Machining gray iron, ASTM A48

Gray Iron

Also called grey cast iron, gray iron is a kind of cast iron with a graphitic microstructure. It has high thermal conductivity, good machinability and excellent damping capacity. Unfortunately, because of its low ductility and tensile strength, it has very little impact and shock resistance. It does, however, have good corrosion resistance because of its silicon content, which can occupy up to 6 to 10% of the content of gray iron. Because of its low cost of production and attractive properties, gray iron is one of the most commonly used ferrous alloys.

Pro Tip: That being said, there are a number of instances where ductile iron would be preferred for a given application. To learn more, read “The Differences Between Ductile Iron and Gray Iron.”

We pour several grades of ductile iron including:

Possible Applications for Gray Iron


  • Frames

  • Gear Boxes

  • Cable Drums

  • Pumps

Contact us today to discuss your specific application and the alloy you require.

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