Kinetics of Self‐Crack‐Healing of Alumina/Silicon Carbide Composite Including Oxygen Partial Pressure Effect

Abstract

Self‐crack‐healing behavior under a combustion gas atmosphere with a low oxygen partial pressure , , is important for actualizing ceramic gas turbines, but to date only self‐crack‐healing behavior in air has been investigated. In this study, we investigated crack‐healing behaviors at 1273–1773 K under several levels of . Crack‐healing in atmospheres with gave rise to the complete strength recovery of cracked specimens, resulting from passive oxidation. Based on the obtained results, the kinetics for strength recovery by self‐crack‐healing was expressed as a function of healing temperature, T H (K), and (Pa). The strength recovery rate for complete crack‐healing, v H (s −1 ), could be expressed as image Using this rate equation, one can evaluate the healing time for complete strength recovery under combustion gas in a gas turbine.