Degradation of Silicon Carbide in Combustion Gas Flow at High Temperature and High Speed

The effects of various basic factors of combustion gas flow conditions on the degradation behavior of silicon carbide (SiC) have been experimentally clarified. The degradation of SiC in combustion gas flow was expressed in terms of weight loss. The weight loss depended markedly on the water vapor partial pressure, becoming larger with increasing water vapor partial pressure. The effect of oxygen partial pressure on weight loss was small, and the weight loss decreased with increasing oxygen partial pressure. By considering the effects of the partial pressures of water vapor and oxygen, the gas temperature, the pressure and the gas flow velocity did not have such a significant effect on the weight loss in the given range of test conditions. Based on experimental results, it was clarified that water vapor partial pressure is the major factor causing the degradation of SiC.