碳/碳化硅复合材料静止环境下氧化行为模拟

碳/碳化硅(C/SiC)复合材料是应用于临近空间高超声速飞行器热防护的一种新型防热材料.国内外通过性能测试较多地研究了材料不同制备工艺对抗烧蚀性的影响,提出的抗烧蚀分析理论模型均基于液态氧化膜.而近期开展的C/SiC复合材料管式炉加热实验和试样微观形貌电镜表征显示:常压下,当温度低于1696 K时,C/SiC复合材料氧...

Simulation of C/SiC Composite Oxidation Behavior in Static Environment

Carbon/silicon carbon (C/SiC) composite is used as a new type of thermal protection material for near space hypersonic vehicles. The influence of preparation process on ablation resistance has been studied by performance experiments at home and abroad. The traditional theoretical models of ablation resistance are based on liquid oxide film. Recently, the heating experimental results in tubular furnace and microscopic morphology of sample characterized by electron microscopy show that the oxidation of C/SiC composite can form a porous solid oxide film under atmospheric pressure when the temperature is below 1 696 K. The pore characteristics of the outer oxide layer were evaluated by mercury intrusion method. Based on the gas diffusion behavior in the pores and reaction dynamics of oxidation, a new passive oxidation model of C/SiC composite was established. The predicted values of the model are in good agreement with the experimental results, which indicates that the new passive oxidation model has good prediction ability for the thickness of oxidation film and mass loss of material.