The reduction of deformation energy and increase in workability of metals through an applied electric current

Many manufacturing processes (e.g., forging, rolling, extrusion, and sheet metal) rely on the application of heat to reduce the forces associated with fabricating parts. However, due to the negative implications associated with hot working, another more efficient means of applying energy is desired. This paper investigates the changes in the material properties of various metals (aluminum, copper, iron, and titanium based alloys) in response to electricity flow. Theory involving electromigration, and, more specifically, electroplasticity, is examined and the implications thereof are analyzed. It is shown that, using electrical current, the flow stresses in a material are reduced, resulting in a lower specific energy for open-die forging. It is also shown that an applied electrical current can increase the forgeability of materials, allowing greater deformation prior to cracking. Additionally, elastic recovery is shown to decrease when using electricity during deformation. Finally, For most materials, these effects were dependent on strain rate.