Numerical investigation for the flexible stretch-stamp forming process of sheet metal

Flexible stretch-stamp forming is a sheet metal forming method derived from flexible stretch forming and multi-point forming, aimed at solving wrinkling defects of large skin parts especially with complex curvatures, prone to occur in the later type of forming processes. To help understand the forming principle and forming characteristics of flexible stretch stamp forming, a large sheet metal part with wavelike surface was selected as the study object and extensive numerical simulations have been conducted using a general commercial finite element software. The main processing parameters of pre-stretching force and wrapping force, respectively, exerted by horizontal and sloping cylinders on forming quality were investigated in detail. Finally, experiments were conducted to estimate the forming performances of flexible stretch-stamp forming.