Document Type : Research Paper



Slab method of analysis has been used for solving metal forming problems for a long time. However it has been restricted to plane strain and axisymmetric problems due to limitations in its formulations. In this paper a new formulation has been proposed so that it could be applied to three dimensional problems in metal forming. A parametric slab has been considered in this analysis and the force balance on the slab was carried to obtain equilibrium equations in terms of these parameters. The parameters in fact are related to the geometry of the final extruded shape, the die and the material flow regime assumed in the formulation. In this way most of the limitations encountered in previous formulations were surpassed. The effect of reduction of area, frictional conditions and other process parameters on the extrusion pressure was investigated. The theoretical results obtained in this paper were compared with the results of finite element method and a good agreement was observed between them.