An approximate solution for axisymmetric extrusion of porous material

Abstract

The paper concerns with a theoretical solution for axisymmetric extrusion of porous material through a conical die. It is assumed that the material is rigid plastic, obeying Green’s yield criterion and its associated flow rule. Coulomb’s friction law is adopted at the die surface. Hill’s method is used to derive simplified equilibrium equations. Therefore, the solution reduces to ordinary differential equations which are solved numerically. The variation of product porosity with process parameters as well as the distribution of the porosity in the plastic zone is illustrated. The solution is compared to another approximate solution based on a singular yield criterion.