The role of the friction during the equal channel angular pressing of an IF-steel billet

It is well known that high levels of friction induce adherence effects in materials processed by equal channel angular pressing (ECAP) promoting some degree of heterogeneity along the deformation zone. In the present paper, the role of the friction in relation of die geometry considering frictionless, ideal lubrication and severe friction conditions of an interstitial free (IF) steel deformed by ECAP technique using plane strain finite element models was investigated in details. The analysis of adherence at the billet–die contact region during only one pass of deformation was carried out in a quasi-static form at room temperature. Independent of the die channels intersection angle (90° or 120°) analyzed an adherence phenomenon was observed under determined friction conditions. It can be concluded that it is necessary to establish an upper limit to the friction coefficient in order to avoid the adherence effect in two-dimensional finite element simulations.