The difference between cast iron and steel

Steel is an alloy of iron with greater than 0.02 % carbon but less than 2%, and cast iron is an alloy of iron containing a even more carbon between 2 and 4%.

Cast iron is cheaper than steel, and has a low melting point with the ability to mold easily.

Cast iron is a group of iron-carbon alloys with a carbon content greater than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its colour when fractured: white cast iron has carbide impurities which allow cracks to pass straight through, grey cast iron has graphite flakes which deflect a passing crack and initiate countless new cracks as the material breaks, and ductile cast iron has spherical graphite “nodules” which stop the crack from further progressing.

Carbon (C) ranging from 1.8 to 4 wt%, and silicon (Si) 1–3 wt%, are the main alloying elements of cast iron. Iron alloys with lower carbon content are known as steel.

Cast iron is made from pig iron, which is the product of melting iron ore in a blast furnace.

铸铁 – zhùtiě чугун Cast iron