Comparison of Steel with Aluminum...

Comparison of Steel with Aluminum Steel is an alloy of iron and other elements, primarily carbon. It is most commonly produced by reduction of iron ore. Carbon, the most common alloying material in steel, acts as a hardening agent, preventing any dislocations within the iron atom crystal lattice from separating and sliding past each other thus making steel more durable. By varying the amount of alloying elements and the form of their presence in the steel, one can control qualities such as hardness, ductility, and tensile strength of steel. Though, steel has been known to be around since 4,000 years ago, it was not widely produced until the 17th century. Its mass production started due to the introduction of the Bessemer process during 1850s. This process made steel production cheaper, efficient and easier. Production of steel is a two stage process. First iron is produced by reduction of iron ore. This iron is then converted into steel by oxidizing the impurities. (Fig 1) Fig 1 Production process of steel Steel is widely used in construction and other applications because of its high tensile strength and low cost. Iron is the basic component of steel. Composition of steel mainly consists of iron and other elements such as carbon, manganese, silicon, phosphorus, sulphur, and alloying elements. A large number of elements in wide ranging percentages are used for the purpose of alloying of steels. Variations in chemical composition of steels are responsible for a great variety of steel grades and steel properties. Each element that is added to the basic steel composition has some effect on the properties of the steel and how that steel reacts to the processes of working and fabrication of steels. The chemical composition of steel also determines the behaviour of steel in...