T-strain effects in kinked interfacial fracture of bonded composites

• Published in: Theoretical and applied fracture mechanics Vol. 104; p. 102381
• Main Author: Mirsayar, M.M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.12.2019; Elsevier BV
• Subjects: Crack initiation; Criteria; Fracture mechanics; Fracture toughness; Interface crack; Interfacial fracture toughness; Kinking; Kinking angle; Strain-based criteria; T-strain; Interface crack; Kinking angle; Interfacial fracture toughness; Strain-based criteria; T-strain
• ISSN: 0167-8442; 1872-7638
• DOI: 10.1016/j.tafmec.2019.102381

[Display omitted] •Developing strain-based criteria for fracture initiation at the interface cracks.•Theoretical effects of T-strain on kinking angle of interface cracks.•Theoretical effects of T-strain on mixed-mode interfacial fracture toughness.•Comparing the test data with the MTSN and EMTSN predictions.•Superior predictions by EMTSN criterion showing significant effects of T-strain. 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.