Numerical Simulation of Axisymmetric and Asymmetric Extrusion Process Using Finite Element Method

Abstract

The deformation load is the most important parameter in the press design. The flow of metal, consequently load, is largely influenced by the geometry of the die and hence the geometric shape of the tools is the main factor by which an optimum load can be developed. In extrusion process the strain distribution, resulting from deformation load, and other important variables that influence material structure, such as a hydrostatic stress, are strongly dependent on the geometry of the die. In the present investigation using linearly converging die profiles, the extrusion of simple and advanced polygons such as circular, square, triangular, hexagonal, heptagonal, octagonal, L-, T-, and H- sections from round billet have been numerically simulated. Mathematical equations describing the die profiles were evaluated. A solid CAD model for the linearly converging die profile was made using Autodesk Inventor 2013 software and numerical analysis using DEFORM 3D software for extrusion of the above sections from round billet was then performed to determined, for dry and lubricated condition, the load prediction, effective stress, effective strain, strain rate, velocity and temperature distribution during the deformation. It is found that the predictive loads for advance (asymmetric) shapes are found to be higher than that of the simple shapes. While there is no marked difference between the predictive load for simple (axisymmetric) shapes, the L-section has the highest extrusion load, followed by T-section and the H-section given the least pressure.