T-strain effects in kinked interfacial fracture of bonded composites

摘要

Strain-based criteria are employed to predict fracture initiation behavior in bi-material cracked components. Two versions of the maximum tangential strain criterion are developed theoretically for the case of a crack existing at the interface of two dissimilar isotropic elastic solids to predict kinking angle and the mixed-mode interfacial fracture toughness. The first version (MTSN) is developed based on the singular strain fields while the second version (EMTSN) takes into account the effects of the first non-singular strain term (T-strain) as well as the singular terms. The theoretical effect of T-strain on the calculation of the kinking angle and the mixed-mode interfacial fracture toughness is studied. Then, both MTSN and EMTSN criteria are examined by comparing theoretical predictions to the previously reported experimental results for the kinking angle and mixed-mode interfacial fracture toughness in different bonded composite specimens. It is found that considering T-strain can significantly improve the theoretical predictions of the experimental results provided by the maximum tangential strain criterion.