Laser powder bed fusion (L-PBF) additive manufacturing: On the correlation between design choices and process sustainability

The specific energy consumption of Additive Manufacturing (AM) unit processes for the production of metal parts could be much higher than that of more traditional manufacturing routes, such as machining. However, AM, due to its intrinsic process peculiarities, including the flexible realization of (almost) any kind of complex shape, has a great potential for improving the material use efficiency, with positive environmental impact benefits from the material production to the product use and disposal at the end of first life. Aim of this paper is to assess the role of the design choices on the environmental AM process sustainability. An integrated design methodology (accounting for the product re-design via topological optimization, the design of support structures, and the design of allowances and features for post-AM finishing operations) for components produced by means of laser powder bed fusion processes is considered. One resource (the cumulated energy demand) and one emission (carbon dioxide) are assumed as metrics for the impact assessment across the product life cycle. The results demonstrate the importance of a proper design for AM to improve the overall energy and emission saving potential.