Image icon  Fe, C 0.8 (wt%) steel, eutectoid transformation, spheroidised

Use this resource: Use this resource icon
Link to this page:
View at:            
Resource type: Image
Description: This steel is of the eutectoid composition. Once the temperature is lowered below the eutectoid temperature, the austenite phase tends to undergo a eutectoid transformation (γ to α + Fe3C). The resultant microstructure, known as pearlite, comprises alternate lamellae of cementite and ferrite. Subsequent to casting, the alloy was normalised (annealed) just below the eutectoid temperature, in order to induce the carbides to take a spherical appearance, which results in the steel becoming softer and more ductile. This is known as spheroidisation. The changes to the morphology of the cementite are visible in this micrograph, but are clearer at higher magnification (see micrograph 267).
Keywords: alloy • carbon • iron • metal • normalising • spheroidised • steel
Categories: Science approaches > Microstructure
Materials > Metals & alloys > Carbon steels
Processes > Thermal treatments > Annealing
Testing, analysis & experimentation > Metallography
Scale > Micro
Created by: DoITPoMS, University of Cambridge
Dr R F Cochrane, Department of Materials, University of Leeds
Published by: DoITPoMS, University of Cambridge
License: This resource is released under the Creative Commons Attribution Non-Commercial Share Alike license (2.0 UK: England & Wales).
Creative Commons Attribution Non-Commercial Share Alike logo
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
  • noncommercial – You may not use this work for commercial purposes.
  • share alike – If you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one.
View the full legal code here.
Date created: 04 September 2002
Date added: 21 August 2009
Resource ID: 1303