Model for prediction of matrix microstructure for carbon/carbon composites prepared by forced flow-thermal gradient CVI Original Research Article

A model has been developed to predict the microstructure of the carbon matrix deposited during forced flow-thermal gradient chemical vapor infiltration (FCVI). This method employs previous thermodynamic-microstructure and densification models to determine conditions throughout the preform as a function of time. The model was verified by comparison with samples prepared over a range of deposition temperatures, reagent concentrations and flow rates. The model also showed that it should be possible to deposit a matrix of uniformly high thermal conductivity onto conventional size carbon fibers, as well as small diameter, low cost, high thermal conductivity carbon whiskers.