The Difference Between Pig Iron and Cast Iron

Steel is produced from pig iron and boasts high mechanical strength and toughness, as well as special properties such as heat resistance, corrosion resistance, and wear resistance. Iron is extremely abundant in nature, accounting for 5% of the Earth's crust elements and ranking fourth among the Earth's materials. The iron element is highly reactive and readily combines with other substances. The term "steel" is commonly used to refer to both steel and iron, which are distinct from each other. Steel is primarily composed of two elements: iron and carbon, where the iron and carbon elements form a compound known as iron-carbon alloy. The carbon content significantly influences the properties of steel and iron; once the carbon content reaches a certain level, it can cause a qualitative change. Pure iron, composed of iron atoms, contains very few impurities. The carbon content is the main criterion for distinguishing between cast iron and steel. Cast iron has a carbon content greater than 2.0%, while steel has a carbon content less than 2.0%. Cast iron is hard and brittle, with little plasticity. Pure iron and steel not only have good plasticity but also possess excellent physical and chemical properties such as high strength, good toughness, high-temperature resistance, corrosion resistance, ease of processing, impact resistance, and ease of refining, making them widely utilized.