Abstract
The dimensions of die and workpiece are changed continuously during loading, unloading, and ejecting stage. Finally, to predict precisely the dimension of forged part and get the die dimension for the net-shape components, the analysis of die and workpiece should be evaluated from the loading to ejecting. Therefore, the experimental and FEM analyses are performed to investigate the elastic characteristics at workpiece and die in the closed-die upsetting for ferrous material FE techniques are proposed to consider the unloading and ejecting stages and estimate more precisely the dimension of forged part and die. The dimensional changes fur the workpiece were evaluated quantatively during loading, unloading, and ejecting stages. The strains measured by the strain gages were compared with the estimated values by the FEM.