwanted oversized particles and unwanted agglomerates, an extraction station 260 that extracts high value waste from the production stream for feedstock recycling 265, a mixing station 270 for mixing a combined batch of metal powders in a fully sealed container, and laboratory testing 280 of a retained sample of the combined / mixed powder to verify the quality of the material before putting the container back into the production cycle. The wifi icon at each station indicates wireless data transfer from smart devices in a closed loop system, which is captured in a data repository, such as a centralized software database.

[0057] The powder management system shown in Figure 2 is an example of a batch processing system. Batching refers to the sequential addition and / or removal of material from an additive manufacturing system in a controlled manner such that the bulk of the powder material can be clearly traced back to the original material lot. Batch processing involves feeding an externally blended or mixed lot to an additive manufacturing system, whereby the raw powder is removed from the system before refilling the system after a build cycle where it is replenished, sieved, and / or blended with powder from the same or a different batch external to the system.

[0058] Continuous processing refers to adding batches of material to an additive manufacturing system that includes an internal powder recirculation loop. In this method, powder from one or more externally held batches is added to the additive manufacturing system after each build cycle. However, after filling, the powder is typically not removed from the system but accumulates in an internal reservoir. After each build cycle, more powder feedstock is dispensed from the internal reservoir and a new build sequence begins. Thus, the circulating powder may contain a growing set of lots mixed in relatively different proportions. Thus, although the exact composition of the powder per sub-batch or lot at any one time is unknown, the original lot identifiers of all powders fed into the machine can be tracked as they are added.

[0059] The internal container is a hopper, bin, collection container, or other container plumbed to the additive manufacturing system as a fixed powder repository. The internal container is typically fabricated from stainless steel or similar material. Excess powder accumulated after a build is recirculated from the overflow bin, build chamber, and / or powder removal space of the additive manufacturing system to the internal container to await the next build preparation sequence. Typically, the powder is not removed from the system but is screened in-line to remove oversized particles before being returned to the internal container. In some embodiments, the internal container is housed in a separate device from the additive manufacturing chamber and the internal container is connected by a closed loop piping, so that powder does not need to be removed from the entire system. Such a multi-device closed loop system may be commercially referred to as, for example, an automatic powder recovery system, ICPM, ICM, etc.

[0060] Referring to FIG. 3 , a closed-loop metal powder management system 300 for additive manufacturing in miniature powder bed systems utilizing small volume containers according to an embodiment of the invention includes a production facility 210 from which metal powder is sourced, a container 320, e.g., a hopper, that is pre-filled with virgin, used, or mixed metal powder, an automated decanting system 330 for transferring ("topping off") metal powder from the larger hopper to the (somewhat) depleted, smaller volume second container 340, and a system for transferring ("topping off") metal powder from the larger hopper to the (somewhat) depleted, smaller volume second container 340. 0, a sieving station 350 that removes unwanted oversized particles and unwanted agglomerates, an extraction station 360 that extracts high value waste from the production stream for feedstock recycling 365, a multi-tiered bin 370 for filled bins ("WIP out" inventory), an AM machine 380 filled with powder bins of metal powder, a discharge stream 385 of used powder from the machine that has filled partially emptied bins, a bin 390 with used metal powder, and a multi-tiered bin 395 for used powder bins ("WIP in"). The wifi icons shown at each station indicate wireless data transfer from smart devices in a closed loop system that is captured in a data repository, such as a centralized software database.

[0061] For example, the closed-loop system shown in Figures 1-3 allows users to perform both batch and continuous AM operations while maintaining "behind the scenes" traceability, giving them peace of mind that the history of a metal powder can be audited and searched at any point in time. The system stores all user-captured data in one place and generates a digital "fingerprint" and taxonomy of the powder. Data may include statistical process control (SPC), key process variables (KPV), ambient / environmental information, real-time tracking information, physical and chemical properties of the powder, and any other user-defined relevant information specific to the manufacturing process or manufactured part.

[0062] With reference to Figures 1-3, the system described herein is a closed-loop, vertically integrated supply chain all the way from the metal powder factory to ensure a complete chain of custody and source of material.

[0063] Metal powders used in various embodiments of the present invention are elemental metals or alloys of two or more metals broken down into particles. The powders may contain single metal elements, mixed elemental particles, or pre-alloyed particles. Typical metal and alloy powders include those based on iron, nickel, cobalt, titanium, copper, aluminum, niobium, zirconium, and other primary elements. For example, a conventional alloy powder is titanium-6 aluminum-4 vanadium ("Ti6Al4V"). ​​The shape of the particles may be spherical, acicular, agglomerated, or amorphous. Typical sizes of the particles range from 1 μm to 250 μm. Metal powders may be produced using gas atomization, water atomization, plasma atomization, centrifugal processing, and other manufacturing methods.

[0064] The metal powder material is shipped in a pre-filled hopper-like container that serves as the essential "base unit" for powder transport throughout the entire additive manufacturing and recycling process. In this respect, the hopper acts similarly to an inkjet printer print cartridge, which can be filled with ink and plugged directly into the printer, and when empty, can be returned to the original manufacturer for environmentally friendly disposal, cleaning, or refilling with new ink.

