Silicon

It is present in all steels but is added up to 5% in steels utilized as laminates in transformers, motors and generators. For giving toughness it is a significant constituent in steel utilized for spring, chisels and punches. This has a good effect in heel that combines with free O2 forming Si02 increasing soundness and strength of steel castings as up to 0.5%.

Manganese

12% to 14% of Mn produces extremely tough, wear resistant and nonmagnetic steel named as Hatfield Steel. This is important ingredient of free cutting steel upto 1.6%. Mn combines along with S, forming MnS. For this reasons Mn must be 3 to 8 times the S. M, is effective in increasing harden-ability and hardness.