【摘要】 本文采用化学气相渗透(CVI)工艺制备了2D针刺预制体增强的C/C-SiC复合材料,并对材料密度、力学性能以及强粒子冲蚀下的烧蚀机理和破坏机制进行了分析。结果表明,C/C-SiC复合材料在强粒子冲蚀下的破坏机制主要为机械冲蚀和颗粒侵蚀,其次是冲蚀过程中伴随的少量氧化。材料内层间孔、束间孔以及针刺孔的存在加剧了C/C-SiC复合材料破坏。研究发现,通过改变预制体结构来实现材料力学性能的均衡,并提高材料密度以减少材料的孔隙率将成为该使用环境下的材料设计原则更多还原

【Abstract】 A 2D-C/C-SiC composite enhanced by needle-punching preform was densified by chemical vapor infiltration(CVI) technique, and its density, mechanical properties and the ablation and failure mechanisms under a high-energy particle erosion test were investigated in this work. The results show that the failure behavior of the composite under high-energy particle erosion were mainly controlled by the mechanical scour and the impacted particles eroding, and also controlled by the slight oxidation of the composite. The inter-layer, inter-bundle and needling pores in the C/C-SiC composite will aggravate the failure of the composite. It suggested that homogenizing the mechanical properties in different areas of the composite by changing the preform structure and reducing the porosity by increasing the material density would be two key design principles for the C/C-SiC composite operating in the high-energy particle erosion condition.更多还原