RESEARCH ON ELASTOPLASTIC NORMAL IMPACT OF STEEL SPHERES AGAINST A RIGID PLANE

The normal impacts of perfectly elastic and piecewise linear/power law hardening steel spheres against a rigid plane were studied using finite element methods (FEM). The results of FEM model agreed with those by Hertz theory for elastic impacts. The FEM results of the elastic collisions showed that the kinetic energy dissipated by stress wave propagation could be neglected. The results of elastoplastic impacts were compared with the results of Johnson’s and Thornton’s. When the impact velocity was larger than the critical velocity, the finite plastic deformation started and the coefficient of restitution could be proportional to in the elastoplastic impacts.