CAREER: Bridging Research & Education in Delineating Fatigue Performance & Damage Mechanisms in Metal Fused Filament Fabricated Inconel 718

Florida Polytechnic University, Lakeland FL

Investigators

Abstract

Current metal additive manufacturing/3D printing technologies (i.e., laser powder bed fusion, binder jetting, and direct energy deposition) for rapid manufacturing of structural components are extremely expensive, limiting their use on a broader scale. Alternatively, metal fused filament fabrication additive manufacturing technology, which melts and extrudes metal powder bound in a plastic filament, provides a low-cost approach for rapid part production, with the added benefits of safety and ease of operation. This Faculty Early Career Development (CAREER) award will support research that advances the field of mechanics by delineating the overall fatigue performance and governing failure mechanisms exhibited by metal fused filament fabricated nickel-based superalloy, used in structural components within the aviation, space, energy, propulsion, and automotive industries. Mitigation of limitations (i.e., shrinkage, porosity, microstructural defects etc.) associated with this technology will be assessed through post-processing techniques, including their role on impacting fatigue performance. Integration of research findings with educational enhancement will be used to develop educational outreach activities for middle and high school students on metal fused filament fabrication additive manufacturing technology, along with incorporation of project-based learning activities within the academic curriculum. Research opportunities and professional training of under-represented minorities will be part of the study, including propelling undergraduate to graduate educational transition through an Accelerated B.S. to M.S. (4+1) program along with establishment of a research symposium to enhance public scientific literacy. This CAREER award supports fundamental research to enhance understanding of the mechanics exhibited by low-cost metal fused filament fabricated Inconel 718, subject to a variety of fatigue tests (i.e., axial, rotating beam, and torsional fatigue), reflective of the realistic mechanical loading environments experienced by structural components. The study intends to investigate the interaction of fatigue loading condition and microstructural defect distribution on fatigue failure. The role of build orientation and post-processing techniques on mitigation of these defects for enhanced fatigue performance will be explored. Fatigue fracture surface analysis, microstructural evolution, and assessment of microstructural defects introduced through this technology will be performed using a combination of material characterization techniques/microscopy. It is anticipated that this study could pave the next frontier in low-cost additive manufacturing to design structural components with the potential to meet basic mechanical performance functional requirements. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.