【摘要】 采用高温熔渗反应（RMI）工艺制备了密度为2.50 g/cm³的C/C-ZrC-TiC-SiC复合材料，并通过氧乙炔火焰烧蚀实验系统研究其高温耐烧蚀性能。在热流密度为4.2 MW/m²条件下烧蚀30 s后，材料的线烧蚀率和质量烧蚀率分别为0.06600 mm/s和0.00411 g/s。烧蚀过程中，中心区因温度极高，SiO₂大量蒸发及剥蚀消耗，表面形成以ZrO₂、ZrTiO₄和TiO₂为主的Zr-Ti-O氧化层。过渡区中，熔融SiO₂相渗入并封堵基体孔隙，与Zr-Ti-O氧化物共同形成连续致密的氧化膜覆盖于表面，有效阻隔氧气侵入，减缓基体进一步氧化侵蚀。而在边缘区，剥落的SiO₂颗粒和晶须在表面堆积，形成致密的SiO₂保护层，进一步提高了复合材料的抗烧蚀性能。更多还原

【Abstract】 The C/C-ZrC-TiC-SiC composites with a density of 2.50 g/cm³ were fabricated by the high-temperature reactive melt infiltration （RMI） method.The high-temperature ablation resistance of C/C-ZrC-TiC-SiC composites was investigated by oxyacetylene flame ablation test.After 30 s ablation under the flame with a heat of 4.2 MW/m²,the linear and mass ablation rates are 0.06600 mm/s and 0.00411 g/s,respectively.Due to the highest temperature at the ablation center,the continuous consuming and denudation of SiO₂ resulted in the formation of a Zr-Ti-O （ZrTiO₄,TiO₂） oxide layer on the central surface.In the transition area,the residual SiO₂ melt sealed the pores and combined with Zr-Ti-O oxides to form a continuous protective film covering the surface,which can effectively prevent the further erosion of the inner matrix.Moreover,the scoured SiO₂ particles and whiskers from ablation center are deposited on the surface of ablation brim,forming a continuous SiO₂ layer to further enhance the ablation resistance of the composites.更多还原