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Previous studies have shown that the presence of a pulsed electrical current, applied during the deformation process of an aluminum specimen, can significantly improve the formability of the aluminum without heating the metal above its maximum operating temperature range. The research herein extends these findings by examining the effect of electrical pulsing on 5052 and 5083 aluminum alloys. Two different parameter sets were used while pulsing three different heat-treatments (as-is, 398°C, and 510°C) for each of the two aluminum alloys. For this research, the electrical pulsing is applied to the aluminum while the specimens are deformed without halting the deformation process (a manufacturing technique known as electrically assisted manufacturing). The analysis focuses on establishing the effect of the electrical pulsing has on the aluminum alloy’s various heat-treatments by examining the displacement of the material throughout the testing region of dogbone-shaped specimens. The results from this research show that pulsing significantly increases the maximum achievable elongation of the aluminum (when compared with baseline tests conducted without electrical pulsing). Another beneficial effect produced by electrical pulsing is that the engineering flow stress within the material is considerably reduced. The electrical pulses also cause the aluminum to deform nonuniformly, such that the material exhibits a diffuse neck where the minimum deformation occurs near the ends of the specimen (near the clamps) and the maximum deformation occurs near the center of the specimen (where fracture ultimately occurs). This diffuse necking effect is similar to what can be experienced during superplastic deformation. However, when comparing the presence of a diffuse neck in this research, electrical pulsing does not create as significant of a diffuse neck as superplastic deformation. Electrical pulsing has the potential to be more efficient than the traditional methods of incremental forming since the deformation process is never interrupted. Overall, with the greater elongation and lower stress, the aluminum can be deformed quicker, easier, and to a greater extent than is currently possible.

Recent development of electrically assisted manufacturing processes proved the advantages of using the electric current, mainly related with the decrease in the mechanical forming load, and improvement in the formability when electrically assisted forming of metals. The reduction of forming load was formulated previously assuming that a part of the electrical energy input is dissipated into heat, thus producing thermal softening of the material, while the remaining component directly aids the plastic deformation. The fraction of electrical energy applied, which assists the deformation process compared to the total amount of electrical energy, is given by the electroplastic effect coefficient.The objective of the current research is to investigate the complex effect of the electricity applied during deformation, and to establish a methodology for quantifying the electroplastic effect coefficient. Temperature behavior is observed for varying levels of deformation and previous cold work. Results are used to refine the understanding of the electroplastic effect coefficient, and a new relationship, in the form of a power law, is derived. This model is validated under independent experiments in Grade 2 (commercially pure) and Grade 5 (Ti-6Al-4V) titanium.

Recent development of electrically-assisted manufacturing (EAM) processes proved the advantages of using the electric current, mainly related with the decrease in the mechanical forming load and improvement in the formability. Erom EAM e.xperiments, it has been determined that a portion of the applied electrical power contributes toward these forming benefits and the rest is dissipated into heat, defined as the electroplastic effect. The objective of this work is to experimentally investigate several factors that affect the electroplastic effect and the efficiency of the applied electricity. Specifically, the effects of various levels of cold work and contact force are explored on both Grade 2 and Grade 5 Titanium alloys. Thermal and mechanical data prove that these factors notably affect the efficiency of the applied electricity during an electrically-assisted forming (EAF) process.

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