Rapid formation of high-performance lunar regolith composite via combined mold pressing and thermocuring processing with low content of resin-based additives

Establishing lunar bases is pivotal for furthering lunar research and propelling deep space exploration. Lunar regolith based in-site construction is identified as the most feasible method for lunar structures. In addition, the reliance on Earth-Moon transportation, the energy required for lunar regolith manufacturing and the quality of the fabricated products are key factors in choosing a suitable forming method. This study proposes a novel way for in-site lunar regolith construction by utilizing a small amount of resin-based binding material and a combined processing method of molding and thermosetting. A specific thermosetting resin is developed to achieve fully solidification of the mixed material at lunar daytime temperatures of approximately 120 °C, addressing the high energy consumption associated with the sintering process. Mold pressing is used to provide the rapid pre-forming of mixed materials and greatly reduce the proportion of additives. The binder additions ranging from 5 wt% to 1 wt% were investigated. It was found that the formed part with a binder proportion of 2 wt% could achieve a compressive strength exceeding 26 MPa and the low thermal conductivity of about 0.371 W/(m·K). The proposed method has advantages of high in-situ utilization rate, low-energy consumption and rapid formation rate, enabling efficient forming of high performance lunar regolith structure and providing feasibility for future lunar construction projects.