Experimental Investigation of Electroplastic Effect on Ductile Fracture Phenomenon of Annealed AA6061 Aluminum Alloy in Different Stress States through Hydraulic Bulge Test

High-temperature forming is a conventional method for improving the formability of metals, but it involves high costs and long processing times. As an alternative, this study investigates the electroplastic effect (EPE) on the formability of annealed AA6061 aluminum alloy under different stress states. Hydraulic bulge tests were performed on circular and oval notch specimens, both with the application of electric current at appropriate current parameters and without the application of electric current. The results show that applying electric current at appropriate current parameters increased the equivalent plastic strain at fracture by 3.92% and 5.55% in circular and oval notch specimens, respectively. Dome height increased, fracture pressure decreased, and dome thickness was reduced, all indicating enhanced formability. The effectiveness of the EPE was found to decrease with increasing stress triaxiality. These findings confirm that electric current-assisted forming can improve ductile fracture behavior in AA6061 under complex loading conditions, offering potential for industrial applications.