Numerical simulation method for elastic-plastic dynamic response for hypervelocity impact phenomena

This study presents a time-dependent numerical method for impact in planar or cylindrical symmetry. We use Eulerian finite-difference scheme, Tilloston's Metallic Equation of state, von Mises Yield criterion, for calculating the large deformation of elastic-plastic high velocity impact. Failure, cavitation and melting of solids are accounted for. The present model treats the formation and evolution of a crater, the deformation of the projectile and the deformation and dynamical response of the target. A two-stage gas gun was employed to experimentally study the phenomena of hypervelocity impact. Good agreement is obtained between the present computational results and craters obtained in experiments of polyethylene/aluminium impacts. The relation of crater shape and penetration depth to dynamic parameters of the projectile and the target is discussed. The Multi Purpose Graphics System (MPGS) is used to describe the calculation results with color graphics.