Adding a small amount of carbon to iron alters its properties significantly. Carbon strengthens iron by forming interstitial solid solution within the crystal lattice, increasing hardness and wear resistance. This change makes the iron-carbon alloy, known as steel, tougher and more durable. Depending on carbon content, steel’s ductility and malleability vary, allowing it to be shaped for various applications. However, high carbon content may reduce corrosion resistance. Overall, carbon addition to iron enables the creation of steel with a broad range of properties, making it one of the most versatile materials in industry.