Robust Metal Additive Manufacturing Process Selection and Development for Aerospace Components

Paul Gradl; Omar Mireles; Darren Tinker; Will Tilson; Colton Katsarelis; Alison Park; Brian West

NASA NTRS · 20210022812

Robust Metal Additive Manufacturing Process Selection and Development for Aerospace Components

Paul Gradl·Omar Mireles·Darren Tinker·Will Tilson·Colton Katsarelis·Alison Park·Brian West

Abstract

Metal additive manufacturing (AM) is a generic term that captures a variety of fabrication techniques. Each of these manufacturing process has unique advantages, applications for use, and challenges. The most common AM processes in use include Powder Bed Fusion (PBF) and Directed Energy Deposition (DED) as well as many solid state processes. While detailed research has been conducted among many of the processes including parameters and material properties, navigating which processes are best to select is difficult as it is based on component requirements. The focus of this presentation is to provide an overview of considerations for each of metal AM process selection for aerospace components based on various attributes. These attributes include geometric considerations, metallurgical characteristics, cost basis, post-processing and maturity of the processes. The data for these trade selections are based on studies that NASA as performed internally and with academic and industry partners. These studies include multiple AM build experiments to evaluate (1) geometric variations and constraints within the processes, (2) alloy characterization and mechanical testing, (3) pathfinder component development and hotfire evaluations, and (4) certification approaches. This presentation summarizes these results and meant to introduce various considerations when designing a metal AM component.

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Additive Manufacturing AM Process Selection Aerospace Liquid Rocket Engines Laser Powder Bed Fusion L-PBF Directed Energy Deposition DED Cold spray Microstructure TRL

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Paul Gradl, Omar Mireles, Darren Tinker, Will Tilson, Colton Katsarelis, Alison Park, Brian West. Robust Metal Additive Manufacturing Process Selection and Development for Aerospace Components. https://ntrs.nasa.gov/citations/20210022812

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