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Preparation and Performance of C/C-SiC Ceramic Matrix Composites

Carbon/carbon composite of various density were synthesized via chemical vapor infiltration process, and the sedimentary process of pyrolytic carbon were also researched. The density of the sample increased with the extension of growth time. Density change rate of the samples were various at different stages of the growth process, namely pyrolytic carbon of different densities formed at the different stages. It was found that pyrolytic carbon filled the pores of carbon fiber preform, which can help to relieve the interface stress between the fiber and the ceramic substrate. In order to improve the performance of the composite, SiC and ZrC ceramics were introduced into the carbon/carbon composite via polymer infiltration and pyrolysis (PIP) process. The ability of high temperature resistance and oxidation resistance of the composite were strengthened by the PIP process. The bending strength, tensile strength and compressive strength were also increased with the extension of PIP cycle. The C/C-SiC-ZrC composites were obtain through this process, which are useful in various areas.