Design and Test Verification of Energy Absorption Material in the Soft Landing Gear for Tianwen-1 Mars Probe

The landing gear is a key component for soft-landing on Mars, which should use high energy-absorption and excellent thermal stability material to absorb the impact energy of Mars probe. The energy absorption pull rods made by directionally solidified twinning-induced plasticity (TWIP) were utilized for the soft landing gears of Mars lander. The mechanical behavior and microstructure evolution of TWIP steel were investigated. The results show that TWIP steel can sustain the high plasticity of 600 MPa ultimate true stress and 72% true strain. The landing dynamic simulation and experiment results of soft-landing gear drop testes demonstrate that that Mars landing system is able to adapt to the complex topography conditions because of the high energy absorption ability of pull rods.