On the Effect of Through-Thickness Integration for the Blank Thickness and Ear Formation in Cup Drawing FE Analysis

Abstract

Various numerical parameters such as element size, mesh topology, element formulations effect the prediction accuracy of sheet metal forming simulations and wrong selection of these parameters can lead to inaccurate predictions. Therefore, selection of proper numerical parameters is crucial for obtaining of realistic results from finite element (FE) analyses. In the present work, influence of the number of through-thickness integration points from the numerical parameters was investigated on the cup drawing simulation. Highly anisotropic AA 2090-T3 aluminum alloy was selected as test material and the anisotropic behavior of the material was defined with Barlat 91 yield criterion. Firstly, cup drawing model was created with implicit code Marc and then FE analyses were performed with five, seven and nine layers to investigate the effect of number of through-thickness integration points. The computed earing profiles and thickness strain distributions were compared with measurements. Comparisons showed that it effects the maximum cup height and thickness strain distribution along the rolling direction.

Keywords

• Cup drawing
• Finite element simulation
• Earing profile
• Thickness strain

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