A novel mixed‐mode brittle fracture criterion for crack growth path prediction under static and fatigue loading

Abstract

AbstractIn this paper, in order to predict the crack growth direction and fracture load under mixed modes I and II loading, a new criterion is proposed. For this purpose, after reviewing existing criteria, an effective stress is defined so as to include the influential stress components in fracture and exclude insignificant ones. Moreover, investigations show that most criteria predict a certain angle of fracture in pure mode II independent of material properties, although the experimental results are noticeably different for various materials. To solve this problem, effects of the ratio of fracture toughness for pure mode II to that of pure mode I are considered by defining a new material parameter. To verify the suggested criterion, after characterization of the newly defined material parameter, the predicted values using this criterion for the mixed‐mode conditions are computed. The predicted results show a good agreement with the experimental results.