A constitutive law for the thermo-mechanical modelling of magnesium alloy extrusion

Abstract

Metal extrusion as one of the production processes for semi-finished products plays an important role for the optimisation of wrought magnesium alloys. A mechanistic approach for the modelling of the coupled deformation and temperature fields is presented here. It accounts for the strain rate and temperature dependence of the mechanical properties as well as for the evolution of anisotropy and tension-compression asymmetry of magnesium alloys. In an attempt to calibrate the model parameter, tension and compression tests at different temperatures and strain rates are conducted for two different alloys, namely ZE10 and ZEK100. Extrusion trials are simulated and the predicted results are compared in terms of punch force and temperature history. Conclusions are formulated with respect to the significance of model parameters.