Abstract: Based on the model of bending and reverse bending for bland sheet bending with multi-angular deformation, the basic sheet deformations including bending, deep drawing, bulging and flanging are studied, The phenomena of bending and reverse bending in these deformations are analyzed. The decision condition is given as the reverse bending deformation occurs, Also, the conception of corresponding bending angle is presented and the proper methods to calculate the deformed force and energy are given. It is pointed out that the reverse bending deformations are not occur in initial stages of many forming processes.

Key words: Bending and reverse bending, Bulging and flanging, Deep drawing, Sheet metal forming