Numerical Simulation of Effect of Methyltrichlorosilane Flux on Isothermal Chemical Vapor Infiltration Process of C/SiC Composites

A two‐dimensional axisymmetrical mathematical model for the isothermal chemical vapor infiltration process of C/SiC composites was developed. Transport phenomena of momentum, energy, and mass in conjunction with infiltration‐induced changes of preform structure were taken into account. The integrated model was implemented by the finite‐element method to simulate numerically the isothermal chemical vapor infiltration (ICVI) process of C/SiC composites at different methyltrichlorosilane (MTS) fluxes. The influence of MTS flux on concentration distribution and time‐dependent densification behaviors of C/SiC composites was studied in detail. Calculation results imply that MTS flux has an obvious influence on infiltration in micro‐pores and little influence on infiltration in macro‐pores. Increasing flux will lead to an evident acceleration for infiltration in micro‐pores. Moderate flux is preferable by a combination of both a relatively high infiltration rate and a relatively low fabrication cost. This model is helpful to understand the fundamentals of the ICVI process for the fabrication of C/SiC composites.