Analyze of the possible causes of porosity type deffects in aluminium high pressure diecast parts

Die casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mold cavity. The mold cavity is created using two hardened tool steel dies which have been machined into shape and work similarly to an injection mold during the process. Most die castings are made from non-ferrous metals, specifically zinc, copper, aluminium, magnesium. Depending on the type of metal being cast, a hot- or cold-chamber machine is used. Die castings are characterized by a very good surface finish (by casting standards) and dimensional consistency. The most common deffect that appear in castings is the porosity type of deffect, which can be gas porosity, shrinkage porosity or leaker.