ITEM NAME : SG IRON CASTING TYPE : ALL GRADES OF SG IRON CASTINGS USED IN ( TEXTILE / AUTOMOBILE / VALVE / GENERAL EBGINEERING INDUSTRIES )' ductile cast iron has its graphite in the form of very tiny nodules with the graphite in the form of concentric layers forming the nodules. As a result, the properties of ductile cast iron are that of a spongy steel without the stress concentration effects that flakes of graphite would produce. The carbon percentage present is 3-4% and percentage of silicon is 1.8-2.8%.Tiny amounts of 0.02 to 0.1% magnesium, and only 0.02 to 0.04% cerium added to these alloys slow the growth of graphite precipitates by bonding to the edges of the graphite planes