[0065] In a closed loop, the controlled, i.e. inert, atmosphere is not compromised from the atomization to the printed part. The atmosphere can be monitored for any excursions or deviations from the desired conditions, allowing the user to make an informed decision on whether to continue the operation or not. For example, a container with metal powder can be filled with an inert gas such as argon or nitrogen up to a pressure of 0.2 bar, although this does not constitute a standard pressure vessel.

[0066] The metal powder is maintained in contact with an inert atmosphere from the time of loading at the manufacturing facility and throughout the process steps shown in Figures 1-3 to prevent or greatly reduce human exposure to the metal powder. The fine powders used in additive manufacturing can cause health hazards, including respiratory disorders, allergic reactions, carcinogenicity, or other adverse effects, if directly contacted by an operator. Currently available additive manufacturing systems require one or more steps of exposing the metal powder in an open container. A completely closed loop such as that shown in Figures 1-3 would eliminate all possible points of operator exposure.

[0067] 4, an engineering diagram includes a perspective view of various equipment that may be used in a closed loop metal powder management system. The equipment includes a container such as a hopper 400, a decanting system 410, an automated metal powder transfer system 420, an automated mixing system 430, an automated decanting system 430, and a software ecosystem 440.

[0068] Continuous closed-loop metal powder management method for additive manufacturing A closed loop metal powder management system, such as the system shown in Figures 1-3, may be used for additive manufacturing as follows.

[0069] In one embodiment, the metal powder from the sealed container can be used for additive manufacturing, the excess metal powder can be transferred back to the sealed container, and unused metal powder can be added to the excess metal powder to create a composite powder (also referred to herein as a mixed powder), which can then be used for additive manufacturing.

[0070] In particular, virgin metal powder suitable for additive manufacturing can be obtained disposed in a sealed powder container comprising a sensor, a tracking device, and / or an optical device. The sealed container can be a shipping container, and the virgin metal powder can be shipped in the shipping container after its production. Alternatively, the virgin metal powder from the shipping powder container can be transferred directly or indirectly to the sealed powder container, for example by using an automated metal powder transfer system, such as an automated docking system (see FIG. 6b and related description). In this embodiment, the shipping powder container comprises a sensor, a tracking device, and / or an optical device, and the sealed powder container comprises a container sensor, a container tracking device, and / or a container optical device.

[0071] To perform the metal powder transfer in a closed loop, the powder container is connected to the additive manufacturing system. In some embodiments, to perform the metal powder transfer in a closed loop, the powder container is connected to the additive manufacturing system with an automated metal powder transfer system. The automated metal powder transfer system is controllable by an electronic controller, such as a pneumatic controller and / or a programmable logic controller, and is adapted to control the supply of metered amounts of metal powder to the additive manufacturing system. Further details regarding the automated metal powder transfer system are provided below with respect to Figures 6a-6c.

[0072] The metal powder is delivered to the additive manufacturing system from a powder container. Delivering the metal powder may include delivering the powder to a powder storage repository within the additive manufacturing system, where the amount of metal powder delivered is sufficient to form at least two layers of the metal powder during a subsequent additive manufacturing step.

[0073] The additive manufacturing system is operated to form at least one layer of metal powder on a build plate of the additive manufacturing system. A portion of the at least one layer of metal powder is solidified and an excess portion of the metal powder layer is left in powder form. The bonding may include bonding, sintering, and / or melting.

[0074] After the steps of supplying and solidifying the metal powder have been repeated at least once, the excess metal powder from the additive manufacturing system is transferred to the powder container or a second powder container (for batch processing) or an internal powder container (for continuous processing). Unused metal powder is added to the excess metal powder in the powder container, the second powder container, or the internal powder container to form a composite powder. In some embodiments, the composite powder may be mixed.

[0075] The quality of the composite powder is confirmed. Confirmation of the composite powder may include measuring and evaluating at least one powder material parameter of the composite powder (e.g., interstitial element chemistry, substitutional element chemistry, trace element analysis, apparent density, tapped density, particle size distribution, moisture, powder shape, powder morphology, Hall flow, Carney flow, sieve specification, trapped gas content, rheometric stability index, and / or angle of repose). Measuring at least one powder material parameter of the composite powder may include capturing optical images, capturing scanning electron microscope images, capturing cross-sectional images, performing coulometric titration, and / or performing pycnometry measurements. The powder material parameters of the composite powder may be stored in a data repository. As used herein, a data repository is a digital store or archive of structured and / or unstructured information categorized and tagged with metadata (i.e., descriptors used to define the data). A data repository may be or include a single structured database, a set of databases, a data warehouse, a data lake, and other organizational tools for digital information.

[0076] In some embodiments, powder material parameters of the surplus powder may be measured. Additionally or alternatively, the quality of the blended powder may be confirmed by examining powder physical movement data, which may include powder storage data, an identification of the additive manufacturing system, the number of times the powder has been fed to the additive manufacturing system, and / or the number of times the powder has been blended with unused powder.

