The Control of Shape Fixation and Springback of Aluminum Alloy Sheet in Model Forming

The shape and dimensional failures were investigated by the hat-shape bend forming and the model forming of a door outer panel. In the hat-shape bend forming the springback and the side wall curl after forming depend on the strength of sheet material, the shape and dimension of tools, lubricants and the blank holding force. In the forming of door outer model panel the surface deflection around a handle portion appeared distinguishably. In order to suppress the surface deflection such a countermeasure as bottoming is required. It is difficult to change the material properties in a wide range in the manufacturing processes of aluminum alloy sheets. Therefore the development of forming techniques suitable for aluminum alloy sheets is desired.