Response behavior of double layer tungsten fragments under detonation loading

Abstract

Under detonation loading, the prefabricated fragments in the warhead will be greatly deformed and even broken. In order to explore the model of deformation, the dynamic response of double-layer spherical tungsten fragments under detonation loading was studied. Firstly, a typical cylindrical warhead model was numerically simulated. The simulation model for the characteristic section only includes the quarter model for the double row fragments in the axial direction, in order to obtain the deformation response of the fragments under the detonation loading. The full-size 1/4 simulation model is designed to obtain the axial velocity distribution of the fragment. In the characteristic section, the charge diameter was used as the variable to simulate five charge sizes, and the fragment deformation law was obtained. In order to verify the correctness of the simulation, the warhead of 400 mm caliber was tested, and the flight speed of the fragment was measured. Some deformed fragments were obtained by soft recovery and their cross-section microstructure were analyzed by scanning electron microscope (SEM). The results show that the deformation of the inner layer of the double-layer spherical tungsten alloy fragment is more serious under the action of the internal explosion load, because it is squeezed by the internal explosion load and the outer layer fragment at the same time. The final dispersion velocities of the inner and outer fragments tend to be the same, and there is no significant difference in the distribution of fragments.