High carbon steel, abbreviated as HCS, is primarily an alloy of iron and carbon, with carbon being the most critical alloying element, typically ranging from 0.6% to 1.0% (though sometimes up to 1.5%). This elevated carbon percentage significantly increases the steel's strength, hardness, and wear resistance, making it an excellent choice for applications requiring durability and the ability to hold a sharp edge. However, this increased hardness also leads to lower ductility and malleability, meaning high carbon steel is more brittle and can be challenging to machine, cut, and form compared to lower carbon steels. Despite its susceptibility to rust due to the lack of significant chromium content (unlike stainless steel), its superior mechanical properties make it widely used for cutting tools, springs, high-strength wires, and various components in industries like automotive, manufacturing, and construction.
This high carbon content is what imparts its characteristic strength, hardness, and wear resistance. In addition to iron and carbon, high carbon steel also contains other elements, most notably manganese, usually in amounts from 0.3% to 0.9%, which helps improve hardenability and acts as a deoxidizer during production. Other elements like silicon (typically 0.1% to 0.4%) are often present as deoxidizers and can enhance strength and elasticity. While high carbon steel is defined by its elevated carbon content, some variations may include small amounts of other alloying elements like chromium, nickel, molybdenum, or vanadium to further enhance specific properties such as corrosion resistance, toughness, or heat resistance, effectively creating "alloyed carbon steel" or "tool steel" categories. However, in plain high carbon steel, these additional elements are usually present only in trace amounts or not at all.
