Eutectoid

A eutectoid is the mostly lamellar layered product of the disintegration of a crystalline phase into two crystalline phases. This phase transition occurs through diffusion in the solid state, while a eutectic arises from a liquid phase. An example is the conversion of iron - carbon - mixed crystals to pearlite (see also iron-carbon phase diagram ). ${\displaystyle \gamma \rightarrow \alpha +\beta .}$

The eutectoid in the phase diagram is the isothermal line through the eutectoid point , with the composition of which the phase has the coldest (lowest in terms of temperature) stability limit, corresponding to the eutectical through the eutectic point . ${\displaystyle \gamma }$

literature

• Franz Roll (Hrsg.): Manual of the foundry technology. Volume 1 / Part 2 Materials II, Springer Verlag, Berlin Heidelberg 1960.
• Stephan Hasse: Foundry Lexicon. 19th edition, Verlag Schiele & Schön, Berlin 2007, ISBN 978-3-7949-0753-3 .

Web links

• Iron-carbon diagram on Maschinenbau-Wissen.de (accessed on January 18, 2016)
• More on phase diagrams (accessed January 18, 2016)
• The state diagram iron - carbon (accessed on January 18, 2016)