Dynamic fracture behavior and coupled impact effect of as-cast W-Zr-Ti energetic structural material

This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique. The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior. The specimens exhibit violent chemical reaction during the fracture process under the impact loading, and the size distribution of their residual debris follows Rosin-Rammler model. The dynamic fracture toughness is obtained by the fitting of debris length scale, approximately 1.87 MPa·m^1/2. Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression, while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact. Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target, leading to the effective ignition of fuel tank. For the brittleness of as-cast W-Zr-Ti ESM, further study conducted bond-based peridynamic (BB-PD) C++ computational code to simulate its fracture behavior during penetration. The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment. This paper explores a novel as-cast metallic ESM, and provides an available numerical avenue to the simulation of brittle energetic fragment.