[0077] Process data may be collected and optionally stored in a data repository. The process data may include a laser power during the solidification step, a speed of the laser during the solidification step, or a thickness of a layer formed by the additive manufacturing system. Verifying the quality of the composite powder may also include examining the collected process data.

[0078] The above steps, starting with connecting the powder container to the additive manufacturing device, may be repeated at least once with the identified composite powder, which may be sieved prior to repeating these steps.

[0079] Powder physical movement data associated with at least one of the above steps is collected.

[0080] At least one powder material parameter of the composite powder and / or powder physical movement data is stored in a database.

[0081] In each of these steps, the sensor, tracking device, optical device, container sensor, container tracking device, and / or container optical device are electronically accessible.

[0082] In another embodiment, in an additive manufacturing system, a first metal powder is solidified. After the solidification step, the excess metal powder is transferred to an excess powder container and a second metal powder is added to form a composite powder. The first and second metal powders may have the same composition and may be from a single batch (i.e., from a single atomization heat or mix lot provided by a powder manufacturer). In other embodiments, the first and second metal powders may be from different batches (i.e., from different atomization heats or different mix lots). The first metal powder may be a virgin metal powder.

[0083] Laboratory Testing of Metal Powders Powders used in additive manufacturing as described herein include a plurality of particles of a metal, the particles having an average particle size selected from the range of 100 nanometers to 250 micrometers (e.g., 15 μm to 45 μm, or less than 22 μm).

[0084] Laboratory testing can be performed on samples obtained prior to the initial transfer of the metal powder to the AM machine (e.g., FIG. 1, step (d)) and / or at any stage within the AM cycle. Laboratory testing is performed by obtaining a retention sample of the metal powder. The sample amount can be, for example, 250 g of powder. Typically, users test powder after a recycling step, which may include mixing, sieving, or otherwise blending one powder batch with a virgin batch or another used (surplus) batch (i.e., recycled powder or a blended powder that includes virgin and recycled powder).

[0085] Users can define a sampling plan that specifies at which operational steps laboratory tests are performed and which set of tests are performed at each step. Test results are transcribed into the powder management software and tagged with sample identification details to ensure the powder's digital thread and digital fingerprint are maintained. Alternatively, test results may be transferred from laboratory instruments to the software data repository via an application programming interface (API).

[0086] Laboratory data collected on the powders may include any combination of chemical element measurements, particle size distribution (PSD) by sieve measurements or laser diffraction, Hall flow, Carney flow, angle of repose, apparent density, tapped density, pycnometry, cross-sectional images, digital camera images, particle color analysis, optical microscope images, confocal microscope images, scanning electron microscope images, moisture analysis by weight loss, coulometric titration, Karl Fischer titration, stability index, rheometry by basic flow index, morphology by circularity, elongation, convexity, or aspect ratio, and other measurements.

[0087] Powder measurements can help users determine if metal powders are degraded or out of specification - for example, excessively oxidized, contaminated, deformed or angular powders could pose a quality risk if recycled back into the additive manufacturing process.

[0088] The Metal Powder Management System software displays data for a batch of metal powder along with details of its entire lifecycle, such as the various bins and machines the powder may have passed through, highlighting and visualizing the importance of powder bin traceability and laboratory test results on the quality of the end-use printed part.

[0089] Filling an empty powder container In various embodiments of the invention, the powder container may be a hopper, container, bottle, or other receptacle. For example, the container may be a hopper made of stainless steel or a bottle made of plastic. The system is easier to manage using a large container as opposed to multiple small bottles. For example, a hopper with a capacity of 120-240 L is useful for various additive manufacturing operations. A sealed container reduces the risk of moisture ingress, which is detrimental to the flow of metal powder. A suitable hopper is, for example, the Carpenter Additive PowderTrace hopper available from Carpenter Additive, Inc., Philadelphia, Pennsylvania.

[0090] The powder container is filled with metal powder by manually or automatically transferring powder from another container. This operation may be performed under controlled conditions, such as an inert atmosphere. After the powder container is filled, it may be filled with an inert gas, such as argon, to prevent moisture and oxygen from coming into direct contact with the powder.

[0091] Monitoring environmental and ambient conditions for metal powders In various embodiments of the invention, the powder container (e.g., hopper) and other powder processing equipment (e.g., sieves, mixers, AM machine travel tracks, etc.) have electronic sensors for real-time and in-situ monitoring of ambient conditions or environmental conditions within the hopper. The sensors can measure any combination of oxygen, temperature, pressure, humidity, powder color in the visible light spectrum using a camera, color in the infrared spectrum, powder flowability, powder morphology, level of powder in the powder container, mass of powder in the powder container, powder contamination, and other properties. Contamination can be, for example, water / moisture, foreign objects, other powder alloys, etc.

[0092] Data from the sensors is transmitted wirelessly (e.g., via wifi or low-power radio signals) to an electronic receiving hub within the facility, which logs and stores the information along with batch and hopper identification information to ensure traceability.

