The prediction of damage subsequent to internal explosions has been a subject of interest for many years now. In order to be able to analyse the deformation and failure behaviour by numerical methods, experiments have been performed on steel plate material to derive the deformation and fracture behaviour. These experiments are performed for varying deformation rates to account for the influence of the strain rate in actual high-rate loaded structures. The flow stress of the material is examined as a function of plastic strain and strain rate. High-speed photography is applied to investigate the necking behaviour at high strain rates. The fracture behaviour of the plate material is examined by testing a number of notched specimens with different notch radii at various strain rates. The influence of the notch radius, and therefore the hydrostatic stress, becomes evident from these experiments. Failure strains decrease strongly with decreasing notch radius; however the strain rate has negligible influence on the fracture strain. Modelling these experiments using the strain-rate-dependent flow stress derived from the tensile tests results in fairly good agreement with the experimental results. The ductile damage is accounted for using the Rice and Tracey fracture model. Predictions of failure cannot be made so accurate, as the failure mechanism is not described very well. Investigations on the micromechanical behaviour of fracture must reveal the shortcomings of the failure analysis.
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