Impact of the milling time upon sintering behavior of Carbon Fiber Reinforced Silicon Carbide composite

Ceramic matrix composites are consider for special properties such as high tensile and flexural strength, low density and light weight. Preparation of raw materials have important impact upon properties of sintered composite. The aim of this work is to evaluate effect of the milling time on morphology, crystalline size and mean strain of raw materials. The powders mixture of 65.6wt.% of SiC powders, 10wt.% additive with 24.4wt.% carbon fibers were mixed by a planetary ball mill for 10 hours in steel cup and ethanol as the grinding media. During process 1 gr sample was taken every hour. Phase type, crystallite size and mean strain were obtained by X-ray diffraction pattern. In order to morphology identification scanning electron microscopy and field emission scanning electron microscopy were used. Results demonstrated that increasing milling time gave rise to the reduction of crystalline size, increasing of mean strain and damage on carbon fibers surface which had negative impact on sintered sample. Finally uniform mixture of powders and carbon fibers were produced.