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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. From Wikipedia under the
GNU Free Documentation License How are ferrite, cementite and pearlite formed? Q. How are ferrite, cementite and pearlite formed? Asked by devilblues - Sat Jul 14 07:50:16 2007 - - 1 Answers - 0 Comments A. The three phases, ferrite, cementite and pearlite are thus the principle constituents of the infrastructure of plain carbon steels, provided they have been subjected to relatively slow cooling rates to avoid the formation of metastable phases. Answered by Dr.Shashikant - Sat Jul 14 07:56:52 2007 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 From Yahoo Answer Search: "Cementite"  news.google.com Examiner.com The 'cooked'-on pad material is called cementite , and it is pretty much permanent, where no amount of resurfacing can remove it. ... news.google.com Hindu "The presence of high amount of iron carbide also called ' cementite ' renders these rails susceptible to corrosion," he explained. ... and more » From Google News Search: "Cementite"  cashenblades.com 186px x 199px | 23.40kB [source page] takes in steel cast iron and other iron carbon alloys It is a compound of 93 33 iron and 6 67 carbon by weight but occurs in alloys in the form of proeutectiod cementite above 83 C Back to Info Index  leeds.ac.uk 398px x 283px | 29.80kB [source page] Low magnification Bright Field TEM micrographs of the magnetic domain boundaries within the ferritic alpha regions of the duplex ferritic alpha austenitic gamma microstructure of a From Yahoo Image Search: "Cementite"  iwanpw.blogspot.com iwanpw Fri, 14 Mar 2008 06:40:00 GM In the so-called 'inverse bainite' which is in the steels hypereutectoid is . cementite. which is the first phase of the form (Hillert, 1957). A plaque-like spine of . cementite. grows directly from austenite (Henemann, 1970) and becomes ...  stylishasiankids.blogspot.com Jon Fri, 08 Feb 2008 01:21:00 GM peter paufler and his colleagues discovered the carbon nanotubes after dissolving the material into hydrochloric acid, ironically to research another material known in the swords called . cementite. nanowires. because carbon nanotubes are ...  autocostruzione.forumcommunity.net bekka21 Wed, 16 Apr 2008 11:35:19 GM 16/04/2008, 13:35:19 Ultimo msg di: bekka21. From Google Blog Search: "Cementite" |
