The extensive use of adhesive bonding has placed significant research interest in development of fracture prediction tools for bi-material interface problems. The focus of this research project is to address this issue for a specific joint problem. Good agreement between numerical and experimental results has been obtained. This has been achieved through the development of a comprehensive transformative numerical code in ANSYS. Fundamental hypotheses have been presented in order to employ relevant singular elements on crack tip. Element type and size effects on results are discussed. The fracture criterion examined for modeling progressive growth of sharp crack in E27/steel interface is the maximum principal stress. Recent laboratory findings have been used for Mode-I fracture data of CT specimen. Analyses have been implemented by modeling both linear elastic and nonlinear hardening behavior of E27 according to standard tensile test data for this epoxy. These results have been discussed in details. Near tip analyses under mode-I loading predict a constant distance from tip that minimum mode mixity (ψ) corresponding to pure shearing can be seen. Also a simple brittle failure predicting approach, based on near tip linear elastic interfacial fracture mechanics (LEIFM), is demonstrated and proposed to the specific joint problem. Final model affords to elaborate acceptable failure conditions for bi-material interface cracked structures.

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