碳/碳复合材料等温化学气相渗透工艺模糊系统建模

等温化学气相渗透(chemical vapor infiltration，CVI)是制备陶瓷基和碳基复合材料重要的传统工艺，该工艺主要的不足之处是周期极长，因此，优化工艺参数、提高沉积效率是目前等温CVI工艺研究的重点。在实验样本的基础上，利用遗传算法来自动获取和优化模糊规则，从而建立了碳／碳复合材料等温CVI工艺模糊系统。通过系统对训练样本和测试样本的输出，可以看出：系统具有较高的精度和泛化能力。利用该系统，得到了沉积温度、纤维体积分数和沉积室压强等参数对等温CVI工艺的影响规律，对实际生产中CVI工艺的制定有指导意义。

FUZZY SYSTEM MODEL FOR ISOTHERMAL CHEMICAL VAPOR INFILTRATION PROCESS OF CARBON/CARBON COMPOSITES

Isothermal chemical vapor infiltration (CVI) is an important conventional technique for fabrication of ceramic and carbon matrix composites. The major disadvantage of isothermal CVI process is the extremely long processing time required. Therefore the key point of research on isothermal CVI technique is to optimize process parameters and to raise the deposition efficiency. Based on the experimental results, the fuzzy rules were automatically obtained and optimized by genetic algorithm, thus the fuzzy system for isothermal CVI of carbon/carbon composites was established. Through the analysis of the output of training and testing samples, we could draw a conclusion that this system is characterized by higher precision and good generalization ability. With the help of this system the regulation affecting infiltration temperature, fiber content and chamber pressure in isothermal CVI were analyzed. The results show that this system has a good instructive function for formulating of CVI processes in practical application.