AN EVALUATION METHOD FOR INTERFACE TOUGHNESS OF ENVIRONMENTAL BARRIER COATINGS (EBCS) ON CERAMICS MATRIX COMPOSITES (CMCS)

摘要

Application of SiC fiber-reinforced SiC matrix composites (SiC/SiCs) in civil jet engines has been started and is expected to be expand. To use SiC/SiCs in combustion gas at high temperature of 1300-1400 °C, an environmental barrier coatings (EBCs) are needed to protect SiC/SiC from corrosion by water vapor. EBC and SiC/SiC substrate is subject to severe heat cycle from service temperature to ambient temperature and thus the thermomechanical durability is required as well as chemical environmental barrier properties. It is necessary to measure interface fracture toughness for the prediction of EBC life time and safe use of SiC/SiC.