SG Cast Iron 420/12

Spheroidal graphite cast iron 420/12 (BS EN 1563:1997), also known as ductile cast iron, is a type of cast iron that has been treated while molten with an element such as magnesium or cerium to induce the formation of free graphite as nodules or spherulites. The rounded shape of the nodules creates less stress points than the flat graphite flakes found in grey iron, this inhibits the creation of cracks and provides enhanced ductility. This nodular graphite structure inhibits the creation of linear cracks hence the ability to withstand distortion. In addition, ductile iron provides a unique combination of strength, wear resistance, fatigue resistance, and toughness. Products cast using ductile iron include valves, impellers, winch drums, separator body liners, etc.

For detailed chemical composition, typical mechanical properties and comparative specifications please view the SG420/12 data sheet by filling out the form below.

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    All information in our data sheets and website is indicative only and is not intended to be a substitute for the full specification from which it is extracted. It is intended to provide typical values to allow comparison between metal alloy options rather than a definitive statement of mechanical performance or suitability for a particular application as these will vary with temperature, product type and product application. It is presented apart from contractual obligations and does not constitute any guarantee of properties or of processing or application possibilities in individual cases. Our warranties and liabilities are stated exclusively in our terms of trading.