Railgun experiment and computer simulation of hypervelocity impact of lexan projectile on aluminum target

Results of hypervelocity impact tests at an electromagnetic launcher with plasma armature are described. The tests were performed with a thick duralumin disk of 80–100 mm diameter and of 40 mm height impacted by a lexan cylinder of 1.5–3 g mass. The projectile velocity amounted to 4–5.5 km/s. The launcher operational characteristics are described. In the tests, various configurations of the target fracture were obtained including cratering and spall cracks, disks and cones. The computer simulations were accomplished by means of a 2D axisymmetrical SPH code using interparticle contact algorithms. In these algorithms, stresses and velocity at the contact points of Lagrangian particles are computed by the linear Riemann solver. For description of material failure, a model based on a threshold stress criterion was used. The main features of material distribution and target fracture are reproduced in simulations.