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In order for the electroplastic effect to take place, the applied electricity must be able to flow from the dies and through the workpiece. Because of this, the interfaces between the dies/workpiece are critical.

This chapter describes the fundamentals behind electroplasticity in metals. Specifically, it focuses on electrical current flow, previous electroplastic theories, and an overall explanation of the electroplastic effect on metals. This overall theory will be supported with experimental results, and electroplastic conclusions will be drawn at the end of the chapter.

Within this book, a modeling strategy for the EAF technique is explained for both compression and tension. Both strategies separate the thermal softening effects from the direct electrical effects and thus produce temperature and force profiles for their respective processes. However, in the real world, manufacturing processes are rarely exclusively compression or tension. Therefore, within this chapter, manufacturing processes that can be applicable to EAF will be explained. These include bending, stretch forming, machining, friction stir welding, and miscellaneous other EAF-industrialization research by researchers other than the authors. In addition, this chapter will include experimental EAF findings for compression, tension, channel formation, springback, and various types of forming.

Electrically assisted forming (EAF) is a recently introduced metal-forming technique capable of enhancing a metal’s formability during deformation and reducing springback after deformation.

For successful implementation of EAF in manufacturing industries, one area that needs to be addressed is the predictability or material response at a bulk level. This chapter introduces the modeling strategy for the electroplastic effect at the macroscale, which are used for compressive modeling (Chap. 5) and tensile modeling (Chap. 6). For macro-level modeling of EAF in Chaps. 5 and 6, the models use a coupled thermo-mechanical approach based on energy and displacement continuity. Additional laws utilized in Chaps. 5 and 6 include: the first law of thermodynamics, Joule’s first law for heat generation, Fourier’s law for conduction, and Newton’s law of cooling.

In this chapter, several control approaches are described for forming a metal under an electrical current field. In addition, the approaches are demonstrated and potential applications for these control schemes are discussed. The specific examples where closed-loop control is used to determine the process output are for constant force forming, constant stress forming, and constant current density (CCD) forming. Last, the feasibility toward model-based control (MBC) is discussed for the models developed in Chaps. 4– 6.

The overall goal of this chapter is to develop a model for an electrically assisted forging process and then use this model to highlight specific sensitivities and relationships within the EAF process. A modeling strategy will be defined, based on existing conventional forging equations. These equations will then be modified to account for the electroplastic effect in an EAF process.

In previous chapters, we have explored the underlying physics behind electrically assisted manufacturing (EAM), how to model the phenomenon, and its effect on deformation process forces, power, and resultant microstructure. In this chapter, we aim to explore the feasibility of implementing EAM on a commercial scale, primarily specific design requirements, cost, and sustainability impact on the manufacturing system as a whole.

This chapter contains modeling work for sheet metal subject to an applied direct electrical current in uniaxial tension. The modeling is divided into a thermal and mechanical approach which is combined to a thermo-mechanical model to predict the deformation behavior during EAF.

Deformation of metals is one of the key manufacturing processes for adding value in secondary operations. Deformation as a process evolved soon after metal refinement in ancient times to shape tools and other functional parts. With the dawn of the second Industrial Age, the availability of localized power sources allowed for the development of more standardized automated processes for metal deformation, such as forging, stamping, drawing, and extrusion. These processes gave rise to high-value, standardized components for construction, vehicles, and consumer goods.