Ablation behaviors of Carbon/Carbon composites after impact damage

The HfC modified C/C (HfC-C/C) composites were prepared by thermal gradient chemical vapour infiltration process after infused hafnium liquid. The virgin composites were pre-damage under different impact loadings using a split Hopkinson pressure bar (SHPB), and the ablation resistance of HfC-C/C composites was determined by an oxyacetylene flame with high velocity gas. The effect of impact damage on HfC-C/C composites was discussed by combined the SEM analysis. Results showed that under different impact loadings the values of linear ablation rates made little difference, while the mass ablation rates increased with the impact load increased for the composites. It is shown that the mass ablation rates increased drastically after an impact loading threshold is reached.