difference between steel and iron

Pig iron is brittle and hard, has no toughness, cannot be forged and rolled, but has good casting properties. Steel has good physical and chemical properties and mechanical properties, and can be subjected to deep processing such as drawing, pressing, rolling, punching, etc. Therefore, the use of pen irons is more extensive. Except for casting pig iron, which accounts for a very small part of the total pig iron, for the production of castings, most of the pig iron must be further smelted into steel to meet the production needs of various social and economic sectors.



Both steel and iron are iron-carbon alloys with iron as the main element and a small amount of carbon, silicon, manganese, phosphorus, sulfur and other elements. According to the carbon content and the content of other elements, it can be divided into steel and iron. The most important of these is the difference in carbon content. The level of carbon content causes changes in the state and structure of iron-carbon alloys at different temperatures, thus making steel and iron have different properties and uses. Generally speaking, iron-carbon alloys with a carbon content of more than 2% are called pig iron, and steels with a carbon content of less than 2%. Pig iron has a high carbon content and is characterized by being hard and brittle. It is mainly used for casting motor housings, gearbox housings, machine tool beds and brackets, and other mechanical parts. In the modern steel industry, 90% of pig iron is used for steelmaking. Raw materials are used, and only about 10% of pig iron is used for casting production. The process of making steel from iron requires the addition of various deoxidizers and alloying element additives, such as ferrosilicon and ferromanganese.

Steel has better comprehensive mechanical properties than iron, such as higher mechanical processing strength, toughness, good plasticity, and can be easily processed into various shapes such as plates, profiles, and wires. Has good electrical and thermal conductivity. If some alloying elements are added to steel, steel with special properties can be obtained, such as stainless steel, heat-resistant steel, acid-resistant steel, etc.