Numerical design of the die land for shape extrusion

In the extrusion of shapes with a flat-faced die, the proper design of the die land is of critical importance in avoiding the generations of geometrical defects. A methodology for the design of the die land, which consists of a simulation-adjustment iteration, is proposed in this paper. The metal flow in extrusion is simulated by the three-dimensional finite element method and the die land is adjusted according to the simulation result. A criterion for the judgment of the proper die land is suggested by the author. The extrusion of an L-section shape is chosen as the computational example and the result is compared with industrial design.