Iron casting is greater than 2.1% carbon content of the iron-carbon alloys, iron casting refers to the cast iron (Part steelmaking pig iron) re- melted in a furnace, and added ferroalloy, scrap, recycled iron obtained by adjusting the composition. Addition to carbon , but also contains silicon, manganese , sulfur, phosphorus and other impurity elements, according to need, and sometimes adding some alloying elements, it is important metal material and widely used in machinery manufacturing.

Iron casting has the advantages of wear-resisting, resistance to vibration, but low strength, plasticity and toughness and weld ability is quite poor. Because iron casting with a high content of carbon and silicon , low melting point, good liquidity, it is widely used in the production of various castings. Iron casting according to chemical composition is divided into ordinary iron casting and alloy iron casting, according to the microstructure into white iron casting, gray iron casting, ductile iron casting, compacted graphite iron casting and malleable iron casting. According to the use of performance is divided into the structure of iron casting and special iron casting.

Iron casting is used early in the history of material, also is one of the cheapest metal materials, at the same time, it has many advantages, so iron casting is great important and commonly used structure materials in modern machinery manufacturing .its weight is generally accounted for 60% to 70% of the total weight of the machine . For example, in automobile engines, accounting for 80 percent of iron casting, iron casting pieces in the machine tool industry accounts for about 60-90 %.