Thermal Property Engineering of Lunar Regolith via Spark Plasma Sintering

Abstract

The extreme logistical challenges of Lunar exploration and habitation encourage in situ resource utilisation. Spark Plasma Sintering is a technique capable of rapidly consolidating Lunar regolith without additives, leveraging the vacuum conditions of the Lunar surface. The manufactured components could be used for thermal energy storage, construction, or precision engineering, applications that are sensitive to how the thermal properties vary across the Lunar temperature range of -120°C to 120°C. Understanding how the sintering process influences the thermal properties is essential for optimal design and performance. This study investigates the effects of SPS process parameters on the coefficient of thermal expansion, heat capacity, and thermal conductivity of sintered regolith simulants. Both a mare and a highland simulant were sintered to expand the current body of knowledge with this data and with evaluation of the implications for in situ utilisation. The findings show that sintering temperature is the most influential factor affecting all three thermal parameters. Variations in thermal conductivity and heat capacity with density suggest that engineering trade-offs are necessary to optimise the thermal performance of thermal storage systems, structural materials, and precision components.