Washington State researchers add to out-of-this-world 3D printer materials

Scientists from Washington State University have discovered that a small amount of simulated crushed Martian dirt mixed with a titanium alloy made for a stronger, high-performance material for 3D printing that could help build a future on the Red Planet.

"In space, 3D printing is something that has to happen if we want to think of a manned mission because we really cannot carry everything from here," said Amit Bandyopadhyay, a professor at Washington State University's School of Mechanical and Materials Engineering. "And if we forgot something, we cannot come back to get it."

Bringing materials into space is extremely expensive.

As international space agencies like NASA continue to seek a permanent presence on the Moon and Mars, the use of raw resources available on-site to build structures and habitats is a long-time goal to reduce how much material future missions need to bring from Earth.

As a result, this could significantly reduce the launch mass and cost of future missions – so far as low as US$1,400 per kilogram (2.2 pounds) with the SpaceX Falcon Heavy rocket – and provide a more sustainable method of constructing housing and other structures on planetary bodies.

Parts made with 5% to 100% simulated Martian soil, the researchers at Washington State University found that while 5% proved strong, 100% proved brittle and cracked easily. Still, even high-Martian content materials would be useful in coatings to protect equipment from rust or radiation damage.

Bandyopadhyay first demonstrated the feasibility of this idea in 2011 when his team used 3D printing to manufacture parts from lunar soil for NASA. Since then, space agencies have embraced the technology, with the International Space Station even sporting its own 3D printer to manufacture needed supplies in orbit for experiments.

For the most recent study, Bandyopadhyay and his team used a powder-based 3D printer to mix the simulated Martian rock dust with a titanium alloy – a metal often used in space exploration for its strength and heat-resistant properties. As part of the process, a high-powered laser heated the materials over 2,000 degrees Celsius (3,632 degrees Fahrenheit).

Then, the melted mix flowed onto a platform that allowed the researchers to create their samples. Afterward, the team tested them for their strength and durability.

The ceramic material made from 100% Martian rock dust cracked as it cooled, but Bandyopadhyay pointed out it could still make good coatings for radiation shields as cracks do not matter in that context.

But a little Martian dust, at around 5%, not only did not crack or bubble but exhibited better properties than the titanium alloy alone, which meant it could be used to make lighter weight pieces that could still bear heavy loads.

"It gives you a better, higher strength and hardness material, so that can perform significantly better in some applications," Bandyopadhyay added.

This study is just the start, he said, and future research may yield better composites using different metals or 3D printing techniques.

"This establishes that it is possible, and maybe we should think in this direction because it's not just making plastic parts which are weak but metal-ceramic composite parts which are strong and can be used for any kind of structural parts," the research lead finished.