Investigation of Parameters Influencing Forming Force and Thickness Distribution in Single Point Incremental Forming of AA3105-St12 Two-Layer Sheet

Single point incremental sheet forming is a die-less forming technology in which the sheet metal is formed progressively by the movement of a tool in the specified path. In this paper, the single point incremental forming of the AA3105-St12 two-layer sheet is studied through numerical and experimental approaches. Numerical simulation of the process is done based on the finite element method. The validity of the numerical model is evaluated via a comparison between the obtained numerical and experimental results. The force applied to the forming tool, the thickness distribution of formed sheets, and the maximum thinning that occurred in aluminum and steel layers were studied. The effects of the parameters of the two-layer sheet including total thickness, thickness ratio of layers, and arrangement of layers were investigated as well. The results showed that regardless of the contact of the steel or aluminum layer with the tool, increasing the ratio of the thickness of the steel layer to the thickness of the aluminum layer reduces the thinning in the aluminum layer and increases it in the steel layer. Hence, thinning becomes more severe in each layer when it is in contact with the forming tool.