FE-C Phase Diagrams for Engineering Students

Study the phase of iron-carbon phase using the following Fe-C Phase Diagrams which will show you the examples of the phase diagram. The Fe-C phase diagram shows which phases are to be expected at metastable equilibrium for different combinations of carbon content and temperature.

To know more about what we’re talking about, check out the first diagram below.

FE-C Phase Diagram CCT
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Study the Fe-C Phase Diagram above. Steels are alloys having elements of iron (Fe) and carbon (C). C gets dissolved in Fe during the production of steels. Pure Fe melts at a temperature of 1540 degrees C, and at this temperature, C readily dissolves into the liquid iron, generating a liquid solution. When this liquid solution solidifies, it generates a solid solution, in which the C atoms are dissolved into the solid iron.

FE-C Phase Diagram PDF
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FE-C Phase Diagram for Steel S
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The individual C atoms lie in the holes between the Fe atoms of the crystalline grains of austenite (at high temperatures) or ferrite (at low temperatures). Steels that are 100 % austenite must have temperature-composition coordinates within the area of austenite. Steels that are ferrite must have temperature-composition coordinates in the narrow region at the lower left of the Fe-C phase diagram.

FE-C Phase Diagram English
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Low FE-C Phase Diagram
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Austenite holds more C than ferrite because the holes between iron atoms are larger in the fcc structure than the bcc structure. It is important to understand the iron-carbon phase transformations. All of the diagrams are printable in high quality, so just click the save menu and you can print it out from your browser!