Influence of material properties on the performance of blast-loaded steel plates with pre-cut defects

Experimental and numerical investigations are carried out to determine how thin steel plates with pre-cut defects behave under blast loading. The defects considered in this study are represented by four square holes, symmetrically distributed around the centre of the target plates. The target plates were manufactured from two types of steel, i.e., a dual-phase medium strength steel and a high-strength martensitic steel. A shock tube facility was used to expose the plates to blast-like loading conditions. The experiments showed that both the blast resistance and the corresponding fracture mode changed with material properties. Numerical simulations were performed using the finite element code LS-DYNA, where the numerical results were found to be in good agreement with the experimental data in predicting the ductile fracture during the blast-structure interaction. The numerical simulations confirmed that significant work hardening will distribute the plasticity throughout the plate material during deformation, while limited work hardening will tend to localize the plasticity that results in earlier fracture.