Carbon Steel is generally a reference for all non stainless steels. Carbon steel has a higher carbon content up to 2.1% against the total weight. In carbon steels the alloying contents like cobalt, chromium, nickel, molybdenum, titanium, niobium, tungsten, vanadium and zirconium is not specified. Carbon steels tend to become harder and stronger with heat treatment, while losing ductility. The high carbon content in carbon steel also makes it less weldable, regardless of any loss of weldability due to heat treatment.
Low-carbon steel or mild steel or plain steel is a type of carbon steel. The carbon content in mild steel is approximately 0.5-0.25%. It is also one of the most commonly used steels because of its low price and properties that make it usable in many applications. The surface hardness of low-carbon steel can be increased through carburizing. The tensile strength of low-carbon steel is low when compared to other steel types. Cold-forming in low-carbon steels is easier due to the lesser carbon content in the steel.