Analysis of Hydrostatic Extrusion by the Finite Element Method

Abstract
An elastoplastic analysis of hydrostatic extrusion is made using the finite element method. The effect of frictional coefficient on the spread of plastic zone, the pressure-displacement curve, and the stress and the strain distributions are studied for the non-steady state in plane-strain and axisymmetric extrusions. Comparisons of results between the finite element solution and slip-line solution and between plane-strain and axisymmetric extrusions are presented. Tensile stresses on the surface of the extruded part behind the die are found to exist. It is also found that the die pressure is high near the die entry and exit and that the surface of the billet in front of the die entry tends to contract.