MODELING THE PROCESS OF BACK EXTRUSION OF POROUS BLANKS

Abstract

The process of back extrusion of sintered powder blanks was studied by computer simulation method. The influence of the presence of imperfect contacts between powder particles is considered. At the initial stage, the blank is sedimented and compacted, and then the extrusion process begins to prevail. The distribution of residual porosity and accumulated plastic deformation of the material throughout the part volume is uneven. The zone of difficult deformation is located directly under the deforming punch. The minimum density and accumulated deformation correspond to the field of the surface free of load. The presence of imperfect contacts leads to the appearance of zones of softening of the powder material and a decrease in the amount of accumulated plastic deformation in these zones.