INVESTIGATION ON THE OXIDIZATION KINETICS OF FELT BASE CARBON/CARBON COMPOSITES

In this paper,the kinetics of air oxidation of felt base carbon/carbon composites is investigated at different temperatures (773-1173 K). With the help of SEM, the micrographs of carbon/carbon composites are studied after different debrees of oxidation.The experimental results are shown that the oxidation rate of felt base carbon/carbon composites is constant at a given temperature.When the oxidation temperature is below and above 873k,the oxidation mechanisms of carbon/carbon composites are different and their apparent activation energies are 96 kJ/mol and 128 kJ/mol respectively.During the carbon/carbon composites oxidation initial stage,carbon felt is oxidized much more rapidly than matrix carbon,while during the carbon/carbon composites oxidation final stage,oxidation rate of matrix carbon increases.Otherwise,the oxidation rate of felt base carbon/carbon composites is influenced by the carbon/carbon composite surface reaction rate,the gas phase diffusion and the catalysts.