Dynamic Fracture Process during Three-Point- Bending Impact on Polymethyl-Methacrylate Beams

Abstract

Dynamic fracture process in polymethyl-methacrylate (PMMA) beams have been investigated during the three-point- bending impact tests at different imapct velocites, conducted in a drop-weight impact tower instrument. The impact-induced crack initiation and propagation have been recorded with a high- speed camera, to determine the instantaneous fracture length and crack velocity during impact process. The beam deformation and displacement fields were extracted and analyzed by using the digital image correlation (DIC) thechnique during the impact. The impact loading history has been recorded with a load cell attached to the dropping weight. The whole experimental study is a suitable technique to determine the influence of the impact velocites (impact energy) on the dynamic fracture initation and propagation at different crack speeds.