Incrementally formed stiffeners effect on the reduction of springback in 2024-T3 aluminum after single point incremental forming

Single Point Incremental Forming (SPIF) is a relatively new process to form sheet metal. SPIF utilizes machines such as CNC's and mills to form a part by making several spiraled passes, deforming the metal a certain distance, known as the step-size, with each pass. One major issue with this process is global springback. Once the metal is removed from its clamping fixture, the residual stresses that resulted from the forming process cause the material to springback. The purpose of this paper is to demonstrate how incrementally forming a stiffener on the outside of the desired geometry will manipulate the stress concentrations in the metal, and effectively reduce the amount of global springback that occurs after the specimen is unclamped from its fixture. For these tests, stiffeners were formed on the outside of a truncated pyramid; the material used for these test was 2024-T3 aluminum. After the work pieces were removed from their clamping fixtures, the amount of springback that they experienced was examined using Geomagic software to determine the ideal stiffener parameters for reducing global springback for a truncated pyramid in 2024-T3 aluminum.