Evaluation of Crack Growth Criteria in Functionally Graded Polymer using Finite Element Metho

In this research first, different fracture criteria such as maximum tangential stress, maximum strain energy release rate, and minimum strain energy density are evaluated. Then, employing the interaction integral (M-integral) method in a functionally graded polymer, stress intensity factors for different directions of the crack orientation and mechanical properties are calculated. Applying the achieved results, the initiation angle of the crack is obtained by the various fracture criteria and compared with the experimental results existed in the papers. The results reveal that the predicted results of the maximum tangential stress and the minimum strain energy density criteria are close to each other but, the minimum strain energy density criterion has better accuracy. Finally, the calculated crack growth path is compared with the experimental results existed in the researches and the accuracy of the minimum strain energy density criterion is shown.