An analysis of the forging processes for 6061 aluminum-alloy wheels

The metal forming processes of aluminum-alloy wheel forging at elevated temperatures are analyzed by the finite element method. A coupled thermo-mechanical model for the analysis of plastic deformation and heat transfer is adapted in the finite element formulation. In order to consider the strain-rate effects on material properties and the flow stress dependence on temperatures, the rigid visco-plasticity is applied to the simulation. Several process conditions were applied to the simulation such as punch speed, rim thickness, and the depth of die cavity. Experiment for a simplified small-scale model is carried out and compared with the simulation in terms of forging load to verify the validity of the formulation adapted in this study. Then, various processes with full-scale model for a 6061 aluminum-alloy wheel are simulated. Material flow, pressure distributions exerted on the die wall, temperature distributions and forging loads are summarized as basic data for process design and selection of a proper press equipment.