FEM Simulation of the Whole Circle of Aluminum Hot Extrusion Using Circular Dies With Different Extrusion Angle

Abstract

On of the most typical forming processes used for the production of long, straight semi-finished products in the form of various section geometries is extrusion. Hot extrusion is a thermo-mechanical process whish involves complicated interactions between process parameters, tooling and deforming material /1,2/. In the present paper, FEM simulation is performed in the aluminum extrusion using circular dies with different geometries in order to extract quantitative simulating results regarding various forming parameters. Most specifically the parameters that are investigated are the die design-geometry, the process parameters (i.e. ram speed, container temperature, billet temperature) and the product quality (i.e. extruded shape, surface condition). The finite element modeling is based on 3D simulation tools using the DEFORM 3D software /3–5/. The used work piece is the aluminum AA6061 in cylindrical form with a diameter of 14 mm. The used material for the extrusion die is the hot work steel AISI H13. The geometry of the die is circular with a variation in die angle. The container and the billet temperature will vary from 450 to 550 degrees, and the mandrel (ram) speed will be at the range of 2 mm/sec. On the basis of simulating results such as pressure distribution on the extrusion die, effective stresses on the billet and product quality, new and improve die geometry will be introduced. Although the simulation problem is an axisymmetric one the authors decide to proceed with 3D FEM simulation in order to examine and verify the 3D simulating results. This paper is the first part of a further research project in which more complicated die geometries will be used as simulating and experimental specimens. In addition to simulating results, experimental results will be presented in the next few months.