Determination of mixed-mode dynamic stress intensity factors in a fast curving fracture test using a laser caustic method.

Abstract

In order to investigate the mechanism governing elastodynamic crack curving, a series of fast curving fracture tests were carried out. In the present experiments, high-speed photographs of the caustic patterns for dynamically curving cracks were taken by a laser caustic method which can be quickly synchronized to the initiation of brittle fracture event. The mixed-mode dynamic stress intensity factors were evaluated on the basis of a theory of tics for mixed-mode fast running cracks, which was developed by some of the authors. It found that the magnitude of the mode II stress. intensity factor is closely related to the dynamic crack curving.