中文摘要：

采用反应熔渗法（reactive melt infiltration,RMI）制备ZrC改性多孔C/C复合材料,研究不同孔隙度的C/C多孔体在熔渗过程中的增密行为和渗Zr后的相组成及微观形貌,探寻具有最佳熔渗效果的C/C多孔体,并研究所得C/C-ZrC复合材料在不同温度下的氧乙炔焰烧蚀行为。结果表明,随C/C多孔体密度增加,C/C-ZrC复合材料的密度降低;其中密度为1.40 g/cm3的多孔体熔渗效果最佳,开孔隙率由熔渗前的28.2%降低到6.6%。;熔渗的Zr液易与网胎层处的炭纤维和基体炭反应,生成的ZrC陶瓷相主要分布在原网胎层位置。择取原始密度为1.40 g/cm3的C/C多孔体熔渗后进行60 s的氧乙炔焰烧蚀实验,在3 000℃下的线烧蚀率和质量烧蚀率分别为0.003 3 mm/s和0.004 2 g/s,在2 500℃下的线烧蚀率和质量烧蚀率分别为0.008 0 mm/s和0.009 0 g/s,C/C-ZrC复合材料在3 000℃下的抗烧蚀性能明显优于2 500℃下的抗烧蚀性能。

英文摘要：

C/C-ZrC composites were fabricated by reactive melt infiltration（RMI）.The densification behaviors of melt Zr infiltrating into different preforms were studied,subsequently,the resulting phases and characteristics were observed.Furthermore,the as-prepared C/C-ZrC composites from the preform with the optimal infiltration effect were selected for ablation test,and the ablation behaviors of C/C-ZrC composites under different temperatures were also investigated.The results show that the density of C/C-ZrC composite decreases with increasing the preform density.The porous C/C composite with density of 1.40 g/cm3 owns the best infiltration effect with the porosity decrease from 28.2% to 6.6%.Molten Zr reacting with the fibers and substrate carbon of the fiber web layers forms ZrC ceramic phase at the site of fiber web layers.The C/C-ZrC composites obtained by infiltrating Zr into preform with initial density of 1.40 g/cm3 is selected for ablation test,after ablation for 60 s,the linear ablation rate and mass ablation rate at 3 000 ℃ are 0.0033 mm/s and 0.004 2 g/s,respectively,and those at 2500 ℃ are 0.0080 mm/s and 0.0090 g/s,respectively.Thus,the anti-ablation properties of C/C-ZrC at 3000 ℃ prove to be superior to those at 2 500 ℃.