Evolution and characterization of cyclic thermal shock-induced thermomechanical damage in oxide/oxide ceramics matrix composites

Abstract

Thermal shock is a typical loading case for high temperature components in turbines. The ceramic matrix composites become attractive for their high temperature behavior. However, their low heat conductivity makes thermal shock damage a typical damage mechanism for the turbine application. In the present paper, microstructural evolutions of the oxide/oxide ceramic matrix composite under thermal shock are studied experimentally. The mechanical behavior is related to the thermal shock temperature and cycles. The thermomechanical damage is characterized by degradation of the macroscopic elastic modulus. A thermal shock damage model is introduced based on the continuum damage mechanics principle, which can describe monotonic as well as cyclic thermal shock damage processes.