5. Conclusions
This study investigates the possibility of combining the CAE technology and DOE study for determining the
adequate press motion design for the forging process design using servo-press machine. On the basis of the results
of the DOE study for pulley upsetting simulation, it is possible to effectively predict the adequate condition of
press motion necessary for reducing the forming load. Experimental results showed similar tendency of the
forming load variation as that of the simulation result. However, there are still some substantial differences
between the predicted and measured forming loads. For the precision spur gear forging, the motion condition for
complete filling of the tooth region, in order to minimize the forming load, could be predicted using the DOE study
of 3-dimensional numerical simulations under various motion conditions.
On the basis of the results obtained, it can be realized that the process design method introduced in this study could
provide useful information on the forging process using servo-press with flexible motion definition. For more
practical use to satisfy the industrial needs, the following issues should be addressed in the future:
(1) Collecting accurate flow stress data considering the effects of temperature and strain rate.
(2) Improving the accuracy of non-isothermal simulation handling for cold and warm forging processes.
(3) Improving the robustness of the DOE study to handle complex press motion definition.
(4) Improving the simulation efficiency for reducing the total calculation time required for multiple simulations.