ICVI法制备C/SiC复合材料构件的数值模拟

根据C/ SiC 复合材料的结构特点及等温化学气相浸渗法的工艺特点, 建立了C/ SiC 复合材料ICVI 致密化过程的数学模型, 并将该模型应用于C/ SiC 复合材料构件制备过程的数值模拟中。利用有限单元法, 对航空发动机用C/ SiC 复合材料小喉衬的ICVI 致密化行为进行了数值计算和分析。为了验证计算结果, 设计并进行了相应的对比实验, 对致密化后的喉衬构件进行了密度测量和CT 断层扫描无损检测。实验结果与模拟结果呈现出相同的变化规律并且两者之间偏差较小, 表明本文作者所建立的模型可以很好地描述C/ SiC 复合材料的ICVI 过程。利用该数学模型, 计算了ICVI 过程中喉衬构件的密度分布及其演变规律, 为ICVI 法制备C/ SiC 复合材料构件的进一步研究打下基础, 对ICVI 工艺的优化具有一定的指导意义。 

Numerical simulation for isothermal chemical vaporinf iltration of C/ SiC composites component

A two-dimensional axisymmetric model for the densification behavior of C/SiC composites in isothermal chemical vapor infiltration was developed according to the structural feature of C/SiC composites and the physicochemical phenomena of the isothermal chemical vapor infiltration process. A mathematical model was proposed to characterize the densification behavior of a small scale thruster liner component of C/SiC composites for a rocket engine by the finite element method. The density was measured and X-ray CT was inspected in order to validate the model. The analogical regularities represented by the calculation results and the experimental data show that the model developed in this article is reasonable and feasible to characterize the densification behavior of C/SiC composites in ICVI process. The calculated results, such as distribution and evolution of porosity and density of thruster liner component, lay the foundation of further research and optimization of ICVI process for fabrication of C/SiC composites components.