Summary: Additive manufacturing (AM) proposes a novel paradigm for engineering design and manufacturing, which has profound economic, environmental, and security implications. The design freedom offered by this category of manufacturing processes and its ability to locally print almost each designable object will have important repercussions across society. While AM applications are progressing from rapid prototyping to the production of end‐use products, the environmental dimensions and related impacts of these evolving manufacturing processes have yet to be extensively examined. Only limited quantitative data are available on how AM manufactured products compare to conventionally manufactured ones in terms of energy and material consumption, transportation costs, pollution and waste, health and safety issues, as well as other environmental impacts over their full lifetime. Reported research indicates that the specific energy of current AM systems is 1 to 2 orders of magnitude higher compared to that of conventional manufacturing processes. However, only part of the AM process taxonomy is yet documented in terms of its environmental performance, and most life cycle inventory (LCI) efforts mainly focus on energy consumption. From an environmental perspective, AM manufactured parts can be beneficial for very small batches, or in cases where AM‐based redesigns offer substantial functional advantages during the product use phase (e.g., lightweight part designs and part remanufacturing). Important pending research questions include the LCI of AM feedstock production, supply‐chain consequences, and health and safety issues relating to AM.

Awarded with the CIRP LCE2017 Best Paper "LEO" award.While additive manufacturing applications are progressing from rapid prototyping to the production of end-use products, the environmental impacts caused by these manufacturing processes and related material flows are still a rather open question. Therefore, this paper will provide an overview of available life cycle inventory data and compare the environmental impact caused by a series of additive manufacturing processes: selective laser melting, selective laser sintering, electron beam melting, fused deposition modelling and stereolithography. Next to the energy and resource consumption of the AM unit processes itself also the impact caused during the (powder) material production and part post treatment are addressed. From environmental perspective it’s clear that the additional generated impacts during manufacturing should be compensated by functional improvements during the use phase of the AM manufactured part. As example, the case of lightweight components is discussed.status: publishe