A two-dimensional model for densification behaviour of C/SiC composites in isothermal chemical vapour infiltration

摘要

A two-dimensional model was developed according to infiltration-induced structural changes in C/SiC composites and physicochemical phenomena involved in isothermal chemical vapour infiltration (ICVI) process. The mathematical model was implemented to simulate the densification behaviour of the C/SiC component of a small-scale thruster liner for rocket engine. The calculated results show that infiltration efficiency is high at first and then decreases dramatically, which is in agreement with the corresponding experimental results. The correspondence between calculated results and experimental data implied that this mathematical model is reasonable and feasible for characterizing the densification behaviour of C/SiC composites in the ICVI process. The dependence of densification behaviour of C/SiC composites on infiltration temperature has also been investigated. Calculation results show that the densification rate increases while density uniformity of overall composites decreases evidently with elevated temperature.