Editing Cast iron (section)

===Ductile cast iron===
{{Main|Ductile cast iron}}

Developed in 1948, '''''nodular''''' or ''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. Along with careful control of other elements and timing, this allows the carbon to separate as spheroidal particles as the material solidifies. The properties are similar to malleable iron, but parts can be cast with larger sections.{{Citation needed|date=March 2021}}