Fracture resistance of silicon carbide composites using various notched specimens

Nozawa, Takashi; Tanigawa, Hiroyasu; Park, J.-S.*; Koyama, Akira*

SiC/SiC composites are promising candidate materials for various energy industries. One of key issues for their practical application is to develop design basis of quasi-ductile composites. Understanding the crack propagation behavior is therefore essential. For this purpose, determining a fracture resistances undoubtedly important and this paper aims to evaluate this using various types of notched specimens. With the preliminary analysis by the authors, a new methodology to determine the fracture resistance has been developed based on the non-linear fracture mechanics, separately discussing the effect of irreversible energies. By adopting this method for nano-infiltration transient-eutectic-phase sintered (NITE) SiC/SiC composites, several key findings were obtained: (1) notch insensitivity, (2) no significant size effect, and (3) superior crack tolerance.