The Effect of Electroplasticity on the Flow Behavior of AA7075 in T6 Temper

Warming forming, or the combination of cold forming, and multiple heat treatment processes are usually used to obtain AA7075 parts in T6 temper. However, the above-mentioned methods increase the forming cycle and cost, and lead easily to change in the microstructure. In this paper, a new forming process is proposed, namely pure electroplastic-assisted thermal forming (PEPATF) process, which can reduce the forming temperature by using pure electroplastic/non-thermal effect to compensate plasticity loss caused by the decrease of temperature. In order to research the mechanism of electroplastic effect, oven-heating uniaxial tension at different temperatures and electrically assisted uniaxial tension test at different temperatures and current densities are performed for AA7075-T6. On the one hand, the results show that at the same temperature, the flow stress obtained by electrically assisted heating is lower than that obtained by oven-heating, indicating that pure electroplasticity exists and is more obvious with the increase of temperature. Moreover, at the same temperature, the flow stress decreases with the increase of current density at the same temperature. On the other hand, the elongation obtained by electrically assisted uniaxial tension is higher than that obtained by oven-heating uniaxial tension. For electrically assisted uniaxial tension, the largest elongation is at 150 °C.