A drawbead model with sheet metal passing through multiple bending-unbending processes was employed in this study to understand the springback phenomenon and to develop a numerical simulation technique for more accurate prediction of the springback process. The deformation process is simulated using an implicit finite element modeling code. The predicted results were compared with the physically measured ones, including clamping and restraining forces, thickness strains, and the curvatures of the deformed sheets. Consideration of the Bauschinger effect and employment of a combined isotropic and kinematic hardening models greatly improve the prediction accuracy. Stress and strain histories under various conditions during the drawing process are studied in detail in an attempt to provide a better basis for comparison for dynamic explicit solutions.

Issue Section:
Technical Papers
Keywords:
Bauschinger effect, metals, bending, stress analysis, stress-strain relations, forming processes, simulation, drawing (mechanical), modelling, work hardening, finite element analysis
Topics:
Hardening, Kinematics, Stress, Shells, Simulation
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Copyright © 2001
 by ASME
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