Details
Material hierarchy: Metal - Ferrous metal - Cast iron
This cast iron has less carbon and silicon than gray cast iron. It is formed by more rapid cooling of the molten metal after pouring, thus causing the carbon to remain chemically combined with iron in the form of cementite (Fe3C), rather than precipitating out of solution in the form of flakes. When fractured, the surface has a white crystalline appearance that gives the iron its name. Owing to the cementite, white cast iron is hard and brittle, and its wear resistance is excellent. Strength is good, with a tensile strength of 276 MPa (40,000 lb/in2) being typical. These properties make white cast iron suitable for applications where wear resistance is required. Railway brake shoes are an example.