Sustainability 4.0: will Additive Manufacturing make it?.

By Greta D’Angelo, PhD, and Federico Fioretto

First of Two Articles

Sustainability is at risk of becoming just the latest buzzword in the world of business if it’s not a very practical way to run industries and transform the way in which production is made. This noble concept must instead be widely implemented and help transform the way in which we design, make, use and recycle stuff. To achieve such a bold objective sustainability must embed itself into every process of manufacturing industries. This means that it has to get along with technology’s evolution and accompany it in the right direction.

On the other hand, the very “trendy” 4.0 Industrial Revolution will not be a “revolution” at all if it does not integrate Sustainability into its core strategic elements. In that case it would just be “more of Industry 2.0” at best. Sustainability, as our readers know well, must stand upon the three legs of environmental stewardship, economic prosperity and social value creation. Therefore we will seek to identify such features into a typical Industry 4.0 technology: Additive Manufacturing (AM). Our aim is to help steer future developments of the technology in the right direction to boost sustainability of manufacturing and help Companies focus their investments towards the new industrial paradigm.

During the past few years we have heard a lot about this rising technology, more commonly known as 3D printing. This is deemed to become one of the technologies of the future and it is one of the macro trends of the Industry 4.0. While its potential unveils and the technology continues to develop, it is fundamental to identify and understand the relevant environmental impacts in order to grasp AM’s potential for a more sustainable industrial production. How AM will enable this is still unclear. Many of the studies are still focusing on material and energy consumption, which do not give a clear overview of the whole life cycle of the products made. However AM offers some resource efficiency benefits that, added to some specific design and production peculiarities leading to improved performance, have economic and environmental benefits.

We’ll leave aside for the moment the social value creation issue, which pertains more to the whole business and economic model than to the single production technology. Our focus will be on the environmental and economic impacts. Therefore the questions that we’ll ask is whether AM improves the environmental performance of a production process, e.g. reducing waste or energy consumption, and also the economic performance of the industry, with the generation of more wealth as an outcome. When it comes to AM and sustainability there are three main factors to take into account:

1. The product itself, from design to performance
2. The production process, with its input-output balance
3. The supply chain, from product order to delivery

We are aware that the above subdivision is a bit artificial and that it is not possible to disentangle completely, for instance, the product from the production process. Nonetheless, we prefer to deal with the chosen issue in this way for clarity reasons. There will be some overlaps that the reader will, we hope, forgive. The first two points will be discussed here, in Part I of this article, whilst the last one will be discussed in Part II together with an overview of potential business models for the integration of AM in the production.

