The area under the stress-strain curve for any material is the work/unit volume required to 'move' it. Perhaps you could start with that and figure how much volume you are moving. Otherwise, become friends with someone experienced with forming and ask them for their estimate.
not really a SWX sim sort of problem. The deformations will be large and the element distortions will be severe. Might be better done with an Eulerian formulation or possibly with Lagragian formulation with in solution re-meshing. Once you get over ~10% strain in SWX sim all bets are off.