Forging of polygonal discs using the dual stream functions

Calculation and estimation of the final workpiece dimensions and required load forming via analytical solutions are likely to take long time and even sometimes exact solutions may not be found. However, by using numerical methods, estimations with high accuracy and high speed would be made possible by reducing calculation and processing time, also lowering the labouring and therefore the product cost.In this study, the dual stream and so upper bound method have been used to investigate the metal flow and load requirements in open die forging of polygonal blocks. Due to extremely high speed of analysis, it enables to facilitate the automation of the process. The kinematically admissible velocity field was constructed for incompressible material. The forging load of a polygonal aluminium block, longitudinal flow and sideway spread and hence new dimensions were estimated within time of less than a second for one step deformation. Experiments were conducted using lead AA5454 and showed good correlation with the theoretical analysis of dual stream functions (DSF).