A Study of Preform Design on Backward Extrusion for Improved Hardness Distribution
In this paper, the finite element method is used to investigate the effect of preform shapes on the strain hardening distribution in the wall of the extruded cup of backward extrusion. A series of simulations on the backward extrusion with three different preform shapes (flat, concave and convex) and without preform using the FEM program DEFORM 2D was carried out, respectively. The influence of preform shapes on the effective strain distribution in the extruded wall was examined. A hardness vs. effective strain curve for an annealed AL6061 Aluminum was first obtained using a simple forging test in conjunction with FE simulations, then the curve was used to convert the effective strain distribution into the hardness distribution in the extruded wall. The results of FEM calculations reveal that the concave shape preform has the best effect on the hardness strengthening at the extruded wall of backward extrusion.
Faruk Yigit and Mohammed S. J. Hashmi
C. T. Kwan and Z. K. Chang, "A Study of Preform Design on Backward Extrusion for Improved Hardness Distribution", Advanced Materials Research, Vol. 445, pp. 247-252, 2012