摘要
C/C复合材料因其特异性能在航空航天、武器装备等领域得到了广泛应用.但其制备过程中致密化周期很长导致成本居高不下,限制了C/C复合材料在众多领域的应用.采用定向气流温度梯度气相渗透(TG-CVI)快速致密化方法制备盘状C/C复合材料,并对其致密化行为和致密化工艺进行研究.结果表明:定向气流TG-CVI法能有效抑制气相沉积过程中C/C复合材料表面"结壳"现象,实现盘状C/C复合材料的逐层快速致密化,是制备盘状C/C复合材料较为理想的工艺.在1 080℃下,只需沉积67 h,C/C复合材料的密度就可达到1.8 g/cm~3,热解碳结构全部为粗糙层结构(RL).
C/C composites have been widely used in aerospace, weaponry and other fields for their peculiar properties. However, in the process of their preparation, the cycle of densification is very long and the cost is high, which limits the application of C/C composites in many fields. A directed-flow temperature gradient chemical vapor infiltration(TG-CVI) rapid densification method was used to prepare disc-like C/C composites and their densification behavior and densification technics were studied. The result showed that the directed-flow TG-CVI method could effectively inhibit the phenomenon of "crusting" on the surface of C/C composite during vapor deposition and realize-by-layer rapid densification of discoid C/C composites. It would be an ideal process for the preparation of discoid C/C composites. At 1 080 ℃, only 67 h would be needed to make the density of C/C composite to reach 1.8 g/cm~3, and the structure of the pyrolytic carbon would entirely be rough-layer structure(RL).
引文
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