A DEVELOPED PROCESS FOR INCREASING DEEP DRAWABILITY OF RECTANGULAR METAL CUPS WITH EXTREME ASPECT RATIO: FINITE ELEMENT SIMULATION

Multi stage conventional deep drawing techniques have shown low productivity and high production cost especially for producing rectangular cups with extreme aspect ratio. The non-homogeneous materials flows due to irregular die cross section and contact conditions leads to localize thinning, wrinkle formation and finally fracture of the drawn parts. To overcome these problems a novel three stages deep drawing process with elliptical-conical die set have been proposed to replace the equivalent six stages of the conventional multi- stage process. A series of FE-analysis were carried out with an explicit elasto-plastic finite element code Abaqus 6.9 in order to conduct the virtual experiments for evaluating the new process capabilities and optimizing the process parameters for producing the rectangular cup with extreme aspect ratio. The results of analysis revealed that the present process successfully produce rectangular cups with aspect ratio of 5.11 in three drawing stages with three intermediate annealing and two trimming processes. The proposed process has shown superiority over the previous multi-stage conventional processes since three drawing stages have been eliminated for the equal aspect ratio