Sustainability: 3D printing

13.02.2024

Many companies need to make their processes more environmentally friendly and sustainable in order to achieve climate-neutral production. Financial pressure is also ensuring that the topic of energy and resource efficiency is becoming more of a focus. Energy saving, reducing CO ₂ emissions and saving resources are relevant goals in the context of environmental sustainability. Can new additive manufacturing (AM) technologies help to achieve the desired sustainability goals?

With the help of a life cycle analysis, the potential environmental impact and energy balance of a product can be systematically analyzed. The environmental impacts that arise during the production, use and disposal of the product are considered. Based on the results of the life cycle analysis, different manufacturing processes can be compared with each other in terms of their proportionate energy requirements and proportionate CO ₂ emissions over the entire life cycle.

Sustainability: traditional processes vs. 3D printing

In various studies, the environmental impact of established production technologies such as casting processes or machining were compared with additive manufacturing technologies on the basis of a life cycle analysis. Among other things, additive manufacturing processes such as electron beam melting, wire arc additive manufacturing and binder jetting with metallic materials were analyzed [1,2]. The additively manufactured components were previously topologically optimized and the starting material was replaced by an AM material. Depending on the component, this led to material savings of 15.5% and 69% for binder jetting and selective laser melting respectively. As a result of these studies, it was determined that the casting processes have a lower energy requirement than the additive processes. This can mainly be attributed to the reduced energy requirement during raw material production. In comparison, the binder jetting process has the highest CO ₂ emissions, which can be explained by the removal of the binder during the process. It was also found that selective laser melting emits less CO ₂ emissions than the casting process when using renewable energy sources.

In another study, Direct Energy Deposition (DED) was chosen as the additive process [3]. The component produced was not topologically optimized for the AM process and only the production phase was considered as part of the life cycle analysis. As a result of the study, the DED process performed worse than the traditional process in terms of its environmental impact. This was attributed to the low powder efficiency and the higher energy requirements of the AM process. According to the current state of the art, casting processes are the more environmentally friendly processes, especially for production series with large quantities and comparatively simple component geometries. With increasing demands on the complexity of the components, casting processes reach their limits, making machining necessary. In machining processes, the component is obtained from a raw part by removing material. At the end of the process, a large proportion of the starting material is usually produced as material waste. By replacing machining processes with additive manufacturing technologies, this proportion of raw material can be reduced, which leads to savings in energy and CO ₂ emissions, particularly in the area of raw material production.

Less material usage, more design freedom

A key advantage of additive manufacturing processes is the freedom of design and therefore the ability to realize very complex component geometries in the process. The result is considerable material savings compared to machining processes. By optimizing the topology of the components (optimized shape taking into account the mechanical load of the component), the amount of material required can be further minimized and resources saved. It is important to note that the proportion of material saved always depends on the component geometry itself

Potential of additive manufacturing for more sustainable production

In principle, additive manufacturing processes can contribute to achieving ecological sustainability goals. Particularly in the area of complex component geometries, the use of additive manufacturing processes could enable more sustainable production through material savings. A survey conducted by Sculpteo revealed that 41% of the companies surveyed see additive manufacturing as a way of achieving their sustainability goals [4]. However, the studies examined indicate that the energy requirements of AM processes are negatively impacted by both raw material production and the AM system itself. The environmental sustainability of AM processes could be improved through the increased use of renewable energies and more energy-efficient process plants. If the material efficiency of the process can be improved, this will contribute to resource efficiency. Further studies are needed to better assess the sustainability of additive manufacturing processes. After all, additive manufacturing is a highly dynamic technology and the number of corresponding processes and machines is constantly growing. Furthermore, a great deal of process-specific expertise still needs to be built up before these technologies are fully competitive with traditional processes in industry. However, this also offers the opportunity to make the processes of raw material and component production more sustainable.

Further information on the topic of "Industrialization of additive manufacturing" can be found in the roadmap of the Coordination Office for Additive Manufacturing. Secure free expert knowledge now.

Event tip: EinDruck³ 2024 - Paths to digital and sustainable production

Would you like to know how you can reduce your company's ecological footprint and how additive manufacturing can help you do this? Then visit our EinDruck³ expert forum! Here you can find out more about environmentally friendly raw material sources and sustainable product life cycles. Our experts will also explain how industrial 3D printing can help to reduce CO ₂ emissions in production. Another focus will be on the topic of data acquisition and use in additive manufacturing.

Literature reference:

[1] DeBoer, B., Nguyen, N., Diba, F. et al. (2021) Additive, subtractive, and formative manufacturing of metal components: a life cycle assessment comparison. The International Journal of Advanced Manufacturing Technology, 155, 413-432

[2] Priarone, P., Catalano, A., Settineri, L. (2023) Additive manufacturing for the automotive industry: on the life-cycle environmental implications of material substitution and lightweighting trough re-design. Progress in Additive Manufacturing

[3] Liu, Z., Jiang, Q., Cong, W. et al. (2018) Comparative study for environmental performances of traditional manufacturing and directed energy deposition processes. International Journal of Environmental Science and Technology, 15, 2273-2282

[4] d'Orsetti, A. et al. (2022) The State of 3D Printing, 2022 Edition. Sculpteo

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