3. Different types of steel

3.1 Steel properties

It is estimated that nearly 98% of the world's steel production uses iron ore as a raw material. One of the reasons for this high proportion is that steel is more versatile than cast iron. It is highly resistant to deformation by compression or stretching, whether hot or cold, and it is also very easily hardenable, i.e. it can be made very hard by heating it to a high temperature (above the austenitization transformation point) and then cooling it rapidly, either by immersing it in a liquid or simply in air, as is the case for self-hardening steels, for example.

Steel is an iron alloy containing less than 2% carbon. It can be classified according to its carbon content. High-carbon steels are used for their high hardness, while low-carbon...