Processing and Characterization of Carbon Fiber Reinforced Ceramic Nanocomposites

Mechanical properties, physical properties, and microstructure of the carbon fibers reinforced ceramic matrix nanocomposites have been investigated. The matrix was derived from the pyrolysis of SILACERM™ NCP-200 with the addition of nanosize SiC powder. Slurry infiltration was adopted for the process and multi-impregnation was applied to densify the composites. In order to further enhance the density of the composites, the heat treatment over 1800°C was used. Mechanical properties of the composites with and without the addition of nanosize SiC were compared; three-point bending was employed to evaluate the influence of the addition of nanosize ceramic powder on the mechanical property of the composites. Void formation during pyrolysis process was studied, and the effect of void on the mechanical property was also investigated. Microstructure of the fracture surface under three-point bending test was examined by SEM; the role of nanosize ceramic powder on the fracture propagation during three-point bending test was also been examined. Moreover, X-ray was used to study the evolution of crystalline phase at different temperatures.