1986 Volume 94 Issue 1088 Pages 409-414
The oxidation resistance of C-SiC-B4C composite materials was determined in air and compared with that of C-B4C composites. Powder mixtures of raw coke and SiC-B4C (42:58 in weight) was ground, compacted and baked in Ar gas at 2000°C. The oxidation resistance at 800°C was improved remarkably by more than 5vol% addition of SiC-B4C. Thus, the weight loss of the composites made from the ground powder containing 30vol% SiC-B4C was 0.2, 0.6 and 6% after 1000°C-20h, 1200°C-5h and 1300°C-5h heating respectively, whereas for C-B4C composites, 6 and 30% weight loss were recorded after 1000°C-20h and 1200°C-5h heating respectively. X-ray diffraction analysis and IR spectroscopy showed that the specimens were coated with a liquid film of B2O3- or SiO2-B2O3 glass in air.
