Strengthening and 3D Printing of Magnesium-Silicate-Hydrate Binder for Martian Construction (2024-10)¶

Utilizing in situ materials through automated 3D additive manufacturing is crucial for future space construction, particularly for Mars. In this study, we attempted to use magnesium silicate hydrate (MSH) binders as a promising option, as the Martian mineral resources are rich in silica and magnesium, and MSH exhibits a high reactivity with CO2, which can be benefitted from the Martian atmosphere consisting of a high concentration of CO2, differing from Earth. This study aims to examine the strengthening and 3D printing of MSH binders formulated using a Martian regolith simulant (MGS-1) as fine aggregates, light-burned magnesium oxide, micro silica, and water. To further investigate the effects of carbonation on physical–mechanical properties, two different CO2 curing regimes were considered: (1) incubator with 20% CO2 concentration and (2) ambient air. The experimental characterization included rheological, chemical, and mechanical analyses. The testing results revealed that CO2 curing enhanced the strength of MSH binders, implying the promising role of CO2 in the Martian atmosphere. Furthermore, the relationship between the MSH mixture design and 3D printability was investigated, and key parameters for the optimal composition for successful printing were explored. Results, although limited to drawing definite conclusions at this stage, imply the potential feasibility of in situ resource utilization (ISRU)-based Martian construction.