A Possible Mechanism for the Formation of Exploded Graphite in Nodular Cast Irons

Abstract:

In hypereutectic nodular cast irons, primary precipitation of graphite may lead to graphite flotation in thick section castings. Graphite degeneracy such as so-called exploded graphite is then often associated with this flotation phenomenon and it appears as precipitates where the nodular form is replaced by star-like or flower-like shape. It has been reported that exploded graphite develops after the primary spheroidal nodules have reached some tens of microns in diameter. In this contribution, a model for this transition is presented.

• Periodical: Materials Science Forum (Volumes 790-791)
• Pages: 435-440
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.790-791.435
• Online since: May 2014
• Authors: Roxana Gerghu, Lena Magnusson Åberg, Jacques Lacaze
• Keywords: Exploded Graphite, Graphite Degeneracy, Primary Growth, Spheroidal Graphite

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