ANALYTICAL MODEL OF THE HIGH STRAIN-RATE EXPANSION OF A HOLLOW CYLINDER

A theoretical model of the high strain-rate deformation of a hollow cylinder is presented. The model takes into account the stress-strain characteristics of the material, its density and its yield strength. It has been assumed that the material obtains its initial kinetic energy instantaneously, and that part of this energy is expended in plastic deformation whilst the rest remains as net energy. This approach enables the calculation of the time of the process and the maximal expansion of the cylinder. The calculations have been performed for a range of strain rate from 787. 4 s** minus **1 up to 7874. 0 s** minus **1 with aluminum 6061-T6 being chosen as the model material. The calculated time of the expansion process varies from 6 mu s to 32 mu s for strain rates from 787. 4 s** minus **1 to 7874. 0 s**M**I**N****1 respectively. Comparison of the results obtained from the theoretical model with experimental results published by other authors has also been made.