Abstract: This study addresses the sealing challenges in planetary soil sampling. It aims to design a radial compression sealing device using a shape memory alloy (SMA) triggered by temperature changes. The device ensures sample integrity and reduces the need for high axial force, optimizing the sealing process. A microscopic leakage model, based on Roth’s law, is used to evaluate the impact of structural and external factors on leakage rates. Two SMA sheet configurations are analyzed, with simulations showing that the sharp-angle design enhances sealing reliability. The device uses polyimide heating films for resistive heating, achieving sealing by radially compressing the canister. Theoretical leakage rates are predicted, and the energy consumption is assessed through thermal simulations. When the SMA sheet’s diameter deviation from the inner wall is under 0.20mm, the leakage rate reaches 10^-6Pa·m³/s. Tests show an average compression stress of 160MPa, with measured leakage rates consistent with predictions. The total energy consumption is 2137.7J, demonstrating the device's high sealing efficiency for orbital sample transfer. The SMA-based device effectively seals without requiring significant axial force. The sharp-angle configuration particularly enhances performance. This device offers a reliable, energy-efficient solution for planetary sample orbit transfer sealing with broad potential applications.

Key words: star soil sampling, sealing device, shape memory alloy, leakage rate model, sealing leakage rate