The main difference between cast iron and pig iron is that cast iron is a hard and brittle alloy of iron and carbon whereas pig iron is a semi-fused alloy of iron and carbon. Furthermore, cast irons are used for making pipes, machine parts, cylinders for engines etc. while pig irons are used for making tools and machinery.
Cast Iron Definition
Cast iron is an alloy containing 1.8–4% of carbon, depending on the type of cast irons, 1–3% silicon with small amounts of manganese and sulfur. This material has a relatively lower melting point than purer forms of metals like steel alloys or copper alloys. Therefore, people can mold this material in any shape using special molds. Moreover, it is important to note that this material is extremely hard but also very brittle compared to other metals such
Pig Iron Definition
Iron is an important chemical element since the early ages of humanity. It has many important uses in our daily life. Therefore, it occurs in many forms such as cast irons and pig irons. The key difference between cast iron and pig iron is that the cast iron is a hard and brittle alloy of iron while the pig iron is a semi-fused alloy of iron.
Pig iron is the raw material used to make cast iron. Pig iron is made of about 92-94% iron, 3-4% carbon, and 1-2% manganese along with smaller amounts of other impurities. Cast Iron is made by re-melting pig iron, often along with substantial quantities of scrap iron, scrap steel, limestone, carbon (coke) and taking various steps to remove undesirable contaminants. Pig iron has a very high carbon content, typically 3.5–4.5%, which makes it very brittle and not useful directly as a material except for limited applications.
Cast iron VS Pig iron
Cast Iron: Carbon content is 2–4%. It contains lesser amount of carbon than pig-iron and can be moulded into any shape.
Pig Iron: Carbon content is 4–5%. It cannot be moulded because it has a higher amount of carbon than cast-iron.
Pig iron has a very high carbon content, typically 3.5–4.5%, which makes it very brittle and not useful directly as a material except for limited applications. The traditional shape of the molds used for casting pig iron that gives it the name “pig iron”, and today they are called “pigs” in the metallurgy field.
Cast iron products are made directly from molten pig iron or from scrap melting in electric arc furnace. It can be casted into various shapes by pouring liquid pig iron into molds, or by removing some of the carbon and silicon by oxidation, forming a slag and extracting it through holes in the bottom of the furnace to leave an iron lump with a lower carbon content called “cast iron” (but still higher than steel).