炭/炭复合材料新型热梯度制备工艺(英文)

• 作 者: Shameel Farhan 李克智 郭领军
• 机 构: 西北工业大学材料学院,西北工业大学材料学院,西北工业大学材料学院 陕西西安710072,陕西西安710072,陕西西安710072
• 出 处: 新型炭材料
• 发表日期: 2007年03期
• 关键词: 预制体 炭/炭复合材料 炭毡 热梯度 化学气相渗透 致密化 纤维体积含量 烧蚀性能 炭纤维 材料性能

对传统的热梯度化学气相渗透工艺进行了改进。把高热导率(55W/(m.℃))的48k炭纤维束穿入针刺炭毡预制体中心。利用炭纤维束和炭毡预制体热导率(0.15W/(m.℃))的差异,在预制体内部产生热梯度。在900℃～1200℃下,天然气首先在预制体中心的48k炭纤维处热解,致密化沿径向由中心向外部推进,67h后材料的密度达1.778g/cm3。研究了炉内输入电压、电阻、致密化时间、沉积层位置等工艺参数对材料性能的影响。通过偏光显微镜和扫描电子显微镜研究了基体热解碳的微观结构,并对炭纤维体积含量为10%的炭/炭试样进行了烧蚀性能测试。

The traditional thermal gradient chemical vapor infiltration process has been improved. The 48 k charcoal fiber bundles with high thermal conductivity (55 W / (m. ° C.)) were inserted into the center of the needled carbon felt preform. Using the difference in thermal conductivity (0.15 W / (m. ° C.)) of the carbon fiber bundles and the carbon felt preform, a thermal gradient is generated inside the preform. Natural gas was first pyrolyzed at 48k carbon fiber in the center of the preform at 900-1200 ° C. The densification proceeded radially from the center to the outside. After 67 hours, the density of the material reached 1.778g / cm3. The effects of process parameters such as input voltage, resistance, densification time and deposited layer position on the material properties were studied. The microstructure of pyrolytic carbon was studied by polarized light microscope and scanning electron microscope. The ablation performance of carbon / carbon samples with carbon fiber content of 10% was tested.