Lunar Regolith as a Construction Material via In-Situ Thermite Reactions

In-situ manufacturing and construction techniques must be researched and optimized to enable the sustainable development of lunar infrastructure. In this work, we present multi-parameter optimization of a novel, dual fuel, regolith based in-situ thermite material for additive manufacturing and construction on the Moon. Magnesium and aluminum are used as metal fuels and lunar regolith simulant is used as an oxidizer in thermite reactions to sinter metallic regolith samples. The loading of magnesium, aluminum, and simulant was varied across samples, as well as the simulant particle size to determine their effects on the combustion and final product. The combustion and physical properties of the materials were experimentally measured to demonstrate applicability to lunar AM and construction. The high reactivity of magnesium enabled reliable self-propagation, but excess magnesium created weak, porous products. Aluminum was less reactive and was not able to reliably cause a thermite reaction to self propagate, but did enabled greater mechanical strength of the products. The use of both metals in regolith-based thermite is demonstrated to provide reaction reliability and improved physical characteristics after combustion. The application to Martian regolith is discussed with sustainability implications and future technology developments.