CVI法制备2D C/C复合材料

The preparation of 2D C/C composites by chemical vapor infiltration

采用预制体直接加热模式的CVI工艺在25.5h内制备出24mm厚的2DC/C复合材料,分析了该工艺快速致密的机理,并观察和测试了材料的微观结构和力学性能。结果表明:该工艺能在较短时间内制备出结构均匀、力学性能较好的C/C复合材料,是一种制备C/C复合材料较为理想的工艺。其快速致密机理可认为:自由基磁吸引作用、自由基电沉积作用和自由基脱氢聚合三个方面。

2D C/C composites of 24 mm thickness were prepared by chemical vapor infiltration (CVI) for 25.5 h using liquefied petroleum gas as carbon source in a cold furnace, where 2D preforms were heated by passing electrical current through them. The rapid densification mechanism of the process was investigated, and microstructures of the materials were observed. Results show that CVI can be used to prepare C/C composites with uniform structure and good mechanical properties in a shorter time. The mechanism of rapid densification by CVI includes magnetic attraction of radicals, electric deposition of radicals, and dehydrogenation and aggregation of radicals.