An Analysis of Deformation Characteristics and Interfacial Friction Conditions in Simple Upsetting of Rings

Abstract

Presented in this paper is an analytical investigation of the deformation characteristics at the outer equator and the change in diameter of the inner equator in simple upsetting of flat rings. Material strain hardening is considered inasmuch as the ratio of the friction stress at the tool-workpiece contacts and the material effective stress is assumed to remain constant in the process of deformation. The surface stress components are calculated by means of the Levy–Mises equations, in which the development of anisotropy is disregarded. Numerical comparisons are made with published experimental data.