[0093] With reference to FIG. 5, the wifi icon indicates wireless data transfer from smart devices in a closed loop system to a data repository such as a centralized software database. In this illustrated example, a container 220 (e.g., a hopper) containing metal powder is moved from a logistics area 500, which has a temperature of 8° C. and a humidity of 40%, to an AM production cell 510. In the AM production cell, the temperature of the hopper remains the same, but the humidity has dropped to 20%. However, the ambient temperature of the AM production cell 520 is higher, at 28° C. When an operator opens the hopper, this temperature difference can cause moisture to condense onto the metal powder, affecting the quality of the metal powder. A software-based metal powder management system 530 monitors all sensors from the logistics area 500 and the AM production cells 510, 520 and provides a signal to the user that it is "not safe to open" if the hopper is opened, as the dew point will be too high, and the user should wait X hours. Once the temperature reaches equilibrium 535 (e.g., after X hours (at 25° C. temperature and 20% humidity)), the software provides a signal 540 that the hopper is “safe to open” and metal powder can be loaded into the additive manufacturing machine 235.

[0094] In some embodiments, the sensor or device may have a visual "go / no go" signal, such as a colored light, that alerts the end user when the metal powder is safe to use or safe to transfer. For example, a "safe to use" condition is when the powder temperature is in equilibrium with the temperature of the surrounding AM facility after it has been transferred from another location. If the temperature difference is too great, moisture from the ambient air may condense on the powder below its dew point, causing a loss of powder quality or unwanted moisture ingress. This moisture may adversely affect the properties of the AM part through poor spreadability (powder "clumping"), hydrogen embrittlement, or other deleterious mechanisms. In other embodiments, the visual signal may alert the end user to a possible quality bias identified in laboratory or in-situ characterization data from a powder batch.

[0095] In other embodiments, the powder container (e.g., hopper) may also function as a geographic location tracker to maintain traceability of the physical location of the powder hopper at any point within the closed loop system and throughout the powder's lifecycle, for example using radio frequency identification (RFID) or global positioning system (GPS).

[0096] In some embodiments, the powder container may include an optical device, such as a digital camera, infrared camera, or other imaging device, to monitor the powder morphology and color in real time.

[0097] Loading Metal Powder into an Additive Manufacturing Machine Using an Automated Powder Transfer System 6a-6c, an automated metal powder transfer system for automated transfer of metal powder to an additive manufacturing machine (e.g., additive manufacturing machine 235) will now be described in more detail. In various embodiments of the invention, the metal powder can be loaded directly into a build chamber, a discharge, or a separate storage facility within the additive manufacturing machine. Transfer may occur from a stainless steel metal powder hopper using an automated metal powder transfer system designed to receive the metal powder hopper or other powder container.

[0098] The automatic metal powder transfer system is designed to be adaptable to several different additive manufacturing equipment using standard adapters. The layout and footprint of the automatic metal powder transfer system is designed to match the size of the hopper or other powder container, minimizing the utilization of floor space on the manufacturing floor. The automatic metal powder transfer system is designed to load the hopper or other powder container using a forklift with automatic guiding, which places the hopper accurately on the base. The automatic metal powder transfer system forms a sealed connection with the hopper. Through a programmable logic controller (PLC), the user can specify the amount of powder to be transferred to the additive manufacturing machine. The system can transfer a specified volume or mass of metal powder from the hopper to the additive manufacturing machine by vacuum conveying.

[0099] In particular, FIG. 6A is a perspective view showing a base unit 600 for receiving a powder container (e.g., a metal powder hopper), according to an embodiment of the present invention. The base unit includes two platform arms 610 configured to receive a powder hopper capable of accommodating, for example, 120-240 liters of metal powder. The platform arms may have vertical portions 620 (edges) on the sides and back to allow for automatic guiding of the incoming powder hopper. Each platform arm may have a length, for example, 1 m-2 m, a height, for example, 0.15 m, and a width, for example, 0.15 m, and may be made of a rigid material, such as stainless steel. The platform arms may be spaced far enough apart to allow placement of the bottom of the powder hopper between the vertical portions, for example, the distance between two opposing vertical edges along the two platform arms may be 0.5-1 m.

[0100] To ensure square placement of the hopper, the top surface of the platform arm may be provided with a conical guide 630 configured to mate with a corresponding opening in the bottom surface of the hopper. In the illustrated embodiment, four guides are shown, although it will be understood that more or fewer guides may be included.

[0101] An adapter flange fitting 640 is located in the center of the base unit assembly. The adapter flange is configured to mate with a corresponding fitting on the hopper side, and the two fittings can be manually or automatically connected to initiate powder transfer.

[0102] The base unit includes a base disposed below the platform arm. The base may include two base members 650 disposed below the platform arm. The distance of the two platform arms from the floor may be adjustable. The platform arm and the base member of the base unit may be separated from each other, and a strain gauge or scale may be placed between them for real-time weight measurement. An example of a suitable strain gauge or scale is the KFH series gauge manufactured by Omega Corporation.

[0103] Figure 6B is a front view showing an automated metal powder transfer system including an automated decant system 330, according to an embodiment of the present invention. The automated decant system 330 includes the base unit 600 of Figure 6a disposed on a frame 660 (e.g., a stainless steel frame having a tray 665 disposed at the bottom of the frame). Conventional plumbing 670 with pipes, valves, and fittings is disposed to connect to an adapter flange on the base unit, to which a powder container can be connected.

