Abstract: The age forming technique, characterized by huge springback, has been developed to manufacture integral wing-skin panel components. The die surface should be modified, based on accurate prediction of springback, to eliminate the effect of springback on forming precision. A finite element method (FEM) drove iterative die surface modification algorithm is presented for age forming of aluminum alloy plate. This algorithm is used in die surface modification for the arc, sphere and saddle parts. The maximal shape errors of the arc-part and sphere-part are reduced below 0.4 mm, after four iterations. And after five iterations, the maximal shape error of the saddle-part is reduced below 0.5 mm, except for the four corners of it. This algorithm’s advantages of high precision and fast convergence rate are confirmed.

Key words: aluminum alloy, age forming, FEM, springback, die design