It is also known as Ductile Cast Iron, Spheroidal Graphite (S.G.) Cast Iron or High strength Cast Iron. This nodular cast iron is produced by adding magnesium to the molten cast iron.
The magnesium converts the graphite of cast iron from flake form to spheroidal or nodular form. This way, the mechanical properties are considerably improved Nodular cast iron can be produced in thicker pieces than those produced by malleable cast iron. Out standing characteristics of nodular cast iron are high fluidity, which permits the castings of intricate shapes.
This cast iron is widely used in cast parts where density and pressure tightness is a highly desirable quality y include hydraulic cylinders, valves, pipes and pipe fittings, cylinder head for compressors and diesel engines. Rolls for rolling mills and many types of centrifugally cast parts are also made of nodular cast iron.