Aluminum is expected to gain popularity as material for the bodies of the next generation of lighter and more fuel-efficient vehicles. However, its lower formability compared with that of steel tends to create considerable problems. A controllable restraining force caused by adjusting the penetration of drawbeads can improve the formability. This paper describes the effects of temporal variations in drawbead penetration on the strain distribution in a symmetric stamped part. Comparison of the results of numerical simulations with the corresponding experimental results shows that the predictions of strain distribution on the panel are in very good agreement. Furthermore, forming limit diagram analysis indicates that the active drawbead concept is beneficial to the formability of AA 6111-T4.

Issue Section:
Technical Papers
Keywords:
aluminium alloys, silicon alloys, magnesium alloys, copper alloys, numerical analysis, forming processes, ductility, drawing (mechanical), Aluminum Sheet, Drawbeads, Formability
Topics:
Aluminum, Forming limit diagrams, Fracture (Materials), Fracture (Process), Metal stamping, Sheet metal, Simulation, Trajectories (Physics), Flanges, Finite element model, Failure, Blanks, Aluminum alloys, Computer simulation, Vehicles
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Copyright © 2001
 by ASME
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