Plastic Deformation of Copper and Steel in Hot Extrusion Through Conical Dies

Abstract

A method of observing flow lines during metal forming was applied to the conical die extrusions of oxygen-free high-conductivity copper at 800 deg F and of SAE 1018 steel at 1800 deg F, under various extrusion conditions. The experiments were carried out at the Metals Processing Laboratory, Wright-Patterson Air Force Base. The deformation characteristics based on experimentally obtained flow lines were examined in terms of the velocity components and the effective strain distribution, and the effects of materials, ram speed, die cone angles, and reductions on the deformation characteristics were discussed. For calculating velocity components and effective strains, the computer programs developed at the University of California, Berkeley, were used with slight modifications.