4130 Steel

4130 noun. American
taken from the AISI 4-digit code system

4130 is a code of the American Iron & Steel Institute and defines the approximate chemical composition of the steel

This is a type of CrMo (chromoly) – the number is a way of defining which metals are added to the steel to make it stronger. The number is globally recognised as a metallurgical type definition, which has strict standards to which the steel must comply.

The “41” denotes a low alloy steel containing nominally 1 percent chromium and 0.2 percent molybdenum (hence the nickname “chromoly”). The “30” denotes a carbon content of 0.30 percent. In addition, as normal constituents of plain carbon and low alloy steels, there will be around 0.2-0.5 percent silicon, 0.5-1.0 percent manganese, and well under 0.1 percent of each of a dozen or so other elements whose presence is unavoidable, in a few cases deliberate, and generally not harmful. The remaining 97-98 percent is iron (Fe).

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4130, chromoly, CrMo, noun.,  american origin, AISI 4-digit code, Steel, Materials, BMX, Single Speed, Road,

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