Three Dimensional Upper Bound Modelling for Extrusion of Round-to-Octagon Section Using Linearly Converging Die
The extrusion of section from round billet poses a great challenge for theoretical modeling of the process using upper bound method. The greatest difficulty in three-dimensional upper bound method is to determine kinematically admissible velocity field. The SERR (Spatial Elementary Rigid Region) technique is fairly applicable for analyzing extrusion of sections having re-entrant corners. A modified version of SERR technique has been used for extrusion of octagon sections from round billet through a linearly converging die. The circular cross section of the round billet is approximated by a regular polygon of equal area. The extrusion pressure has been computed for different boundary condition at the die billet interface. The optimum die geometry has been determined.
A. Erman Tekkaya and Nooman Ben Khalifa
K. P. Maity and A. K. Rout, "Three Dimensional Upper Bound Modelling for Extrusion of Round-to-Octagon Section Using Linearly Converging Die", Key Engineering Materials, Vol. 424, pp. 189-196, 2010