化学气相渗C／SiC材料结构与性能的研究

采用碳布层叠然后用化学气相渗方法制备了Ｃ／ＳｉＣ复合材料，这种材料纤维与基体间的界面是决策材料力学行为的重要因素，带有热解碳作为界面层的Ｃ／ＳｉＣ材料，在断裂进表现出大范围的脱粘，纤维与周围的基体不同发生断裂，有大量的纤维拨出，断口类似毛刷，无界央层材料表现为脆性平面断口，裂纹直接通过纤维和基体向前扩展，没有发生脱粘。

THE MICROSTRUCTURE AND MECHANICAL BEHAVIOR OF C/SiC COMPOSITES PREPARED BY CVI

C/SiC composites have been fabricated by using layered fabrics of carbon fibers and then densi-fied with SiC matrix deposited by CVI process. In such composites, the nature of the fiber-matrix interface isobviously a key factor in determing mechenical behavior.C/SiC composites with pyrolytic carbon interfaciallayers exhibit extensive debonding of the interface,resulting in the fracture of the fiber and the surroundingmatrix separately in different locations. This is accompanied by substantial apparent pullout of the fibers fromthe matrix,as suggested the brushlike fracture surface. In the absence of a fiber coating,composite with poortoughness will be fractured by the propagation of a single,near-planar cracks that pass through the matrixand fiber without interfacial debonding.