短碳纤维增韧石英复合材料性能研究

A Study on Properties of Short Carbon Fiber Reinforced Silica Glass Matrix Composite

以短碳纤维为初始原料 ,采用溶胶—凝胶技术引入SiO2 组分 ,在一定的热压烧结制度下得到致密Cf/SiO2 复合材料 ;研究了其烧结条件、力学性能、线膨胀及烧蚀性能。实验表明 ,基体保持非晶态 ,可达到 99%的致密度 ;随碳纤维含量的增加 ,弯曲强度 (σf)无显著变化 ,断裂韧性 (KⅠC)先升后降 ;线膨胀系数随碳纤维含量增加而增加 ,该材料具有良好的抗热震及耐烧蚀性能。

Short carbon fiber reinforced silica glass matrix composites are manufactured under certain particular hot pressed conditions with sol-gel silica and short carbon fibers as raw materials. The sintering conditions, mechanical properties, linear expansion and ablation properties are studied. The matrix remains amorphous and full dense. With increment of carbon fiber content,flexural strength (σ f) is hardly changed, while fracture toughness (K Ⅰc) is up and then dropped down. It is demonstrated that the composite has excellent thermal shock and ablation resistance, and coefficient of linear expansion is increased with the adding of carbon fiber.