Rigid-Plastic Finite Element Simulation of Peening Process with Plastically Deforming Shot

Abstract

To simulate not only plastic deformation of a workpiece but also that of a shot in a peening process, the effect of the interaction between the shot and workpiece in the collision is included in the dynamic rigid-plastic finite element method. In the formulation, the equilibrium equations of nodal forces are solved simultaneously with velocity boundary conditions at the interface between the workpiece and shot for sliding and non-sliding contacts. Axi-symmetric plastic deformation in peening of a circular workpiece with a single shot is computed. The calculated shapes of the workpieces and the shots are in good agreement with the experimental ones for plasticine workpieces and shots. It is shown that almost no plastic deformation of the shot occurs under actual shot-peening conditions for steel workpieces when the flow stress ratio of the shot to the workpiece is larger than two.