Oxidation behavior of C/C-SiC composites in open atmosphere

Abstract

C/C and C/C-SiC composites plates were directly exposed with the flame of oxyacetylene gas welding to see the effect of temperature (>1000°C) in open atmosphere. Duration of exposure time was increased to measure the weight loss and ultimate performance of composites. Weight loss, maximum tensile stress and compressive stress tests were performed to find the behavior of C/C-SiC composites after the exposure of oxyacetylene gas flame in open atmosphere. The amount of the heat transferred to the base material depends upon the distance, the torch is held from the materials. The results show that the weight loss increases with increase of exposure time. Which clearly indicates that the excess amount of carbon is oxidized with the oxygen to form the carbon mono-oxide. The matrix materials undergo pyrolysis reactions within short periods which generate volatiles and leave behind a porous skeleton of carbon fibres. Therefore, ultimate performance of C/C and C/C-SiC composites was reduced with increase of exposure times. However, 2D C/C composites give lower values than the C/C-SiC composites.