[0104] In use, the container 320 (e.g., hopper) is placed on the base unit on top of the frame, and the second powder container 340 is placed on a tray on the bottom of the frame. The hopper 320 and powder container 340 may be connected via an adapter flange on the base unit and piping. Metal powder can be moved, or "decanted," from the upper hopper 320 to the lower second container 340 using a manual valve, a programmable valve, or other feed control means.

[0105] This layout is useful for maintaining closed-loop metal powder control for additive manufacturing devices that use relatively small amounts of metal powder (e.g., less than 120 liters). For example, this automated metal powder transfer system may be used with the closed-loop metal powder management system for additive manufacturing of FIG.

[0106] Thus, in various embodiments of the invention, the automated decanting system 330 shown in FIG. 3 may be used to transfer metal powder from a larger hopper to a smaller container, or vice versa. This may be necessary when a particular additive manufacturing machine is designed to receive a particular type of container. Rather than transferring the metal powder directly from the original hopper to the additive manufacturing machine, the powder is transferred indirectly, first to a replacement container and then to a build chamber, a discharge, or a separate storage facility within the additive manufacturing machine. The transfer of metered amounts of metal powder from the hopper to the separate container may be controlled by a pneumatic controller, or an electronic controller, such as a programmable logic controller (PLC).

[0107] FIG. 6c is a front view of an automated metal powder transfer system including a docking system 680 according to another embodiment of the invention. In this docking system, the base unit 610 of FIG. 6a is placed on the floor. The powder container 220 (e.g., hopper) is placed on the base unit. A rigid or flexible pipe assembly 685 is attached to an adapter flange (e.g., KF flange adapter) on the base unit and connects the hopper to a metal powder vacuum unit 690 or pneumatic vacuum conveyor that can be placed on the additive manufacturing machine (not shown). A suitable metal powder vacuum unit is the MULTIJECTOR® series pneumatic vacuum conveyor manufactured by Volkmann GmbH. A second metal powder vacuum unit 690′ is placed above the hopper and receives return material, e.g., excess metal powder, via another set of connecting piping (not shown). This docking system maintains a completely closed loop between the powder container (e.g., hopper) and the additive manufacturing machine.

[0108] This layout is useful for maintaining closed-loop metal powder control for additive manufacturing machines that use relatively large amounts of metal powder (e.g., 120 liters or more). For example, this automated metal powder transfer system may be used with the closed-loop metal powder management system for additive manufacturing of FIG.

[0109] In use, the metal powder is transferred to the additive manufacturing machine by creating a vacuum with a vacuum unit on top of the machine. Excess metal powder can be transferred from the additive manufacturing machine to a container (e.g., a hopper) by a vacuum created by a second vacuum unit above the hopper.

[0110] There may be a pressure imbalance between the "pre-filled" hopper with argon back pressure and the additive manufacturing machine. A pilot line system can be added to the powder transfer mechanism to balance the pressure and avoid overpressure. A sealing butterfly valve can also be added between the automatic docking station and the additive manufacturing machine to interlock with the machine atmosphere and maintain pressure safety. This system is designed to vent static electricity to ground to avoid sparks during metal powder transfer. The automatic docking station has an additional safety system with self-checking and alarms that can alert the user to unwanted build-up of static electricity.

[0111] Referring also to FIG. 2, the automated powder metal transfer system allows containers containing unused or other used powder metals to be connected on-site to a “docking hopper” in a controlled environment 240 for refilling and topping up depleted powder.

[0112] Referring to Figure 7, a photograph shows a layout of an exemplary closed loop metal powder management system, according to an embodiment of the present invention. The metal powder hopper 220 is placed on an automated docking system 680 and connected to the additive manufacturing machine 235 via rigid stainless steel piping 685. The transfer of metal powder from the container (e.g., hopper) to the additive manufacturing machine and vice versa is accomplished using two metal powder vacuum units 690, 690'. The transfer of metered amounts of metal powder is controlled by an electronic controller 700, such as a programmable logic controller, or a pneumatic controller.

[0113] Rigid tubing between the automated docking station and the AM machine is used to minimize the travel distance and bend radius of the metal powder, avoiding blockages and therefore maximizing uptime. Magnetic clamps for the tubing allow the unit to be connected to the AM machine without complex assembly (e.g., screwing or bolting to the machine). The connecting tubing is designed not to interfere with the machine's access panels, and the connecting tubing not only minimizes the footprint, but also allows for bidirectional movement of the metal powder for loading and unloading operations.

[0114] Metal powders can temporarily become self-supporting, causing "bridges" that impede flow in the vessel. This is a risk in powder systems where the hopper outlet is not designed to be conical, so vessels are sometimes designed with a cone angle to avoid this situation. Powders can flow in "core" or "mass" flow regimes, i.e., through the middle of the vessel opening (core) or along the sides of the vessel (mass). Since mass flow is preferred for better control, hoppers should be designed to facilitate mass flow of a wide variety of powders. This is achieved by steepening the angle of the hopper base leading to the outlet opening. Adding virgin metal powder on top of a recycled batch of metal powder in the vessel results in a "LILO" (last in, last out) inventory condition in the mass flow case, whereas the core flow case results in a "LIFO" (last in, first out) inventory order.

