Abstract: The oxidation properties of SiC sealed 3 D C/SiC composites were researched in this paper. The test results obtained in combustion environments showed that the weight losses of the composites were related to the pores and the microcracks in coating and matrix, where the pores produced a main effect on the results. The mechanical properties of C/SiC oxidized in combustion gas decreased less apparently than in dry air, which resulted from the low partial pressure of oxygen in the combustion atmosphere.

Key words: silicon carbide, compo sites, combust ion gas, oxidat ion