What is Ductile Iron ? How it is made ?

Spheroidal graphite iron, also called modular cast iron, is of a higher grade because graphite is precipitated not in the form of flakes but in the form of spheroids. This can be achieved by various methods, e . g., by the addition of one of the following elements : magnesium, cerium, calcium, bismuth, zinc, cadmium, titanium or boron. Ferro - Silicon is also used as an inoculant.

Spheroidal cast iron can be producer in thicker pieces than those produced by malleable cast Iron. Outstanding characteristics of spheroidal cast iron are high fluidity, which permits the castings of intricate shapes, and an excellent combination of strength and ductility. The tensile strength of this iron is about 33 kg-f per mm2 (330 Newton per mm2). This material is also known as Ductile Iron.

Spheroidal cast iron is widely used in cast parts where density and pressure tightness is a highly desirable quality. They 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 spheroidal cast iron.

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ELECTRICAL COMPARATORS AND ITS WORKING

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Mechinopedia For Mechanical Engineers

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