1. The Product itself
   • It is widely accepted in the industrial world that designing products today needs to be a process taking into account awareness of many very different factors and stakeholders. Design impacts the whole value chain. Due to its additive nature, the combined capacity of AM to make more complex objects with integrated functions, preference for using fewer parts and less production stages can reduce the material flow and consequently the environmental impact of the product.
   • Points listed in 1.1 lead to a reduction of cost and increase of economic value even while making the same object, i.e. not considering smarter design allowed by the technology. Such improvements, of course, are larger when design is optimized for the technology.
   • The capability to optimize geometries and create lightweight components also reduces material consumption adding to the reduction in material flow and cost cutting of the above points.
   • The functional design allowed by this manufacturing process can lead to products with better performance. For example, a recent study from the Technical University of Denmark, published on Nature, demonstrated that bone-inspired structures applied to the wing of an aircraft can lead to better mechanical properties and up to 200 tons of fuel saved per year.
   • The additive nature of the technology and the rise of hybrid processes (additive + subtractive), i.e. Lasertec 65 3D hybrid from DMG MORI, encourage the use of AM for repair practice. This improves the environmental impact of products by extending their life cycles and lowering the energy and resources required for the manufacturing of brand new products.
   • The possibility of strict adherence to the individual customer’s needs with one-off productions at affordable costs can deliver excellent customer experience and performance, combined with the cost saving aspects discussed above. As an example, a full inventory of spare parts for machinery in a remote location would be unbearably costly, but the possibility to produce by AM the required parts at the moment of need makes a huge advantage, if not a possibility previously denied. The same principle can allow the production of objects specifically designed to fit a particular context or customers at a reasonable cost, something unthinkable with other processes, i.e. in the case of prosthetics and surgical implants.
2. Production process, inputs-outputs balance:
   • A variety of materials are being used in AM, from polymers to metals, whose form is dependent on the type of process in use. The majority of polymers can be recycled, e. parts made of Fused Deposition Modelling (FDM) can be re-melted and turned into new filament by using a scrap-to-filament converter device. For metals instead, it is estimated that 90 to 95 percent of the leftover powders used in-process can be re-used in the following productions.
   • AM allows to tackle one of the major problem of our planet: plastic waste in oceans and landfills. Numerous companies, i.e. Adidas to name one, started promoting many initiatives to collect the waste plastic and turn it into new products. Other initiatives are: Reflow and 3D-reprinter.
   • Amid all these positive aspects of AM regarding Sustainability, it is to be mentioned that Toxicological and environmental hazards from AM materials is an area that requires more research as it is not sufficiently understood at the moment. A number of studies reported the emission of harmful particles during the melting of ABS plastic, in desktop FDM printers. Liquid resins are also known to be mildly toxic and therefore their use is discouraged in non-ventilated
   • As a consequence of point 1.3 and 1.4, as in design of multi-component objects, there is a simpler integrated-assembly production with the consequent reduction of cost and quality risks of assembly of different components. A potential environmental advantage is to be evaluated, considering also the reduction of weight and volume of products due to improved strength-to-weight This will reflect in maybe minimal part on the product itself but its effect on the performance of objects down the value chain that are explored elsewhere in this article can be very significant (see point 1.4 for an example)
   • Logistics and transportation are another point where savings in energy inputs and emissions/outputs become interesting part of the Sustainability outcomes, either by environmental and economic impact (this point will be discussed more in depth in part II).
   • Research, although not yet conclusive and generalizable, hints to a better energy performance of AM compared to other production processes, something which has both an economic and an environmental impact. However, from a study of the University of California Berkeley, fellow researchers stated that “it cannot be categorically stated that 3D printing (AM) is more environmentally friendly than machining or vice versa” because the results are still dependent on many factors, for example: process and machine used, number of parts produced, process parameters and materials.

Already with the points highlighted above, there appears to be a remarkable value generated by the use of AM that can add to the Sustainability effort of manufacturing industries. To such value added, either in terms of cost saving/increased profits and lower environmental impact, we can sum some advantages that can be ascribed to the social:

• The fact that customers can have a better product experience due to more personalized products is one;
• The possibility to reach distant or isolated customers with products or services that before AM were unthinkable;
• The empowerment of customers to become “prosumers”, i.e. consumers who produce themselves at least part of the goods they need. This is most likely one of the more dramatic changes that AM will produce in the way our economy, with its production and consumption models are;
• Finally, we believe that there are whole new possibilities of employment and business, even at a small entrepreneurial scale, stemming from the technology. This generation of distributed economic power and entrepreneurial capacity can deliver a high social value.

In the second part of the article we will deal with the supply chain, including logistics aspects, and new business models to try to understand more wholly the potential of AM related to the three pillars of sustainability

This two-part Article is intended to be a stimulus to the constructive discussion about the implications of emerging technologies on the future impact of manufacturing. All interested professionals in the area of Sustainability are welcome to comment and add value to the discussion by contacting the authors at IT@esinitiative.com.

Greta D’Angelo is an industrial designer converted to the discipline of manufacturing engineering. She has a PhD in Additive Manufacturing from the Technology University of Denmark and has collaborated with numerous designers and universities, among which MIT and ETH Zürich. Greta is now a consultant in the area of Digitalization and Additive Manufacturing for the development of sustainable business models.