Locally Applied Direct Electric Current’s Effect on Springback of 2024-T3 Aluminum After Single Point Incremental Forming

Incremental forming is a sheet metal forming technology that utilizes a spherical tipped tool and a CNC machine to form a part through a series of spiraling tool paths. Springback is one of the largest concerns for incremental forming since a part can be the exact shape desired after forming until the part is unclamped from its forming fixtures, at which point it will springback due to the residual stresses resident in a part due to the forming process. This paper demonstrates how locally applied electric current can be utilized to reduce the springback due to residual stresses. The tests conducted in this paper demonstrate this concept via incrementally formed truncated-pyramid shapes that were formed from 2024-T3 aluminum. The residual stress concentration locations of the pyramid were determined using FEA. Direct electric current was locally applied to the stress concentrations of the pyramid prior to unclamping. Various current densities, time intervals, and electrical pulse locations were examined to find the ideal conditions for reducing springback for a tested geometry of 2024-T3 aluminum.