Porosity, what is it?
Even with careful production techniques, castings made of grey iron, copper, aluminium and magnesium alloys often turn out porous. Casted parts that were meant to be pressure tight can no longer be used as intended, e.g. as motor parts, oil pans, brake cylinders, pump casings, filter parts or valves.
Porosity can appear because of alloy composition, mould design, melting temperature. It can also appear in the cooling process after casting - but to notice: porosity cannot always be avoided!