Analytical, Numerical, and Experimental investigation of wrinkling for deep drawing laminated sheet (Al۲۰۲۴/Polyamid۶/ Al۲۰۲۴)

Laminated aluminum sheets sandwiched with a polymer core (Al۲۰۲۴/Polyamid۶/ Al۲۰۲۴) are increasingly used for automotive applications to boost vehicle’s vibrationdamping performance without adding additional weight. Wrinkling phenomenon has been one of the major limiting failure modes in sheet metal forming which can be eliminated with an increase in the blank holder force (BHF). Because of the significant difference in material properties between the polymer core and the aluminum skin, it has been always great challenge to predict their wrinkling onset and wrinkling pattern in deep drawing process. This contribution presents an efficient analytical model as well as a FE computation of the blank holder force, which leads to control local stability failure (wrinkling) and achieve optimum BHF in sandwich sheets forming. In the analytical model,energy method is used to predict the wrinkling. The results of the FE calculations and the analytical model are in good agreement with experimental data.

Keywords:

sandwich sheet , Wrinkling criteria , Finite element analysis , Plastic wrinkling , BHF