Mathematical modeling of V-die bending process

V-die bending is a non-steady state forming process, in which bending moment varies during forming; stress--strain distribution differs in different cross-sections of a bend. By assuming that an isotropic-hardening von Mises material undergoes plane bending, the moment of internal stresses is expressed as a function of the curvature of the bend, sheet thickness and properties of the material. With the constitutive equations given, one can calculate the configuration of a sheet metal in bending and predict its elastic springback on removing load. The theoretical results have been compared to the experimental data, and good agreement has been found. Materials were: DRQ 1147, DOCOL 220, DOCOL 260, and SIS 2322. Graphs. 10 ref.--AA