NUMERICAL-SIMULATION METHOD FOR ELASTIC-PLASTIC DYNAMIC-RESPONSE FOR HYPERVELOCITY IMPACT PHENOMENA

This study presents a time-dependent numerical method for impact in pl anar or cylindrical symmetry. We use Eulerian finite-difference scheme , Tilloston's Metallic Equation of state, von Mises Yield criterion, f or calculating the large deformation of elastic-plastic high velocity impact. Failure, cavitation and melting of solids are accounted for. T he present model treats the formation and evolution of a crater, the d eformation of the projectile and the deformation and dynamical respons e of the target. A two-stage gas gun was employed to experimentally st udy the phenomena of hypervelocity impact. Good agreement is obtained between the present computational results and craters obtained in expe riments of polyethylene/aluminium impacts. The relation of crater shap e and penetration depth to dynamic parameters of the projectile and th e target is discussed. The Multi Purpose Graphics System (MPGS) is use d to describe the calculation results with color graphics.