Cast Iron

Cast Iron is an iron-carbon alloy with a typical carbon content of 3.0-4.5 wt.%. Also Si (0.5-3.5 wt.%) and small amounts of Mn, S and P are always present. The main advantages of cast iron are its low price and the ability to make products of a complex shape in a single production step. Furthermore, cast iron offers a reasonable resistance against corrosion. In general, the mechanical properties are lower than those of cast or wrought steels, especially when loaded in tension. In compression high loads can be supported. The mechanical properties of cast iron depend on the morphology of the carbon. This morphology depends on composition and process parameters. In grey cast iron the carbon is present in plates (lamellar) of pure graphite. In white cast iron carbon is incorporated in compound with iron: Fe3C (cementite). In nodular cast iron the carbon is present in sphere shaped graphite particles (nodulae). Nodular cast iron has better properties than lamellar, especially tensile strength and strain.