RT&L FOCUS AREA(S): General Warfighting Requirements (GWR) TECHNOLOGY AREA(S): Air Platforms;Materials / Processes;Weapons OBJECTIVE: Develop a novel low-cost, high-yield metallic-powder production system capable of rapidly producing small batches (i.e., tens of grams to hundreds of kilograms) of feedstock for Additive Manufactured (AM) structural parts and repairs. DESCRIPTION: Current production systems are capital and labor intensive, making the powders inordinately expensive, especially for small batches. The AM powders are also very costly with limited availability due to low yield and the needs for specific, high-quality, narrow particle size distributions (PSD) that are optimal for each AM process. For instance, the powder particles are usually specified with a size range of 15-45 m diameter (dia.) for Laser Beam Melted (LBM)/Powder Bed Fusion (PBF) process, 45-106 m dia. for Electron Beaming Melting (EBM)/PBF, and 45-75 m dia. for Directed Energy Deposition (DED)/Laser Engineered Net Shaping (LENS). In the academic and research arena, the lack of willing powder producers, long lead time, and high cost for low-quantity orders severely hinder the ability to rapidly validate and optimize the chemical compositions, microstructures, and mechanical performance for various material designs. To accelerate the performance optimization and verification of new alloy designs, high-quality feedstock in affordable small batches needs to be readily obtained for build trials. As AM is adopted by more and more manufacturers, part designs will become more diversified and customized. There will be lower manufacturing volume of custom designed parts and assemblies as compared to the traditional mass production. A similar trend will also develop for new alloys used for different future applications. There will be more demand for alloys that are specifically designed for specific applications and less for standard alloys. This will drive the production of feedstock toward smaller scales and perhaps distributed where it is needed. In the Maintenance, Repair and Overhaul (MRO), and fleet sustainment communities, the availability of small quantity supply with short-turnaround time without the needs for provisioning and storage is essential for timely part replacement and repairs. A low-cost, small-batch, high-yield feedstock production system for AM processing is required. The targeted cost for a production unit should be in the range of $10K's to low $100K's. The system must be user-friendly, and provide sufficient adjustable controls, coupled with integrated internal monitoring sensors, to assure consistent and uniform high-quality powders (Refs. 10-13) (e.g., particle size distribution, sphericity, internal porosity, surface roughness, oxygen level, amount of satellite particles that adhere to spherical powders, flowability). It must also be capable of making high-yield (50% or greater), small batches (tens of grams to hundreds of kilograms) of traditional metallic powders (e.g., Ti64, 17-4PH SS, IN718, AlSi10Mg), as well as specialty designed alloys. Integrated Computational Material Engineering (ICME)-based modeling & simulation (M & S) of the powder fabrication process should be utilized to support the system design and development. PHASE I: Develop and design a low-cost, small-batch, high-yield powder production system for metal AM applications. Perform system design, M & S, and associated experimental testing to validate the concept (Refs. 14 & 15). Generate preliminary performance and system specifications for the proposed design including powder handling, storage, and disposal procedures. The Phase I effort will include prototype plans to be developed under Phase II. PHASE II: Develop, design and prototype a complete powder production system for AM applications. Demonstrate that the metallic powders can be successfully used for AM of aircraft components. Update performance and system specifications and special handling procedures including powder handling, storage, and disposal procedures. PHASE III DUAL USE APPLICATIONS: Conduct final system checkout and acceptance testing. Perform production demonstration for multiple types of materials and alloys. Finalize performance and system specifications and special handling procedures. This topic has a great and widespread potential benefit to commercial sectors ranging from academic research arena to the automobile industry. REFERENCES: 1. Dietrich, S., Wunderer, M., Huissel, A. and Zaeh, M. F. A new approach for a flexible powder production for additive manufacturing. Procedia Manufacturing, Vol. 6, 2016, pp. 88-95. https://doi.org/10.1016/j.promfg.2016.11.012. 2. Anderson, I. E., White, E. M. H. and Dehoff, R. Feedstock powder processing research needs for additive manufacturing development. Current Opinion in Solid State and Materials Science, 22(1), February 2018, pp. 8-15. https://doi.org/10.1016/j.cossms.2018.01.002. 3. Kotlyarov, V. I., Beshkarev, V. T., Kartsev, V. E., Ivanov, V. V., Gasanov, A. A., Yuzhakova, E. A., Samokhin, A. V., Fadeev, A. A., Alekseev, N. V., Sinayskiy, M. A. and Tretyakov, E. V. Production of spherical powders on the basis of group IV metals for additive manufacturing. 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