Constitutive Modelling of AZ31B-O Magnesium Alloy for Cryogenic Machining

The success of a FE model for metal cutting process is strongly dependent on the accurate characterization of the workpiece material, under similar conditions as those found in metal cutting. In this paper, dynamic shear tests using a Gleeble machine have been performed on 4 mm thickness disks of AZ31B-O magnesium alloy, using a special designed tool. In order to include the effects of the cryogenic cooling in the material behavior, the specimens have been submitted to temperatures ranging from -25 °C to 400 °C. A Johnson-Cook constitutive model has then been identified in order to describe the flow stress in machining.