碳-高硅氧纤维增强C-SiC防热隔热一体化材料

A thermal protective and heat-insulated integration material:carbon fibers and high-silica fibers reinforced C-SiC matrix composites

制备了一种新型的防热隔热一体化材料-碳-高硅氧纤维增强 C-SiC 复合材料,沿厚度方向从抗烧蚀层渐次过渡到隔热层,其组成依次是致密 C/C-SiC,致密 C/C,多孔 C/C,通过界面处过渡到变密度多孔 HSF/C．这种材料既具有抗烧蚀性能又具有隔热性能．C/C-SiC 复合材料的烧蚀表面平滑,线烧蚀率只有0．028mm/s．烧蚀性能的提高得益于 SiC 颗粒原位氧化生成 SiO_2黏附在碳材料表面,对氧气有一定的阻挡遮蔽作用．密度为0．80 g/cm^3的 HSF/C 材料,热导率为0．59 W/mK．在碳纤维与高硅氧织物的界面处,针刺纤维与热解碳的结合良好,密度为1．69g/cm^3的 C-HSF/C 复合材料界面处的剪切强度达到16．7MPa．

A novel composite, carbon fibers and high-silica fibers reinforced carbon matrix and silicon carbide matrix （C-HSF/C-SiC）, was prepared. The material consisted of four layers, which were densified C/C-SiC, densified C/C, porous C/C and porous HSF/C. The two formers act as the heat-protective layers while the two latter the heat-insulated layers. The composite possesses a smooth ablation surface after an ablation test performed on an engine torch and the erosion rate is only 0.028 mm/s. The better anti-ablation properties should attribute to SiO2 formed by SiC oxidation holding up the flame further attack. The thermal conductivity of HSF/C with the density of 0.80 g/cm^3 is 0.59 W/mK, which has a good thermal insulation action. The needling fiber bundles and pyrocarbon have integrated tightly carbon fiber fabric and HSF fabric. The interfacial shear strength between the two fabics is 16.7 MPa.