Carbon Steels
Carbon Steels are used extensively in tool construction. Carbon steels are those steels which only contain iron and carbon, and small amounts of other alloying elements. Carbon steels are the most common and least expensive type of steel used for tools. The three principal types of carbon steels used for tooling are low carbon, medium carbon, and high carbon steels. Low carbon steel contains carbon between 0.05% and 0.3%. Medium carbon steel contains carbon between 0.3% and 0.7%. And high carbon steel contains carbon between 0.7% and 1.5%. As the carbon content is increased in carbon steel, the strength, toughness, and hardness are also increased when the metal is heat treated.
Low carbon steel are soft, tough steels that are easily machined and welded. Due to their low carbon content, these steels cannot be hardened except by case hardening. Low carbon steels are well suited for the following applications: tool bodies, handles, die shoes, and similar situations where strength and wear resistance are not required.
Medium carbon steels are used where greater strength and toughness is required. Since medium carbon steels have a higher carbon content, they can be heat treated to make parts such as studs, pinds, axles, and nuts. Steels in this group are more expensive as well as more difficult to machine and weld than low carbon steels.
High carbon steels are the most hardenable type of carbon steel and are used frequently for parts where wear resistance is more important factor. Other applications where high carbon steels are well suited include drill bushings, locations, and wear pads. Since the carbon content of these steels is so high, parts made from high carbon steel are normally difficult to machine and weld.
