Numerical Modelling and Simulation of Vortex Extrusion as a Severe Plastic Deformation Technique Using Response Surface Methodology and Finite Element Analysis

Abstract

Vortex extrusion (VE) as a severe plastic deformation method that imposes high values of strain with simultaneous torsion and extrusion of a workpiece was studied in this paper. Response surface methodology was used for investigation the relationship between reduction in area (RA), twist angle (φ), length of twist zone (L) and position of control points in Beziers’ formulation (C1) as input parameters, and efficient twisting of the material and punch load (steady state load) as output parameters using streamline proposed 6-indent VE die in different frictional conditions. Accuracy of the finite element analysis (FEA) results was evaluated with experimental data before of using FEA to obtain the responses. Analysis of variance was used to evaluate the effect of the parameters and their interaction on the responses and to develop a mathematical model for the responses. Results showed that, beside the effects of φ, RA, L on twisting of the materials in both frictionless and frictional conditions, interaction of φ and RA (φ × RA) is a significant parameter in the frictional condition. However, φ, RA and interaction of RA with RA (RA × RA) were considered as the significant parameters that affect the load of the process in both frictional conditions. Finally the proposed mathematical model for load of the process was evaluated with experimental data in similar conditions. It was concluded that the results of the modeling and experimental data are in a good agreement.