[0115] Executing an Additive Manufacturing Build Cycle Suitable additive manufacturing methods may be any of the seven categories of additive manufacturing identified by ASTM (i.e., Binder Jetting (BJT), Directed Energy Deposition (DED), Mask Image Projection-Based Stereolithography (MIP-SL), Material Extrusion (MEX), Material Jetting (MJT), Powder Bed Fusion (PBF), and Sheet Lamination (SHL) as defined in STM F2792-12a issued by ASTM Task Force F42 on Additive Manufacturing Technology. Derivative methods and combinations may also be used. Examples of additive manufacturing systems suitable for use with embodiments of the present invention include, for example, GE Additive, RENISHAW®, SLM Solutions, Desktop Metal, and the like.

[0116] During the additive manufacturing process, the metal powder lifecycle management system software can be used to monitor, collect, store, compile, process, and analyze key process variables and other information. For example, the system can record any combination of log files read from the additive manufacturing machine, temperature, humidity, process parameters (including laser speed, hatch spacing, beam size, beam speed, laser power, and other statistics), machine tool toolpath, or total incident laser energy (defined as the amount of laser energy integrated over the total exposed volume in the LPBF manufacturing process).

[0117] In one embodiment, the system monitors and records the quality of the exhaust gas stream from the additive manufacturing machine. For example, a smoke detection sensor can be used to record the quality of the exhaust gas in terms of "soot" or charred particles emanating from the additive manufacturing process.

[0118] Recycling, replenishing and retesting used metal powders A fundamental challenge for additive manufacturing users is the repeatability and reproducibility of parts throughout the metal powder lifecycle management, especially when the metal powder is used multiple times. Metal powders degrade when reused, which can affect the quality of additively manufactured parts. For each raw material and application, users need to develop a unique set of key process variables (KPVs) that can be used to determine the appropriate metal powder recycling amount. The metal powder management system disclosed herein allows users to monitor a wide range of statistics and conditions, and then use "big data" analytical tools to identify the fundamental KPVs when the operation moves to continuous production.

[0119] Referring to the powder recycling (h) and sieving stations 250, 350 in FIG. 1, blending or sieving of the metal powders can be performed as a separate step in situ within or between hoppers in a closed loop to produce a homogenous batch. In one example, the spent powder is sieved at an extraction station 260, 360, and the sieved oversized particles are placed in a separate hopper and sent back to the production facility or scrap yard as high value waste. After blending or sieving, a retained metal powder sample can be taken to repeat the powder laboratory testing, the results of which are loaded into the data collection software along with the traceability information for that batch.

[0120] In one embodiment, the hopper containing the used metal powder is heated using an electric heating jacket, an oil jacket, or placed in a heated oven while the hopper is evacuated by dynamic vacuum to reduce the moisture content of the powder before the hopper is reused.

[0121] Directing powder into container or surplus powder container After the AM step is complete, a decision must be made whether the excess powder metal should be returned to the hopper or to the excess powder metal hopper. The fate of the excess powder metal can be determined by statistical process control, KPV, or continuous monitoring of various properties of the powder, including flowability, rheology, chemistry, morphology, porosity, contamination, moisture content, recycling / transfer history, process data from the AM process, material property data from the finished part, etc. If any of these resulting measurements are out of specification at any point within the recycling strategy, the powder metal may be directed to a excess powder metal container (e.g., a hopper) for segregation and / or disposal into the waste stream.

[0122] A user may have multiple reuse strategies depending on the specific application and raw materials. In one embodiment, as the mass of metal powder is depleted during production, additional virgin metal powder is added and selectively blended by mixing and / or sieving (this is referred to as a "virgin add" top-off strategy). In another embodiment, multiple batches of recycled metal powder can be blended by mixing and / or sieving if the resulting metal powder meets the specification conditions determined by the user.

[0123] Testing of Additively Manufactured Articles and Specimens 1, the metal powder management system may also collect and store information gathered from laboratory testing regarding the properties of the additively manufactured samples. For example, tensile mechanical properties, fatigue properties, stress rupture, thermal conductivity, coefficient of expansion, microstructure, chemical properties, corrosion properties, magnetic properties, or any other material data may be collected from the additively manufactured and post-processed samples.

[0124] In one embodiment, the metal powder management system collects a wide range of materials data, recycling data, additive manufacturing process, and post-processing (e.g., heat treatment, chemical processing, hot isostatic pressing, etc.) data. The system enables users to collect statistically significant amounts of data, or "big data," across many process cycles and perform analytics, including machine learning, reinforcement learning, and other artificial intelligence techniques, to gain insights and optimize end-to-end processes to deliver high performance results.

