Authors: Abbas Hosseini Mehran Kadkhodayan
Publish Date: 2013/11/26
Volume: 71, Issue: 1-4, Pages: 337-355
Abstract
In deep drawing process the blank holder plays a key role in adjustment of metal flow into the die cavity Moreover the quality of drawn parts is extremely affected by this flow There are two methods of treating the blank holder in deep drawing and its simulation One is blank holder force BHF and the other is blank holder gap BHG defined as the fixed distance between the blank holder and the die surface In previous studies a large number of experimental techniques have been used to study BHF however the amount of theoretical and numerical simulation work to study BHG is insufficient In the present study the concept of BHG profile ie variation of BHG over punch stroke is introduced and it is shown that a properly selected BHG profile can improve the section thickness of formed part and result in the drawing of deeper parts Here two methods for the optimization of BHG profile are devised ie the local optimization and the global optimization methods In the first approach the best BHG in each punch step is determined and finally the local optimized BHG profile is achieved In the second method however the empirical model for the prediction of final minimum section thickness in terms of BHG profile is obtained using design of experiments and neural networks In the next stage the proposed model is implanted into a simulated annealing optimization procedure to identify a proper BHG profile that can produce the desired blank thickness Afterward the BHG profile approach is applied to a variety of initial thicknesses blank diameters and materials in order to examine the robustness of method In this paper ABAQUS finite element package is used to gather finite element FE data and several experiments are performed to verify the FE results
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