Finite Element Investigation of the Effect of Hardening Behavior of Alloys on Equal Channel Angular Pressing Performance

Abstract

In most of the simulation studies of equal channel angular pressing (ECAP) it has been assumed that materials obey isotropic hardening law. However, in the case of precipitation hardenable alloys, an accurate prediction of the deformation behavior requires incorporation of kinematic hardening model. In this study, the influences of kinematic, isotropic and combined hardening laws on deformation behavior have been investigated. For this purpose, an ECAP die consisting of two 120° channels has been selected, and the effect of hardening law on the strain profile and ram pressure at the final exit channel has been studied. The simulation results showed that the hardening mechanism does not affect the strain profiles extensively; but, when kinematic hardening mechanism was considered the ram pressure decreases significantly due to less hardening of the material during reverse loading in the final exit channel.