The First Metal 3D Printer Designed for Space is En Route to the ISS

Metal 3D printing will make life easier for astronauts

Plastic 3D printers have already been in use on the International Space Station (ISS) since its initial arrival in 2014. The printers have been aiding astronauts in replacing or fixing plastic components in the attempt to mitigate the challenge of delayed equipment deliveries in space.

However, not all items can be crafted from plastic… Besides, the logistical constraint issue will likely become more pressing on future Moon and Mars stations in the next few decades. Therefore, despite the need to still transport raw materials up into space, printing the part in space is still more efficient than transporting them fully assembled.

Gwenaëlle Aridon, Airbus Space Assembly lead engineer, says: “The metal 3D printer will bring new on-orbit manufacturing capabilities, including the possibility to produce load-bearing structural parts that are more resilient than a plastic equivalent. Astronauts will be able to directly manufacture tools such as wrenches or mounting interfaces that could connect several parts together. The flexibility and rapid availability of 3D printing will greatly improve astronauts’ autonomy.”

Challenges of Printing Metal in Space

While 3D printing has been mastered on Earth, printing metal in space poses its own unique technical hurdles. Sébastien Girault, a metal 3D printer system engineer at Airbus, elaborates on these challenges:

• The first challenge is size. On Earth, metal 3D printers occupy spacious laboratories, but for the ISS prototype, the printer had to be scaled down to the size of a washing machine. This miniaturisation was necessary in order to fit the printer inside the rack in the ISS’ Columbus Laboratory. “At this size, we can print parts with a volume of nine centimetres high and five centimetres wide,” Girault says.
• The second concern is safety, as the ISS must be shielded from the intense printing environment created by the laser and its heat. The printer has to be in a sealed metal box, akin to a safe. Since the melting point of metal alloys suitable for this process can exceed 1,200°C, a significant difference compared to the approximately 200°C melting point of plastic, drastic thermal control is required.
• Gravity management is also crucial, “which is why we chose wire-based printing technology. The wire is independent of gravity unlike the powder-based system, which always has to fall to the ground,” Girault says.

Moreover, whether it is plastic or metal, emitted fumes will have to be dealt with by filters and captured within the machine so that the air inside the ISS is not contaminated. “Safety and contamination are key drivers for us not only for the ISS, but for future use on the Moon,” Aridon says”.

Exploring Metal Printing in Microgravity

One of the questions that the team aims to address is the suitability of metal printing in a microgravity environment. The experiment involves utilizing two printers: the ‘flight model’ aboard the ISS and the ‘engineering model’ on Earth. Astronauts will produce four samples in space, which will later be returned to Earth for analysis. These same samples will be manufactured using the engineering model printer. “In order to evaluate the effects of microgravity, ESA and Danish Technical University will perform mechanical strength and bending tests and microstructural analysis on the parts made in space and compare them to the other specimens,” Girault explains.

Photo: Airbus

Aiming for the Moon

Metal 3D printing aboard the ISS aims to improve understanding of metal printing quality in space and offer valuable insights into operating such printers in orbit. Printing structural components in space is a crucial step in equipping humanity with the necessary technology required for a sustainable presence on the Moon.

“Increasing the level of maturity and automation of additive manufacturing in space could be a game changer for supporting life beyond Earth,” Aridon stresses. “Thinking beyond the ISS, the applications could be amazing. Imagine a metal printer using transformed regolith [moondust] or recycled materials to build a lunar base!”

The metal 3D printer was created by a collaboration involving Airbus Defence and Space, AddUp, Cranfield University, and Highftech Engineering, funded by the European Space Agency (ESA). The view expressed herein can in no way be taken to reflect the official opinion of the ESA.

Congratulations to AAIS member, AddUp, for being a member of consortium that developed this 3D printer!