Steel is an iron alloy with an amount of carbon that can vary between 0.03% and 1.075% by weight of its composition, depending on the steel grade.
Steel is not the same as iron and the two materials should not be confused. Iron (Fe) is a relatively hard and tough metal, with a melting temperature of 1535 °C and a boiling point of 2740 °C.
The main difference between iron and steel is in the percentage of carbon: steel is iron with a percentage of carbon between 0.03% and 1.075%.
Steel preserves the metallic characteristics of iron in its pure state, but the addition of carbon and other elements, both metallic and non-metallic, improves its physicochemical properties, especially its strength.
There are many types of steel depending on the elements that are present. Each type of steel will allow different applications and uses, which makes it a versatile and widely used material in modern life, where we can find it widely on avenues and bridges.
The properties of steel depend on its chemical composition and the type of treatment applied. The most important characteristics that all steels share are as follows:
- Hardness: it is difficult to penetrate.
- Strength: it is able to resist twisting, compression, traction and bending without deforming.
- Malleability: withstands forces without breaking.
- Ductility: allows it to be deformed at high temperatures into conductive wires and threads or into thin sheets.
The types of treatment that steels are subjected to enhance some of their properties are:
- Heat treatment: application of heat.
- Thermochemical treatment: use of chemicals and heat.
- Surface treatment: coatings of other materials.
- Mechanical treatment: introduction in hot and cold environments.
- Carbon steel: it is one that is composed only of iron and carbon.
Types of Steel
The types of steels are classified according to their composition. Some of them are:
- Special steel: it combines iron, carbon and other elements such as aluminum, manganese among others.
- Alloy steel: It is an alloy that includes silicon or nickel used in tubes and valves, pumps and automotive parts thanks to its resistance to corrosion of liquids with high pH (neutral and alkaline). It is classified, in turn, into gray cast iron and nodular cast iron.
- Stainless steel: the composition of this steel includes chromium which makes it resistant to corrosion and oxidation. In addition, it has a more attractive appearance since it is polished.
- High speed steel: this type of alloy contains tungsten used to make high speed cutting tools used in factories.
The two main components of steel are found in abundance in nature. Steel can be recycled indefinitely without losing its attributes, which favors its large-scale production. This variety and availability makes it suitable for numerous uses such as the construction of machinery, tools, buildings, electrical structures and public works, in aeronautics, in the automotive industry, in greenhouses, in medical instruments, in the furniture sector among others. Contributing to the technological development of industrialized societies, as no material can match it when it comes to resistance to impact or fatigue.