【摘要】 通过液态浸渍结合热梯度化学气相渗透(TCVI)制备了碳化铪含量为2.5%(质量分数)的C/C(HfC-C/C)复合材料。利用split Hopkinson pressure bar(SHPB)装置,对HfC-C/C复合材料进行了不同载荷冲击损伤,采用氧乙炔火焰烧蚀法测定了复合材料的烧蚀性能,结合扫描电镜分析了冲击损伤对HfC-C/C复合材料烧蚀性能的影响。结果表明:动态冲击损伤对HfC-C/C复合材料线烧蚀率的影响不显著,而其质量烧蚀率随冲击载荷的增加而增加,且冲击载荷对HfC-C/C复合材料质量烧蚀率的影响存在有一个阈值,超过此值,材料的质量烧蚀率显著增加。更多还原

【Abstract】 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.更多还原