Numerical investigations of constitutive tensile behaviour of materials and wrinkling of cold-rolled aluminium sheet when deep drawn through a Tractrix die

摘要

Deep drawing is an important metal working process used for making cup shaped articles at a fast rate. The drawability of sheet metal can be quantitatively estimated by the Limiting Drawing Ratio (LDR). An inverse finite element procedure is developed and clubbed with ABAQUS computer code for the determination of constitutive tensile behavior of materials. The proposed inverse technique is based on the miniature specimen experimental load versus, elongation curve. In this paper miniature tension tests are conducted on dumb bell shaped specimen made from Aluminum. By using the output of experimental miniature tension test, constitutive stress-strain curves are traced through inverse technique. The use of a Tractrix die enhances the limiting draw ratio as compared with that obtainable in a conventional drawing operation. Application of these dies, in most of the cases, eliminated the use of blank holder but it enhances the tendency of wrinkling in drawn products.