Metal Additive Manufacturing of Refractory Metal Nuclear Reactor Components

In this 6-month Small Business Innovation Research (SBIR) program, Amaero Advanced Materials & Manufacturing, Inc. (AAMM), a Delaware corporation with production facilities located in McDonald, TN, will develop and demonstrate a novel method for the domestic (US) fabrication of non-fissile nuclear reactor core components from Zircaloy-4 (Zr-4). Spherical Zr-4 powder will be produced by the process of Electrode Inert Gas Atomization (EIGA). Material to be atomized is delivered to the EIGA in the form of an electrode (solid round bar). Electrodes are typically produced by rolling, forging, extrusion, or casting. Continuously increasing demands for Zr-4 alloy for reactor core fabrication greatly strain US mill capacity and forces reliance on imported materials from Europe and China. In this research effort, electrodes will be domestically (US) produced from Zr-4 waste products, consolidated into solid bar by AAMMĺs IPP process. Atomization will be performed in AAMMĺs EIGA Premium system, located in McDonald, TN. The EIGA atomization process is a contact free method for producing high quality, contaminant free, spherical metal powders, of the type and quality necessary for fission reactor core fabrication. Metal additive manufacturing (AM), also known as 3D printing, will be employed to fabricate artifacts that demonstrate the feasibility of printing structural reactor core components. The printing portion of this research effort will begin with a robust design of experiments (DOE) that will develop high density printing parameters for the successful deposition of Zr-4. Using those parameters, artifacts will be printed that demonstrate the capability of Laser Powder Bed Fusion (LPBF) to print Zr-4 in shapes, wall thicknesses and surface finishes appropriate for reactor core fuel assemblies. Finally, a techno-economic study will be conducted and reported on the full-scale feasibility for the IPP process to domestically (US) recycle Zr-4 chips and other Zr-4 remnants from manufacturing waste streams into EIGA electrodes, with a lower cost of production than tradition mill products, and with lower energy consumption and lower CO2 emissions. The report will address the applicability of LPBF, and possibly other modalities of additive manufacturing, to improve supply chain flexibility and agility for producing SMR and MMR reactor core components.