Cementite or iron carbide is a chemical compound with the formula Fe3C (or Fe2C:Fe), and an orthorhombic crystal structure. It is a hard, brittle material, normally classified as a ceramic in its pure form, though it is more important in metallurgy.

It forms directly from the melt in the case of white cast iron. In carbon steel, it either forms from austenite during cooling or from martensite during tempering. An intimate mixture with ferrite, the other product of austenite, forms a lamellar structure called pearlite. Much larger lamellae, visible to the naked eye, make up the structure of Damascus steel.

Cementite changes from ferromagnetic to paramagnetic at its Curie temperature of approximately 480 K.

A natural iron carbide (containing minor amounts of nickel and cobalt) occurs in iron meteorites and is called cohenite after the German mineralogist Emil Cohen, who first described it.

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Wed Jan 20 02:04:17 2010

what is the difference between primary ,secondary & tertiary cementite?
Q. what is the difference between primary ,secondary & tertiary cementite?
Asked by rajev v - Mon Jul 2 05:07:03 2007 - - 2 Answers - 0 Comments

A. IDK
Answered by Cin Reaper - Tue Jul 10 04:11:06 2007

Why is cementite stronger than ferrite?
Q. regarding structure, factors concerned...
Asked by hello!!!! - Mon May 18 02:59:00 2009 - - 1 Answers - 0 Comments

A. It isn't. Ferrite a A LOT stronger then Cementite (Iron Carbide) in terms of tensile strength (which is generally how such things are measured). Ferrite has a tensile strength of around 280 N/mm^2 Cementite has a tensile strength of around 35 N/mm^2
Answered by GEadon - Mon May 18 19:41:33 2009

Define : Austenite, Ferrite,Cementite
Q. Define : Austenite, Ferrite,Cementite
Asked by ankit d - Sun Aug 3 10:07:38 2008 - - 2 Answers - 0 Comments

From Yahoo Answer Search: "Cementite"
Sat Jul 11 22:23:47 2009

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rocketmadness.com
you think you know alot about brakes? no you dont!

ryan_1000R

Fri, 10 Nov 2006 21:11:30 GM

when this local temperature reaches around 1200 or 1300 degrees f. the cast iron under the deposit begins to transform into . cementite. (an iron carbide in which three atoms of iron combine with one atom of carbon). . cementite. is very hard ...

metallography
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metallography

Felix

Wed, 04 Apr 2007 15:36:00 GM

in steel there is ferrite (iron with a little bit of c dissolved) and metastable . cementite. fe3c. those are probably the two phases above but it's hard to really see something. we etched the cast iron with nital solution (nitric acid in ...

Variety and Material Quality of Rolls 4
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Variety and Material Quality of Rolls 4



Sat, 12 May 2007 08:08:33 GM

pearlite+. cementite. +small percentage graphite. NiCrMo indefinite chilled cast iorn rolls . pearlite+. cementite. +small percentage graphite. NiCrMo indefinite chilled cast iron rolls . fine pearlite+. cementite. +small percentage ...

From Google Blog Search: "Cementite"
Sat Jul 11 22:23:13 2009

There's no such thing as 'warped' brake rotors - Examiner.com
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There's no such thing as 'warped' brake rotors

Examiner.com

The 'cooked'-on pad material is called cementite , and it is pretty much permanent, where no amount of resurfacing can remove it. ...
Vacuum toilets on trains will also save the rails below - Hindu
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Vacuum toilets on trains will also save the rails below

Hindu

"The presence of high amount of iron carbide also called ' cementite ' renders these rails susceptible to corrosion," he explained. ...



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From Google News Search: "Cementite"
Sat Jul 11 22:20:20 2009

cementite diffraction gif
msm.cam.ac.uk
cementite diffraction gif
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X ray diffraction pattern of cementite

SteelMicrostructureCementite jpg
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SteelMicrostruc​tureCementite jpg
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Steel Micro Structure Cementite

3 jpg
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Up Next > Fe 1 75C 2Si 1Mn wt Austenitised at 1393 K for 4 h and quenched into water Shows fine pearlite growing from proeutectoid cementite at the austenite grain boundaries The white phase is

From Yahoo Image Search: "Cementite"
Sat Jul 11 22:20:37 2009