Sintering of Chang’e-5 high-fidelity lunar soil simulant for providing high-strength materials for lunar base construction

Lunar soil simulants (LSSs) are terrestrial materials synthesized in order to mimic the aspects of lunar soil which is crucial to the emulating test technology for building a permanently manned lunar base. Here, we prepare a set of high-fidelity LSSs called by Beihang-3 (BH-3) through systematically studying the morphological, chemical composition, mineralogical, and crystallographic of lunar basalt fragments returned by Chang’e-5 (CE-5). BH-3, with a median particle size difference of less than 10 µm compared to CE-5 lunar soil, is composed of clinopyroxene, plagioclase, olivine, and ilmenite whose crystal structures match those of CE-5 lunar soil, exhibiting comparable Raman spectral characteristics. In addition, the oxide content of Si, Fe, Al, Ca, Ti, and Mg in BH-3 deviates by less than ±5% from the average composition of CE-5 samples. This compositional and structural similarity makes BH-3 a thermophysical-equivalent simulant, exhibiting heat-related properties analogous to those of CE-5 lunar soil. Furthermore, the compressive strength of sintered BH-3 specimens increases by 401% when the sintering temperature increases from 1100°C to 1175°C, while the porosity decreases by 17.3%. The compressive strength of sintered high-fidelity LSS is comparable to high-strength concrete used in Earth construction, making it sufficient to support in-situ lunar construction.