Dynamics of the Oblique Impact and Ricochet of Nondeforming Spheres against Thin Plates

The dynamics of the impact of hard spheres against mild steel and aluminum alloy plates has been investigated by using an analytical model of impact dynamics to interpret experimental data. The analytical model assumes rigid body response of the sphere to forces on the sphere expressed as a quadratic function of the speed of impact and a factor equal to the presented area of contact between the sphere and plate. The dependence of the force on speed is determined by an empirical correlation of the constants in the quadratic function experimental measurements of the residual speed for impacts at normal incidence. The failure of the plates is modeled by the removal of resisting force over predetermined areas once critical depths of penetration have been exceeded.