It is the iron that displays white fractured surface due to the presence of cementite.
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For steels that have more than 0.8% carbon the cooled structure takes the form of pearlite and cementite.
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Pearlite is a mixture of ferrite and cementite formed when steel or cast iron are manufactured and cooled at a slow rate.
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Tungsten interferes with the formation of cementite, allowing martensite to form with slower quench rates, resulting in high speed steel.
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Its properties were unique due to the special smelting and reworking of the steel creating networks of iron carbides described as a globular cementite in a matrix of pearlite.
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Much effort was expended on consideration of the austenite-martensite-cementite phases found in the iron-carbon phase diagram that underlies steel production.
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A chemical compound that is a constituent of steel and cast iron; very hard and brittle
Cementite, also known as iron carbide, is a chemical compound of iron and carbon, with the formula Fe3C (or Fe2C:Fe). It is 6.67 percent carbon and 93.3% iron. It has an orthorhombic crystal structure.. ...
Iron carbide, Fe3C, a hard brittle, crystalline compound observed in the microstructure of iron-base alloys.
This is a carbon rich steel also known as iron carbide (Fe3C). In carbon steel, it either forms from austenite while cooling or from martensite during tempering. (top)
FE3C Iron carbide. A hard substance found in cast iron.
A form of iron carbide (Fe3C) contained in carbon and alloy steels.