Experimental and Numerical Determination of Limiting Drawing Ratio of Al3105-Polypropylene-Al3105 Sandwich Sheets

Sandwich structures are gaining wide applications in aeronautical, marine, automotive, and civil engineering. Since such sheets can be subjected to stamping processes, it is crucial to characterize their forming behavior before trying out any conventional forming process. To achieve this goal, sandwich sheets of Al 3105/polymer/Al 3105 were prepared using thin film hot melt adheres. Different sandwich specimens with different thickness ratios (of polymer core to aluminum face sheet) were prepared. Throughout an experimental effort, the limiting drawing ratios (LDRs) of the sandwich sheets were determined. Besides, the LDR of the sandwich sheets were predicted using finite element analysis simulations by considering Gurson-Tvergaard-Needleman damage model. The results show the capability of the damage model to predict the LDR and the location of damaged zone in a workpiece during a forming operation.