An experimental investigation of the influence of the Bauschinger effect on springback predictions

An efficient and low cost multiple bending experiment has been designed to investigate the influence of the Bauschinger effect on springback in sheet metal forming. Most sheet metal elements undergo complicated deformations during forming process. In general, the influence of the Bauschinger effect must be considered for obtaining accurate springback predictions. In the work reported here, three different AISI steel sheet metals (high strength, bake hard, and AKDQ), and one type of aluminum sheet metal (AA6111-T4) were used as experimental materials. These materials are used widely in the automobile industry for car panels. From these experiments, it can be concluded that the influence of the Bauschinger effect on springback is more significant for aluminum AA6111-T4 than for steels. Both the deformation history and the Bauschinger effect must be considered to predict springback in AA6111-T4 stamping parts.