The Structure of Cementite

H. K. D. H. Bhadeshia

Cementite has an orthorhombic lattice with approximate parameters 0.45165, 0.50837 and 0.67297 nm. There are twelve iron atoms and four carbon atoms per unit cell, corresponding to the formula Fe3C.

This figure shows the crystal structure of cementite. The purple atoms represent carbon. Each carbon atom is surronded by eight iron atoms. Each iron atom is connected to three carbon atoms. These connections are not obvious from this figure since only the atoms within the unit cell are illustrated.

cementite

This figure shows the coordination polyhedron, in which eight iron atoms surround a carbon atom. The polyhedron consists of a square base and eight triangles.

cementite

The polyhedra are connected at their corners and edges. This image is created using the Crystalmaker library.

cementite.

Bulk samples of pure cementite

Ceramic, cementite and coffee

Bulk sample of pure cementite provided to Harry by Professor Minoru Umemoto of Toyohashi University in Japan, for experiments on hydrogen to be done by Miles Stopher
Ceramic, cementite and coffee

Bulk sample of pure cementite provided to Harry by Professor Minoru Umemoto of Toyohashi University in Japan, for experiments on hydrogen to be done by Miles Stopher

Movies

Unit cell of cementite
Polyhedra
Polyhedra and relation with unit cell

Effect of Silicon on Cementite Precipitation

Other Aspects of Cementite

Other Sources on Carbides

Research publications

Review: theory of carbide precipitation

Review

Carbide chemical compositions

allotriomorphic



Cementite Crystal Structure Projections

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Cementite
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Cementite
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Cementite
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Cementite
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Cementite
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Cementite
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Cementite
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Cementite - only the iron atoms are illustrated
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Cementite - only the iron atoms are illustrated
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Cementite - only the iron atoms are illustrated



Carbide and Carbon Building in Chicago

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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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Carbide and carbon building, Chicago
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