Chromium is used to make stainless steel with chromium levels of over 11%, making metals corrosion resistant. It increases the metal's hardness, tensile strength, toughness, and wear resistance of a metal.
Manganese can be used as an alloying element to prevent iron sulfides from forming, as well as to increase the strength at high temperatures and improve ductility and wear resistance. Manganese improves metal's stability and hardenability.
Nickel, when used with other elements, can increase ductility and corrosion resistance. For example, a mix of 18% chromium and 8% nickel creates extremely durable stainless steels.
Silicon can be used to increase the magnetic properties of a metal as well as improving strength and providing elasticity for applications like springs.
Titanium can be used to improve the strength and corrosion resistance of a metal, as well as limiting the austenite grain size.
Vanadium carbides also limit the grain size of a metal, increasing the ductility of the alloyed material. Vanadium also improves the strength, hardness, wear and shock impact resistance. However, if used in quantities that are too high it can have a negative impact on material properties.
Molybdenum offers a good effect on steel alloys operating at high temperatures. It not only improves mechanical properties, but also provides higher resistance to rust and corrosion, and amplifies the effects of other alloying elements.
Cast iron is produced when a carbon content of 1.5-4% is alloyed with iron. Other elements including silicon, manganese, sulphur and phosphorus will be present, but only in small quantities. Cast iron is brittle, but has a good wear resistance due to its hardness. It is also easy to cast, relatively cheap, has high compressive strength, and a low melting point.