Numerical and experimental investigation of hole flangeability of AA6061 alloy

Abstract Hole flangeability is a measure of edge formability or local formability, and it is important for forming processes like stretch flanging. Hole flangeability of sheet metals is evaluated by determination of hole expansion ratio (HER) using a standard hole expansion test (HET). In the present work, numerical and experimental investigation of hole flangeability has been carried out on 1.6mm thick AA6061 alloy sheets. The material model plays an important role in the accuracy of predicted results in numerical simulations. The simulations have been carried out using two different work hardening laws (Swift and Voce). The failure has been predicted using the experimentally determined forming limit curve (FLC) of AA6061 alloy sheets. HER and thickness have been predicted along the edge of the expanded hole by simulation. The predicted HER and thinning from FE simulation have been validated experimentally by performing hole expansion tests according to ISO 16630-2009 using a conical punch. The predicted results have been found to be in good agreement with the experimental results.