Further studies of the oblique impact of a hard sphere against a ductile solid

The impact of hardened steel spheres against ductile mild steel targets has been studied both theoretically and experimentally. It is shown that a relatively simple computer model based on the assumptions that the sphere is rigid and the target an ideal rigid-plastic solid provides a surprisingly successful explanation of the observed variation of crater volume and projectile energy loss with impact angle and velocity. This model also explains satisfactorily the measured rebound velocity for oblique impact, but cannot account for the finite rebound velocity observed under normal impact conditions. Rebound angles also are under-estimated.