Martian rock-metal composite shows potential of 3D printing on Mars

A little Martian dust appears to go a long way. A small amount of simulated crushed Martian rock mixed with a titanium alloy resulted in a strong high-performance material in a 3D-printing process that could one day be used on Mars to make tools or rocket parts.

Materials were developed by Washington State University researchers with as little as 5%, and up to 100%, Martian regolith, a black powdery substance meant to mimic the rocky, inorganic material found on the surface of Mars.

While parts made with 5% Martian regolith were strong, 100% regolith parts proved brittle and cracked easily. But even high-Martian content materials would be useful in making coatings to protect equipment from rust or radiation damage, said Amit Bandyopadhyay, an engineer at Washington State and the corresponding author on a paper published in the International Journal of Applied Ceramic Technology. The research was supported by the U.S. National Science Foundation.

"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 Bandyopadhyay.

Bringing materials into space can be extremely expensive. Anything that can be made in space, or on a planet, would save weight and money.

For the study, Bandyopadhyay and 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 to more than 2,000 degrees Celsius (3,632 F). The melted mix of Martian regolith-ceramic and metal material flowed onto a moving platform that allowed the researchers to create different sizes and shapes. After the material cooled, they tested it for strength and durability.

The ceramic material made from 100% Martian rock dust cracked as it cooled but, as Bandyopadhyay pointed out, it could still make good coatings for radiation shields, as cracks do not matter in that context. The mixture with 5% regolith did not crack or bubble and exhibited better properties than the titanium alloy alone. The results mean that the mixture could be used to make lightweight pieces that could still bear heavy loads.