A Novel Ceramic-Liquid Alloy Lattice Metastructure for Thermal Protection in Aerospace Applications

Extreme thermal shock in space exploration poses a critical threat to orbital spacecraft, as conventional thermal protection structures cannot concurrently resist concentrated thermal effects under shock and ensure efficient heat dissipation during routine operation. Herein, we propose a ceramic-liquid alloy composite lattice metastructure as an integrated architecture achieved through the synergistic hybridization of a rigid ceramic framework and a functional liquid alloy, with its performance validated via integrated numerical and experimental studies. The thermal properties of the metastructure are “programmed” by designing two key geometric parameters: the fineness ratio of the lattice and the volume fraction of the liquid alloy. Through this approach, a significant enhancement in heat dissipation efficiency was achieved, along with a broadly tunable equivalent thermal conductivity ranging from 0.437 to 6.209 W/(m·K). The liquid alloy's thermotropic phase change dynamically regulates the metastructure's heat transfer behavior, thereby actively absorbing heat to suppress temperature elevation and enhance thermal shock resistance. Meanwhile, its innovative cross-sectional design mitigates thermal stress concentration at the ceramic-liquid alloy interface, achieving a 50% reduction in interfacial thermal stress and remarkably improving extreme temperature tolerance. This work provides a novel strategy for high-performance thermal protection and holds great promise for revolutionizing spacecraft thermal protection system design to advance space exploration reliability.