Additive manufacturing – sustainable by nature

Besides minimizing waste, additive manufacturing removes steps in the supply chain.
“You go directly from a digital design to a three-dimensional product. And, if you locate production close to where it’s needed, you can also cut down on the storage, packaging and transportation of parts,” Amelie Norrby says.

In the long term, Additive Manufacturing (AM) might play a significant role in reaching the United Nation’s Sustainable Development Goals, according to Eduard Hryha, researcher and project manager for the new Centre for Additive Manufacture – Metal (CAM2) at Chalmer’s University of Technology in Sweden.
“To reach the climate goals, we must make significant changes to the way we manufacture products. Additive manufacturing is one of those revolutionary methods.”

There are two fundamental aspects that define sustainable manufacturing: the actual manufacturing process and the impact of the product produced. Additive manufacturing has significant effects on both levels.

Reduction of production steps

When it comes to the manufacturing process, some of the sustainability advantages are obvious. In the “Powder Metallurgy – Intrinsically Sustainable” report, the Metal Powder Industries Federation compares the 17 manufacturing steps that are required to produce a truck gear using subtractive machining with the mere 6 that are required using a powder metal process – with each less step bringing a saving in energy consumption.

“Additive manufacturing is more sustainable because you only use exactly the material you need for the component, reducing waste to almost zero,” says Amelie Norrby an engineer who participated in the guitar project. “Any powder remaining in the printer can be recycled for the next project.”

As Amelie Norrby also pointed out, another major advantage is that the actual production can be undertaken locally; all you need to transport is powder. The printer can be placed at the customer site or very close by. This means that the number of transportations is reduced even more. Furthermore, additive manufacturing cuts down on material waste.

“When printing a component, approximately 95 percent of the powder you put into the process is used; the rest can be recycled in a new melt,” says Mikael Schuisky, Head of R&D and Operations at Sandvik Additive Manufacturing. “Compare that to traditional manufacturing where you start off with a chunk of material and reduce large amounts of chips.”

Higher resource efficiency

Even though the chips from traditional manufacturing are collected and sent for recycling, the carbon footprint is substantially higher, due to heavier transportation and a much larger amount of material to recycle. This has a significant energy impact. Melting steel in the efficient scrap-based electric Sandvik steel mill requires approximately 500 kWh per ton steel. This is significant when compared to the resource efficiency of powder technologies and additive manufacturing.

“Additive manufacturing is presently used mostly for producing components with complex designs or those benefitting from being light in weight. Weight reduction is a constant key issue for the aerospace industry, driven both by fuel cost and carbon footprint”, says Mikael Schuisky. “The same is true for cars and trucks, and everything else that moves. Each kilogram of weight loss on an airplane saves 3,000 US dollars per year in fuel.”

Amelie Norrby chose to work in additive manufacturing because she thinks it’s one of the most disruptive technologies to have emerged in recent years. She also thinks its inherent sustainability makes it an important technology for the future. “It is just fantastic and a great advantage to be able to be part of the ongoing additive transformation journey. What we do and develop today will most likely have a huge impact in the future, not least from a sustainability perspective”, she says.