cementite

chemical compound

Also known as: iron carbide

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June 24, 2026

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Cementite is a hard, brittle iron carbide with the chemical formula Fe₃C. It is a key component found in steel, cast iron, and other iron-carbon alloys. In steel, carbon can exist either dissolved in iron or as a carbide, with cementite being the iron carbide form. The presence and amount of cementite significantly influence the properties of steel, contributing to its hardness. Cementite is distinct from the geological process of cementation, which involves the hardening of sediments by mineral precipitation.123

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iron processing
…carbide (Fe₃C), also known as cementite, is formed; this leads to the formation of pearlite, which in a microscope can be seen to consist of alternate laths of alpha-ferrite and cementite. Cementite is harder and stronger than ferrite but is much less malleable, so that vastly differing mechanical properties are…
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…carbide (Fe₃C), also known as cementite, is formed; this leads to the formation of pearlite, which in a microscope can be seen to consist of alternate laths of alpha-ferrite and cementite. Cementite is harder and stronger than ferrite but is much less malleable, so that vastly differing mechanical properties are…
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steel
Effects of carbon
…iron carbide (Fe₃C, known as cementite), or it can be a carbide of an alloying element such as titanium. (On the other hand, in gray iron, carbon appears as flakes or clusters of graphite, owing to the presence of silicon, which suppresses carbide formation.)
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…iron carbide (Fe₃C, known as cementite), or it can be a carbide of an alloying element such as titanium. (On the other hand, in gray iron, carbon appears as flakes or clusters of graphite, owing to the presence of silicon, which suppresses carbide formation.)
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