The influence of die geometry on the radial extrusion processes

Three variants of radial extrusion are analyzed by simulation work. Case I involves forcing a cylindrical billet against a flat die. In case II, the upper punch forces a billet against a stationary punch recessed in the lower die. In case III, both the upper and lower punches move together toward the center of the billet. Major process parameters are identified as the relative gap height and the die corner radius in constant relative deformation. The simulation work is performed by the rigid–plastic finite element method. The validity of the modeling and simulation work for this process is verified by comparison with experimental data in terms of forming load. The simulation results show good agreement with the experimental data. Based on the simulation results, the different process parameters are related to the different material flow. Due to various die motions, a certain pattern in the material flow is shown in each deformation case. The die geometry has a significant influence on the material flow into the flange gap.