Efforts to establish a permanent human presence on the Moon are moving forward. One of the major projects aiming to accomplish this feat is, for example, NASA’s Artemis program. As you can imagine, this goal brings with it countless challenges, one of them being the logistics of building with materials from Earth. Since the program’s launch, there have been several proposals, and today we present the most recent. This is a study from Concordia University in Canada that proposes using regolith as a raw material for building on the Moon.
The scientific article presenting this solution was recently published in the arXiv repository. In it, scientists explore the manufacture of a 3D printing material based on PEEK (polyetheretherketone) reinforced with a lunar regolith simulant. This could be used to produce parts, tools and even infrastructure directly on the Moon, taking advantage of local resources.
Example of the filament with some thickness inconsistencies. (Credit: arXiv)
When considering 3D printing on the Moon, one must consider factors like temperature, radiation and low gravity. Previous attempts to combine regolith with PEEK had failed due to extrusion complications. The harder regolith particles increased the torque (moment of force) in the extruder and limited the mineral content to a maximum of 30%. Furthermore, the parts were more porous, which reduced tensile strength and increased fragility.
To address these challenges, the team led by Mohammad Azami introduced two key innovations. A new twin-screw extruder design capable of more homogeneously mixing PEEK with up to 50% regolith simulant, and the use of a special PEKK (polyether-ketone-ketone) interlayer “raft,” deposited with a second nozzle, helped reduce warping and adhesion problems on the build plate.
After optimizing the process, the researchers annealed the parts at 300°C. This step helped improve some mechanical properties, although the benefits were limited in mixtures with more than 40% regolith. The results showed that the incorporation of the lunar material increased the stiffness of the parts by up to 41% and reduced warping during printing, resulting in greater dimensional accuracy. However, tensile strength decreased from 107 MPa for pure PEEK to 90 MPa for parts with 40% regolith and to about 70 MPa for those with 50%. Additionally, fragility increased, with a lower capacity for elongation before breaking.
Representative examples of printed replicas, ranging from pure PEEK to PEEK with 50% regolith by weight.
Thus, the research concludes that the most balanced mix is around 60% PEEK and 40% regolith, which saves terrestrial material without excessively compromising mechanical properties. With these results, the scientists establish a practical benchmark for future additive manufacturing projects in space.
The researchers point out that this is just a first step. Their next goal will be to test these techniques in simulated lunar environments, including vacuum, low gravity, extreme thermal cycles, and radiation. They also plan to experiment with other polymers and scale the process to large-format robotic printing systems capable of manufacturing complete structures directly on the lunar surface, such as habitats. If you are interested in learning more about the project, you can consult the scientific publication HERE.
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*Cover Photo: representations of the material with different percentages of regolith. Credits, arXiv