The study is concerned with the analysis of axisymmetric forward extrusion by the finite element method. The distribution of stresses and strains as well as the deformation pattern in sold extrusion is very important for the improvement of product quality.
The rigid-plastic finite element formulation is one of the most efficient numerical methods to obtain such detailed informations. The initial velocity field is determined by assuming the material as a Newtonian fluid through an arbitrary-shaped axisymmetric die. The Workhardening effect and the friction of the die-material interface are considered in the formulation. Some reduction of area and die shapes (conical and biquadratic) are chosen for computation.
Experiments are carried out for aluminum and steel specimens using conical and curved dies. It is found that the experimental observation is good agreement with FEM results. Furthermore, the strain distribution in curved (biquadratic) dies is shown to be more uniform than in conical dies at the same reduction area.
