Anti-Ablation Behavior of C/C-SiC Composite in Re-entry Flight Environment:A Ground Simulation Study

We addressed the anti-ablation behavior of carbon/carbon-silicon carbide(C/C-SiC) composites in re-entry flight environment via ground simulation with the lab-built vacuum test-platform capable of creating plasma-jet flow-field.First,the temperature/velocity distributions of plasma beam from the jet-nozzle were calculated.Next,the temperature and velocity of plasma irradiation at the C/C-SiC surfaces were evaluated.Finally,the abrasive properties,including the microstructures,phase-structures and ablation-rate of ablated surfaces were investigated with scanning electron microscopy,energy dispersive spectroscopy,depth-gauge and electronic balance.Distinctive stagnation/transition/fringe ablated-regions,originated from different ablation mechanisms and ablation-rates,were observed.At stagnation ablated region,gasification had a major impact,resulting in the highest linear ablation-rate(0.0373 mm/s) and mass ablation-rate(0.0363 g/s).As the radial distance from stagnation region increased,the ablation-rate gradually decreased,because of a combination of oxidation and pyrolysis ablation-mechanisms.