MICROSTRUCTURE AND OXIDATION RESISTANCE OF SIC COATED CARBON-CARBON COMPOSITES VIA PRESSURELESS REACTION SINTERING

The effects of processing parameters on the microstructure and oxidati on resistance of silicon carbide (SiC) coated carbon-carbon (C-C) comp osites were investigated. C-C composites were made from plain woven ca rbon cloths and phenolic derived carbon matrices in the laboratory. Pr essureless reaction sintering has been used to apply SiC coating to C- C composites using epoxy resin and silicon powder as the precursor. Re sults showed that the oxidation resistance of C-C composites was enhan ced by coating with SiC. The pressureless reaction sintering process e xhibits good processability. beta-SiC was formed after heat treatment at 1800 degrees C and the alpha-SiC formed after heat treatment at 220 0 degrees C. The SiC coated C-C composites exhibit good oxidation resi stance at 1000 degrees C for 100 h under the test conditions.