Measurement of dynamic fracture toughness and failure behavior for explosive mock materials

Abstract

In this work, a pre-cracked semi-circular shaped explosive simulant was loaded using a split Hopkinson pressure bar (SHPB). A high-speed camera was used to capture the deformation and fracture process of the specimen in situ. The digital images were processed using the digital image correlation (DIC) method. Next, full displacement and strain fields were obtained. The displacement vector field shows that the specimen fractured under tensile stress action. The strain field can be used to predict the crack propagation. Results show that the method of combined DIC and SHPB is effective to study the dynamic deformation and fracture behavior of explosive simulants. In addition, the specimen was loaded using a drop weight. The fracture toughness of the specimen was preliminary measured.

Keywords

digital image correlation / polymer bonded explosive simulant / split Hopkinson pressure bar (SHPB) / semicircular bending test / deformation / fracture toughness

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Higher Education Press and Springer-Verlag Berlin Heidelberg