Hafnium carbide (HfC) modified carbon/carbon (HfC-C/C) composites were prepared by impregnating carbon felts with a saturated HfOCl2·8H2O ethanol solution and heat treating at 600 ℃ to form HfO2/C composites that were then densified with pyrocarbon by chemical vapor infiltration and graphitized at 2 100 ℃ to convert HfO2 into HfC. The HfC-C/C composites as rocket throats were ablated at 7 MPa and around 3 200 ℃ for 3 s by an experimental solid rocket motor. Results showed that the HfC-C/C composites with HfC contents more than 5.7 mass% had a stable period with a constant ablation rate and the duration of this period increased with HfC content. The overall ablation rate was decreased by 25. 2 and 49. 6% for the composites having 5. 7 and 8.7 mass% HfC respectively as compared with the composite with 2. 5 mass% HfC.%将炭毡浸渍于饱和的HfOCI2·8 H2O乙醇溶液中,经600℃热处理形成HfO2/C复合材料,然后采用热梯度化学气相沉积工艺在2100℃进行致密化和石墨化处理使HfO2转化为HfC而得到碳化铪(HfC)改性、整体炭毡增强的炭/炭(HfC-C/C)复合材料整体喉衬.利用小型固体火箭发动机试车台装置,在7MPa、3200℃烧蚀3s以测定HfC含量对喉衬烧蚀性能的影响.结果表明,HfC质量分数为5.7％的HfC-C/C喉衬线烧蚀率减小了25.2％；HfC质量分数为8.7％的HfC-C/C喉衬线烧蚀率减小了49.6％.同时,当HfC质量分数为5.7％时,HfC-C/C喉衬出现了以恒定线烧蚀率为特征的稳态烧蚀阶段,且该阶段的持续时间随HfC含量的增加而增加.
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