Iron-enhanced simulated lunar regolith sintered blocks: Preparation, sintering and mechanical properties

Abstract

Lunar surface constructions face a hostile service environment, the objective of this study is to develop a lunar base construction material with excellent mechanical properties and superior durability. Based on the abundant iron (Fe) resources on the moon, simulated lunar regolith sintered blocks (CUG-1A) with varying Fe additions (0–10 wt%) were prepared by pressureless sintering, and their sintering characteristics, phase compositions and mechanical performance before and after high-low temperature treatment were studied. The results show that the introduction of the Fe phase noticeably improve the sintering quality and increase the relative density. Furthermore, the Fe phase significantly fortified the sintered blocks, when the Fe addition reached at 10 wt%, the blocks could achieve a compressive strength of 150.92 MPa and a tensile strength of 21.01 MPa. The Fe phase's reinforcement could stem from the mechanisms of promoting sintering, crack deflection and Fe phase bridging. Meanwhile, the high-low temperature treatment does not cause any substantial alterations in the blocks' mechanical strength nor their failure modes. Lastly, large-sized sintered blocks with high dimensional regularity were produced through process optimization, providing a reference for the construction of lunar bases.