Stress intensity factor interface comer

The choice of a failure criterion is obvious when interface-comer stresses are described by one real-valued, power-law singularity. In this case, a single interface-comer stress-intensity factor /sTa characterizes the magnitude of the stress state in the region of the interface comer. 

However, even this approach needs an additional characteristic length. Reddy and Guess proposed the use of the critical intensity factors of the interface comer stress for the prediction of the interfacial quality. The so-called dominance zone of the stress intensity factor must be larger than the plastic zone in this case. This is a reasonable assumption only for certain materials, e.g., ceramics and cleavage fracture of metals, but not for polymers. 

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