[0125] Although the invention has been described in detail herein in connection with one or more preferred embodiments, it should be understood that the disclosure is merely exemplary and illustrative of the invention and is made solely for the purpose of providing a complete and enabling disclosure of the invention. The foregoing disclosure is not intended to be construed as limiting the invention or excluding other such embodiments, adaptations, variations, modifications, or equivalent arrangements, and the invention is limited only by the claims appended hereto and their equivalents.

Claims

1. 1. A closed loop metal powder management method for additive manufacturing, comprising: a) obtaining virgin metal powder suitable for additive manufacturing, the metal powder being disposed in a sealed powder container comprising at least one electronically accessible sensor, tracking device, or optical device, the sealed powder container being either (i) a shipping powder container in which the virgin metal powder is shipped following its production, or (ii) a powder container into which the virgin metal powder is transferred from the shipping container in a closed-loop controlled atmosphere; b) thereafter, placing the closed powder container in an automated metal powder transfer system to form a sealed connection therebetween, and connecting the powder container via a pipe assembly to an additive manufacturing system comprising the automated metal powder transfer system to perform powder transfer in a closed loop; (i) the automated metal powder transfer system is controllable by at least one of a pneumatic controller or an electronic controller and adapted to control the supply of metered amounts of metal powder to the additive manufacturing system; (ii) the automated metal powder transfer system comprises at least one platform arm configured to receive the closed powder container; and (iii) during powder transfer, the closed powder container is outside the additive manufacturing system; c) delivering the metered amount of metal powder from the powder container through the pipe assembly to the additive manufacturing system; d) operating the additive manufacturing system to form at least one layer of the metal powder on a build plate of the additive manufacturing system; e) solidifying a portion of the at least one layer of metal powder, with an excess portion of the layer of metal powder remaining in powder form; f) repeating steps d) and e) at least once; and g) transferring excess metal powder from the additive manufacturing system to the powder container, a second powder container, or an internal powder container; h) adding virgin metal powder to the excess metal powder in the powder container, second powder container, or inner powder container to form a composite powder; i) checking the quality of the composite powder; j) repeating steps b) to i) at least once with the confirmed hybrid powder; k) collecting powder physical movement data associated with at least one of steps a)-j); and l) storing said powder physical movement data in a data repository; Including, During each of steps a) through l), the at least one sensor, tracking device, or optical device is electronically accessible, and during steps a) through l), the virgin metal powder, surplus metal powder, and hybrid powder are maintained in a closed loop controlled atmosphere.

2. The closed loop metal powder management method of claim 1, wherein the sealed powder container includes at least one sensor adapted to measure at least one of oxygen in the powder container, temperature in the powder container, humidity in the powder container, pressure in the powder container, color of the powder in the powder container, morphology of the powder in the powder container, level of powder disposed in the powder container, mass of the powder disposed in the powder container, or contamination of the powder disposed in the powder container.

3. 10. The closed loop metal powder management method of claim 1, further comprising maintaining the powder and excess powder under an inert atmosphere during steps a)-l).

4. The method of claim 1 , further comprising measuring at least one powder material parameter of the surplus powder.

5. 2. The closed loop metal powder management method of claim 1, further comprising sieving the composite powder prior to step j) of repeating steps b) through i).

6. The method of claim 1 further comprising blending the composite powder prior to verification.

7. 2. The closed loop metal powder management method of claim 1, wherein step c) of supplying metal powder from the powder container to the additive manufacturing system comprises supplying the metal powder to a powder storage hangar within the additive manufacturing system, the amount of metal powder supplied being sufficient to form at least two layers of metal powder in step d).

8. The closed loop metal powder management method of claim 1 , wherein the solidifying step d) comprises at least one of bonding, sintering, or melting.

9. 2. The closed loop metal powder management method of claim 1, wherein verifying the quality of the composite powder comprises at least one of: (i) measuring and evaluating at least one powder material parameter of the composite powder; or (ii) examining powder physical movement data.

10. 2. The method of claim 1, wherein the powder physical movement data includes at least one of powder storage data, an identification of an additive manufacturing system, a number of times the powder has been fed to the additive manufacturing system, and a number of times the powder has been mixed with virgin metal powder.

11. The method of closed loop metal powder management of claim 1 , further comprising collecting process data relating to at least one of steps a) through j).

