In deep drawing process planar anisotropy is found to be a major problem. A high planar anisotropy causes earing in the formed cup (formation of wavy edge at the top). In this paper anisotropic behavior of stainless steel sheet is studied for drawn rectangular, circular and octagonal shaped parts. Finite element based simulation software PAMSTAMP2G is used to simulate the forming of the octagonal deep drawn cup. It is well known that the blank shape and size greatly affects the strain distribution in deep drawing process. Earing is a major problem due to highly anisotropic behavior of the selected material. To optimize the initial blank shape to minimize earing, the flow of material was observed at various steps during the forming and accordingly blank shapes were modified. Four blank shapes were considered to minimize earing for the forming of octagonal product. Finally a circular blank was used for forming of the octagonal part which gave minimum earing. The thickness strain distribution for circular shaped blank is better as compared to other blank shapes.
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