Analysis of incremental sheet metal forming using the upper-bound approach

Abstract

The incremental sheet metal forming is a flexible process producing various parts with no need for dedicated dies. In this article, the upper-bound approach is used to study the deformation zone of single point incremental forming of truncated cones. The velocity field and the dissipated power of the process are achieved using an assumed deformation zone and streamlines defined by Bezier curves. The tangential force acting on the tool is attained by optimizing the presented upper-bound solution. Then, influences of the effective parameters including vertical pitch, initial thickness, tool diameter, and wall angle on the tangential force and the predicted equivalent strain are investigated. A strain hardening law is utilized to consider the work hardening behavior of sheet metals. In order to validate the presented upper-bound solution, predicted tangential forces are compared with experimental data reported in literature for forming AA3003 truncated cones. The comparison shows an appropriate agreement between experimental and predicted tangential forces.