It is one of the main elements added in the manufacture of steel.
It neutralizes the sulfur, and forms manganese sulphides avoiding the formation of iron sulphides. It is also beneficial because it acts as a deoxidizer.
As an alloying element in a percentage of up to 1.6% it provides carbon steels with greater tensile strength, yield strength and hardenability. In steels alloyed with manganese up to 3% it confers undeformability, and in steels with high resistance to wear it is used in percentages up to 12%.