The process of backward extrusion of polygonal shaped billets to internally circular hollow sections was simulated using finite element method. The software used in this investigation was ABAQUS (explicit) program. The objective was to study the effect of different parameters involved in the backward extrusion such as material flow, friction, reduction of area and shape complexity on the process itself. Using the finite element simulation, grid pattern deformations were obtained which would be very useful for the die and process design. The simulation was carried out for the backward extrusion of square, rectangular, hexagonal and octagonal billets into internally hollow circular sections. The results obtained from these simulations were plotted in terms of the extrusion load and pressure versus reduction of area, shape complexity factor and friction factor. Also contours for strain and stress were obtained from the finite element analysis. It was shown that as the percentage reduction of area increases the extrusion pressure and force increase with it. The effective strain near the parts of the billet which were in contact with the punch was shown to be at their maximum. Maximum deformation was observed to occur in the internal walls of the final extruded product. The results obtained in this work were compared with similar results from analytical and experimental works of others and good agreements were observed.
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