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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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Automotive manufacturers are continuously striving to meet economic demands by designing and manufacturing more efficient and better peiforming vehicles. To aid this effort, many manufacturers are using different design strategies such to reduce the overall size/weight of certain automotive components without compromising strength or durability. Stainless steel is a popular material for .such u.ses (i.e., bumpers and fuel tanks), since it possesses both high strength and ductility, and it is relatively light for its strength. However, with current forming processes (e.g., hot working, incremental forming, and superplastic forming), extremely complex components cannot always be easily produced, thus, limiting the potential weighl-.iaving and performance benefits that could be achieved otherwise. Electrically-assisted manufacturing (EAM) is an emerging manufacturing technique that has been proven capable of significantly increasing the formability of many automotive alloys, hence the "electroplastic effect". In this technique, electricity can be applied in many ways (e.g., pulsed, cycled, or continuous) to metals undergoing different types of deformation (e.g., compression, tension, and bending). When applied, the electricity lowers the required deformation forces, increases part displacement or elongation and can reduce or eliminate springback in formed parts. Within this study, the effects of EAM on the bending of 304 Stainless Steel sheet metal will be characterized and modeled for different die widths and electrical flux densities. In previous works, EAM has proven to be highly successful on this particular material. Comparison of three-point bending force profiles for nonelectrical baseline tests and various EAM tests will help to illustrate electricity's effectiveness. An electroplastic bending coefficient will be introduced and used for modeling an electrically-assisted (EA) bending process. Additionally, the springback reductions attained from EAM will be quantified and compared. From this work, a better overall understanding of the effects and benefits of EAM on bending processes will be explained.

In recent years, the industrial demand for strong, lightweight metal alloys, such as 5052 Aluminum, has increased. Previous research has shown that the Electrically-Assisted Manufacturing (EAM) technique, where electricity is applied to a material during deformation, improves the material behavior of most metals. By applying electricity continuously or by applying electrical pulses during deformation, the technique reduces the material’s flow stress and increases its achievable elongation. Considering this, the research presented herein investigates applying pulsed EAM when fabricating channels from Al 5052. To fully determine the technique’s influence on the manufacturing process, the effects of current density, pulse duration, pulse period, and die speed are examined. The results demonstrate that the channel formation process is improved using EAM. The improvements include reduced force/energy requirements and increased achievable channel depth.