The Simulation Of Cup Backward Extrusion Process

The backward extrusion process is a chief method to form the parts of nonferrous, iron and steel materials. It has been widely applied to the metal forming industry. Since 1980' s, the finite element method (FEM) as a numerical method has continuously widened its area of application in the metal forming process, and gradually changes the traditional ways in which people design and manufacture products. With FEM, the process of the metal flowing can be showed, and we can acquire forming state parameters easily and quickly, replaced the traditional estimate principle, achieving the scientific and economical product manufacturing.In this paper, the cup backward extrusion has been more thoroughly studied by the method combining numerical simulation with experiment. The 2D axisy-mmetry models of cup shell and its forming die have been build up, the theory of rigid-plastic FEM has been briefly described and the equation of penalty function FEM has been deduced; some problems for completing the FEM simulation process have been discussed; the cup backward extrusion processes of Al and CuCr have been simulated by the FEM, the metal deformation law has been revealed. A lot of information, including mesh distortion, velocity field, temperature field, equivalent stress field, equivalent strain field and load-stroke curve, has been got. The influence of frication factor and extrusion speed to load has been analyzed. In order to validate the credibility and validity of this simulation results and to analysis the characteristics of metal deformation Extrusion process, various experiments were designed and finished. To some degree, which shows the simulation results is reliable, and the cup shell was been extruded, which is signification for theory and production.