Difference Between Steel and Pig Iron

Depending on the content of carbon, all iron alloys are divided into steels and pig irons. If the carbon content is less than 1.7-2.0%, iron alloys are called 'steels'; with higher carbon concentrations, they are called pig irons. When the carbon content is from 1.7% to 2.8-3.0% they are called steely pig irons, and common pig irons when they contain more carbon.

Steel has a high ductility at high temperatures and can be readily forged or rolled on heating. Pig irons do not possess such valuable properties. On the other hand, they have a substantially lower melting point than steels and possess better castings properties, which is used widely in foundry practice. In modern iron and steel making, steels, as a rule, contain not more than 1.2 % C and pig irons, from 3.5% to 4.5% C.