Optimization of Die Geometry Using Thermal FEM Analysis in Die Casting Process

In high pressure die casting, due to thickness differences and non uniform temperatures of the workpiece when it is removed from the die, geometrical deformations arises. The related mechanism may be individuated in the different thermal shrinking that causes plastic deformation, complex springback and residual stresses. This phenomenon is worsened by the high productivity required to this process that imposes a very reduced cycle time. The usual die design practice considers only the linear shrinking of the product during the cooling while geometrical deformation are not taken into account. The aim of this paper is the presentation of a die design strategy based on thermo-elasto-plastic FEM simulation that can allow the designer to improve the die design in order to compensate the geometrical errors.