Carbon steel

Steel in which the main interstitial alloying constituent is carbon

Carbon steel (US) or non-alloy steel (Europe) is a steel with carbon content from about 0.05 up to 2.1 percent by weight. The definition of carbon steel from the American Iron and Steel Institute (AISI) states: no minimum content is specified or required for chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium, zirconium, or any other element to be added to obtain a desired alloying effect, or the specified minimum for copper does not exceed 0.40%, or the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 1.65%, silicon 0.60%, copper 0.60%. The addition of significant amounts of other metals, such as nickel, chromium, vanadium, molybdenum, changes the materials definition from carbon steel to alloy steel.

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