碳-高硅氧纤维增强C-SiC防热隔热一体化材料

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／CSiC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SiO2黏附在碳材料表面，对氧气有一定的阻挡遮蔽作用。密度为0．80g／cm^3的HSF／C材料，热导率为0．59W／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 thermal protective and heat-insulated integration material: carbon fibers and high-silica fibers reinforced C-SiC matrix composites

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 0.028mm/s.The better anti-ablation properties should attribute to SiO_2 formed by SiC oxidation holding up the flame further attack.The thermal conductivity of HSF/C with the density of 0.80g/cm~3 is 0.59W/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 16.7MPa.