Additive manufacturing (AM) of metallic parts provides engineers with unprecedented design freedom. This enables designers to consolidate assemblies, lightweight designs, create intricate internal geometries for enhanced fluid flow or heat transfer performance, and fabricate complex components that previously could not be manufactured. While these design benefits may come “free” in many cases, it necessitates an understanding of the limitations and capabilities of the specific AM process used for production, the system-level design intent, and the postprocessing and inspection/qualification implications. Unfortunately, design for additive manufacturing (DfAM) guidelines for metal AM processes are nascent given the rapid advancements in metal AM technology recently. In this paper, we present a case study to provide insight into the challenges that engineers face when redesigning a multicomponent assembly into a single component fabricated using laser-based powder bed fusion for metal AM. In this case, part consolidation is used to reduce the weight by 60% and height by 53% of a multipart assembly while improving performance and minimizing leak points. Fabrication, postprocessing, and inspection issues are also discussed along with the implications on design. A generalized design approach for consolidating parts is presented to help designers realize the freedoms that metal AM provides, and numerous areas for investigation to improve DfAM are also highlighted and illustrated throughout the case study.

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Purpose The continued improvement of additive manufacturing (AM) processing has led to increased part complexity and scale. Processes such as electron beam directed energy deposition (DED) are able to produce metal AM parts several meters in scale. These structures pose a challenge for current inspection techniques because of their large size and thickness. Typically, X-ray computed tomography is used to inspect AM components, but low source energies and small inspection volumes restrict the size of components that can be inspected. This paper aims to develop digital radiography (DR) as a method for inspecting multi-meter-sized AM components and a tool that optimizes the DR inspection process. Design/methodology/approach This tool, SMART DR, provides optimal orientations and the probability of detection for flaw sizes of interest. This information enables design changes to be made prior to manufacturing that improve the inspectabitity of the component and areas of interest. Findings Validation of SMART DR was performed using a 40-mm-thick stainless-steel blade produced by laser-based DED. An optimal orientation was automatically determined to allow radiographic inspection of a thickness of 40 mm with a 70% probability of detecting 0.5 mm diameter flaws. Radiography of the blade using the optimal orientation defined by SMART DR resulted in 0.5-mm diameter pores being detected and indicated good agreement between SMART DR’s predictions and the physical results. Originality/value This paper addresses the need for non-destructive inspection techniques specifically developed for AM components.

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