12. 1. A closed loop metal powder management method for additive manufacturing, comprising: a) obtaining a first metal powder suitable for additive manufacturing, the first metal powder being disposed in a sealed powder container comprising at least one electronically accessible sensor, tracking device, or optical device, the sealed powder container being either (i) a shipping powder container in which the first metal powder is shipped following its production, or (ii) a powder container into which the first metal powder is transferred from the shipping powder container in a closed-loop controlled atmosphere; b) thereafter, placing the closed powder container in an automated metal powder transfer system to form a sealed connection therebetween, and connecting the powder container via a pipe assembly to an additive manufacturing system comprising the automated metal powder transfer system to perform powder transfer in a closed loop; (i) the automated metal powder transfer system is controllable by at least one of a pneumatic controller or an electronic controller and adapted to control the supply of metered amounts of metal powder to the additive manufacturing system; (ii) the automated metal powder transfer system comprises at least one platform arm configured to receive the closed powder container; and (iii) during powder transfer, the closed powder container is outside the additive manufacturing system; c) delivering the metered amount of metal powder from the powder container through the pipe assembly to the additive manufacturing system; d) operating the additive manufacturing system to form at least one layer of the metal powder on a build plate of the additive manufacturing system; e) solidifying a portion of the at least one layer of metal powder, with an excess portion of the layer of metal powder remaining in powder form; f) repeating steps d) and e) at least once; and g) transferring excess metal powder from said additive manufacturing system to an excess powder container comprising at least one excess powder container sensor, excess powder container tracking device, or excess powder container optical device; h) adding a second metal powder to the excess powder container to form a composite powder; i) checking the quality of the composite powder in the surplus powder container; j) repeating steps b) through i) at least once with the verified composite powder disposed in the excess powder container; k) collecting powder physical movement data associated with at least one of steps a)-j); and l) storing said powder physical movement data in a data repository; Including, a) a controlled atmosphere of the first metal powder, the second metal powder, the excess metal powder, and the composite powder; and a controlled atmosphere of the first metal powder, the second metal powder, the excess metal powder, and the composite powder.

13. 13. The closed loop metal powder management method of claim 12, wherein the first metal powder and the second metal powder have the same composition.

14. 13. The closed loop metal powder management method of claim 12, wherein the first metal powder and the second metal powder are from different batches.

15. 13. The method of claim 12, wherein the first powdered metal is virgin powdered metal.

16. The closed loop metal powder management method of claim 12, wherein the sealed powder container includes the at least one sensor adapted to measure at least one of oxygen in the powder container, temperature in the powder container, humidity in the powder container, pressure in the powder container, color of the powder in the powder container, morphology of the powder in the powder container, level of the powder disposed in the powder container, mass of the powder disposed in the powder container, or contamination of the powder disposed in the powder container.

17. 13. The method of closed loop metal powder management of claim 12, wherein the excess powder container comprises an internal powder container or an external powder container.

18. 13. The closed loop metal powder management method of claim 12, further comprising maintaining the first metal powder, the second metal powder, the excess metal powder and the hybrid powder under an inert atmosphere during steps a)-l).

19. The method of claim 12 further comprising measuring at least one powder material parameter of the surplus powder metal.

20. 13. The closed loop metal powder management method of claim 12, further comprising sieving the composite powder prior to step j) of repeating steps b) through i).

21. The closed loop metal powder management method of claim 12 further comprising blending the composite powder prior to verification.

22. 13. The closed loop metal powder management method of claim 12, wherein step c) of supplying metal powder from the powder container to the additive manufacturing system comprises supplying the metal powder to a powder storage hangar within the additive manufacturing system, the amount of metal powder supplied being sufficient to form at least two layers of metal powder in step d).

23. The closed loop metal powder management method of claim 12 , wherein the solidifying step d) comprises at least one of bonding, sintering, or melting.

24. 13. The closed loop metal powder management method of claim 12, wherein verifying the quality of the composite powder comprises at least one of: (i) measuring and evaluating at least one powder material parameter of the composite powder; or (ii) examining physical movement data of the powder.

25. 13. The method of claim 12, wherein the powder physical movement data comprises at least one of powder storage data, an identification of the additive manufacturing system, a number of times the powder has been fed to the additive manufacturing system, and a number of times the powder has been mixed with the second powder.

26. The closed loop metal powder management method of claim 12, further comprising collecting process data relating to at least one of steps a)-j).

27. 1. A closed loop metal powder management method for additive manufacturing, comprising: a) using an automated powder metal transfer system to transfer a measured amount of virgin powder metal suitable for additive manufacturing in a closed loop from a shipping container including at least one electronically accessible sensor, tracking device, or optical device to a sealed powder container including at least one electronically accessible container sensor, container tracking device, or container optical device, wherein during the transfer, the shipping container is located at an upper portion of the automated powder metal transfer system and the sealed powder container is located at a bottom portion of the automated powder metal transfer system below the shipping container; b) thereafter connecting said closed powder container to an additive manufacturing system to perform powder transfer in a closed loop; c) supplying metal powder from the powder container to the additive manufacturing system; d) operating the additive manufacturing system to form at least one layer of the metal powder on a build plate of the additive manufacturing system; e) solidifying a portion of the at least one layer of metal powder, with an excess portion of the layer of metal powder remaining in powder form; f) repeating steps d) and e) at least once; and g) transferring excess metal powder from the additive manufacturing system to the powder container, a second powder container, or an internal powder container; h) adding virgin metal powder to the excess metal powder in the powder container, the second powder container, or the inner powder container to form a composite powder; i) checking the quality of the composite powder; j) repeating steps b) to i) at least once with the confirmed hybrid powder; k) collecting powder physical movement data associated with at least one of steps a)-j); and l) storing said powder physical movement data in a data repository; Including, During each of steps a) through l), the at least one sensor, tracking device, optical device, container sensor, container tracking device, or container optical device is electronically accessible, and during steps a) through l), the virgin metal powder, surplus metal powder, and hybrid powder are maintained in a closed loop controlled atmosphere.

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