Electro assisted treatments as new sustainable frontiers of sheet metal forming

Sheet metal forming processes are widely used in various application fields such as automotive, aerospace, electronics. The market of these parts is gaining great interest, and an important role is played by the thin-walled parts obtained by forming rolled sheets. For instance, aircraft fuselage panels or car parts (e.g. hoods, doors or floors) are typically produced by forming rolled sheets. Nervertheless, conventional sheet metal forming processes are very energy intensive. In the current scenario, the need for more sustainable manufacturing processes is becoming even more imperative. Thus, conventional manufacturing processes need to be stronger day by day, so also these be re-designed or even re-thought to reduce their environmental footprint.

Recently, the effect of the electric current on the plastic deformation behavior of metals is gaining increasing interest. In particular, some researchers carried out matching temperature tests to decouple the thermal effect, they observed that in some conditions the electric current leads to a reduction of the yield strength beyond the one achieved when heating up the material at the same temperature achieved during the electro assisted tests.

To the current state of the art, it is quite clear that for some materials, and under certain conditions, a full understanding of the process is yet to be achieved, the flow of the electric current during the plastic deformation enhances the formability and reduces the loads required. It is still under debate the mechanism underlying this effect, several different theories are on the table:

In this presentation, the investigation of the effect of the electric current on various metal alloys sheets is presented and discussed. The advantages in terms of both mechanical properties and sustainability of these innovative treatments and the frontiers in this regard are deeply discussed.