Dynamic Fracture Characterization of Cantilever Structure Specimens with V-Notch Tips

The dynamic fracture behavior of polymethyl methacrylate (PMMA) cantilever structure specimens with different notch angles under low-speed impact is studied using the digital array high-speed imaging system. First, dynamic caustic patterns at the notch tip and the propagating crack tip, respectively, are recorded. Then, the evolution of the stress intensity factor (SIF) and the crack propagation velocity are calculated, which are illustrated in detail based on the stress wave. Finally, the effect of notch angle on fracture behavior is analyzed, and the microscopic characterizations of the fracture surface are described. The results play an important role in evaluating the dynamic fracture properties of cantilever structures.