Advancements in High Pressure Die Casting of Magnesium

The high pressure die casting (HPDC) process is characterized by rapid die filling and a subsequent rapid cooling of the molten metal. These characteristics are favourable for magnesium die casting alloys. Due to the high cooling rate the microstructure formed reveals a fine dendrite and grain structure, which in turn leads to substantial hardening and improved ductility. Hydro Competence Centre for Magnesium has studied the HPDC process in a 420 tons die casting machine dedicated for research work. In the present paper the correlation between the thermal conditions through the process and the resulting microstructure and the mechanical properties in the casting is discussed. The effect of vacuum assisted die filling will also be discussed.