An alloy of iron and carbon, with a carbon content between about 0.1 and 2.0%. Modern alloy steel can include even more carbon, as well as a number of metals, such as chromium, nickel, manganese, titanium, vanadium, and others. A tough, malleable alloy of iron and carbon, with carbon content up to about 1.8%. Heat-treatment and alloying elements including manganese, nickel, chromium, molybdenum, and tungsten allow a range of properties to be achieved. Steel is distinguished from wrought or cast iron by its carbon content- wrought iron has less carbon than steel (0-0.2% carbon), whereas, cast iron has more (1.5-5%). Cast iron can be made into steel by removing carbon, and wrought iron can be made into steel by adding it. In practical use, however, steel is defined by the blacksmith as an iron alloy that hardens when it is heated and quenched. Other terms/types include:
Dead mild steel: 0-0.1% carbon
Mild steel: 0.1-0.25% carbon
High tensile steel: produced by modifying chemical content or by thermo-mechanical treatment
Acid steel: produced from a furnace with silica-based acid lining which does not remove the phosphorus from phosphoric iron-ore, resulting in brittle steel
Basic steel: produced from a furnace with a dolomitic limestone lining which reacts with phosphorus, allowing use of phosphoric iron ores to product good quality steel
Stainless steel: A range of corrosion-resistant chromium-nickel alloys of steel developed in the early 20th century. For constructional applications 18% chromium and 8% nickel alloys are most common, known as 18/8 austenitic steel.