Question

How is cast iron different from pig iron?

Answer 1

Pig iron this form of iron is obtained from blast furnace. It contains approximately 4 % carbon and other impurties (S , P , Si, , Mn etc) in small amount.
Cast Iron this form of iron is formed by melting pig iron with scrap iron and coke using hot air blast. It has slightly lesser carbon content (3% approximately). It is extremely hard and brittle.