Effects of material properties on the subsequent collision in collision of three spheres

Abstract

In this study, the influence of material properties on the occurrence of subsequent collision in the direct central collision of three identical spheres was investigated by FEA (finite element analysis). A sphere with impact speed is made to collide with the two rested spheres. Based on the material properties of the A5052 (aluminum), the density, Young's modulus and yield stress were changed with half and double, respectively. The occurrence of subsequent collision was judged by the sign of the coefficient of restitution. It was found that the critical subsequent collision speed, which is the boundary of occurrence of subsequent collision, shifted to the lower speed side as the density and Young's modulus increased and, shifted to the higher speed side as the yield stress increased. That is, the subsequent collision occurs at a lower speed with higher density and Young's modulus and lower yield stress. The change of the critical subsequent collision speed due to the yield stress was the largest and, Young's modulus also showed the same degree of change, while the change due to the density was small.