Study Highlights Sustainability of Metal Additive Manufacturing

The ecological issues of additive manufacturing have been highlighted for several years and the sustainable aspect of the technology has become a real advantage. There are many examples: in architecture where less concrete is used, in the consumer goods market, or even in the manufacture of lithium batteries.

A recently published report now provides specific information on the durability of metal 3D printing throughout the value chain. Specifically, this analysis addresses key questions of sustainability in additive manufacturing compared to traditional methods, such as the factors that ensure a lower carbon footprint and how users can achieve their personal or corporate sustainability goals. CO2 thanks to additive manufacturing.

Looking back over the last few decades, the steady increase in CO2 in our atmosphere and the underlying consequences for people, nature and the planet are truly worrying. To help companies directly reduce their carbon footprint, additive manufacturing is increasingly coming into play throughout the production cycle.

To assess sustainability, AMPOWER has designed a calculator to assess the CO2 footprint of different technologies. There is quantitative evidence that CO2 emissions from powder bed fusionare significantly lower than those of milling.

This is because weight-optimized constructions can be produced by 3D printing and the material and energy inputs are therefore lower. Powder binding , which produces low emissions throughout its process from 3D printing to debinding, has achieved surprisingly good results.

Metal 3D printing for sustainability

An important point to consider when it comes to sustainability is the different types of energy used in production. For example, other industrial processes and manufacturing technologies – casting for example – generate heat and therefore direct CO2 emissions by burning fossil fuels. In contrast, metal additive manufacturing only uses electrical energy, which means that this required energy results in a different amount of carbon emissions.

Looking at the entire metal additive manufacturing value chain, sustainability starts with material requirements, i.e. the exact amount of raw material needed. Regarding the subsequent recycling of the material, the proportion of recycled material is relatively high, which is further supported by new processes for the production of 100% recyclable metal powders.

With regard to the possibility of “production on demand”, a considerable part of CO2 emissions can be saved thanks to this method, since it minimizes the storage capacities required as well as the transport needs. 

Also, in terms of sustainability in metal production, increased product efficiency should be considered. Optimizing weight and performance increases the efficiency of parts such as turbines, hydraulic systems, airplanes or even cars. This results in energy savings over the lifetime of the additively manufactured part.

Which technology is the most sustainable?

According to the AMPOWER report, it is very difficult to say which type of production has the lowest carbon emissions. Why ? Because it depends a lot on the alloy group used as well as the part geometry. Simply put, this means that complex geometries have the lowest carbon footprint when 3D printed, while simple parts are the most durable when milled.

With regard to the durability calculator and taking the example of an aircraft part, the weight is often directly related to the fuel required and therefore to the CO2 emissions generated. If weight can be reduced, so can the resulting fuel consumption.

In aviation, an annual value of 2,500 liters of kerosene per kilogram of weight saved is calculated. If we assume that an aircraft part has a lifespan of around 20 years, this means that up to 50,000 liters of kerosene or 126,000 kilograms of CO2 can be saved per kilogram of weight saved per aircraft.