烧蚀过程中C/C复合材料的结构演变

摘要: 利用SEM和TEM考察了3D C/C复合材料在电弧加热器上烧蚀后的材料表层显微组织结构变化。发现炭纤维和基体炭中的石墨微晶经过烧蚀后都得到了明显的发展。在距烧蚀表面几个纳米的深度范围内形成了高度取向的带状石墨织构，同时，在带状织构中间也形成了许多孔洞和缝隙。在距烧蚀表面几个微米的深度形成了卷曲柱状结构，在这些柱状结构周围有许多缺陷。在纤维和基体炭的界面区域，靠近纤维一侧形成了带状织构，且织构间的缝隙变大。

Abstract: Textural changes of a 3D carbon/carbon composite after ablation in an arc jet heater were examined under SEM and TEM. It was shown that obvious enlargement of graphite crystallites was generally observed for both carbon fibers and matrix. A highly ordered graphitic ribbon-like texture was developed within a few nanometers of the ablated surface of the carbon fibers with gaps between the ribbons. Crystallites in the form of a round hollow column were present in the matrix of the ablated surface. A ribbon like texture in the interface region near the side of the carbon fibers was observed.