Any of a number of alloys consisting predominantly of iron with varying proportions of carbon (up to 1.7%) and, in some cases, small quantities of other elements (alloy steels ), such as manganese, silicon, chromium, molybdenum, and nickel. Steels containing over 11–12% of chromium are known as stainless steels.
Carbon steels exist in three stable crystalline phases: ferrite has a body-centred cubic crystal, austenite has a face-centred cubic crystal, and cementite has an orthorhombic crystal. Pearlite is a mixture of ferrite and cementite arranged in parallel plates. The phase diagram shows how the phases form at different temperatures and compositions.
Steels are made by the basic-oxygen process (L–D process), which has largely replaced the Bessemer process and the open-hearth process, or in electrical furnaces.
Phase diagram for steel
- fractional quantum Hall effect
- frame of reference
- Franklin, Benjamin
- Frasch process
- Fraunhofer diffraction
- Fraunhofer lines
- Fraunhofer, Josef von
- free electron theory
- free energy
- free fall
- free space
- freeze drying
- freezing mixture
- Frenkel defect
- Frenkel-Kontorowa model
- frequency
- frequency modulation
- fresnel
- Fresnel diffraction
- Fresnel lens
- friction
- froth flotation
- frustum
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