Analysis and modelling of a novel process for extruding curved metal alloy profiles

An analytical upper-bound-based model for predicting curvature of bent metal alloy profiles obtained through a novel extrusion process, differential velocity sideways extrusion (DVSE), previously proposed by the authors, has been first-time developed. Finite element modelling and simulation and model material experiments, which were validated by extrusion of AA1050, have been performed to determine the geometry of the deformation zone and assess the accuracy of the analytical model. The extrusion force, curvature, and effective strain predicted by the analytical method agreed well with results from experiments and FE simulation. It was shown that the punch with a lower velocity experiences a lower extrusion force, which increases both with increase of its velocity and the extrusion ratio. The extrusion force on the faster punch with a constant velocity v1 changes quite slightly with the increase of the velocity v2 of the slower punch. Various values of curvature, which decrease with the increase of the punch velocity ratio v2/v1 and the decrease of the extrusion ratio, can be achieved through the DVSE process. DVSE is a novel process which leads to larger effective strain per pass than that in the equal channel angular extrusion (ECAE).