Die Casting of Magnesium Alloys - The Importance of Controlling Die Filling and Solidification 2003-01-0183

High pressure die casting is characterised by rapid die filling and subsequent rapid cooling and solidification of the metal in the die. These characteristics are favourable for the mechanical properties of magnesium die casting alloys. Since the filling pattern and the cooling rate of the metal is highly dependent on both process parameters and geometry of the part, there is a natural variation in mechanical properties. Variations in filling pattern can be caused by differences in the filling conditions set up by the gating system, pre-solidification in the shot sleeve and during filling as well as variations in the timing of the pressure intensification. In the present work the effects of solidification during filling are discussed with emphasis on the resulting microstructures and the correlation with mechanical properties.