The Experimental Study of Nodular Cast Iron Volume Changes during Solidification

Abstract:

The volume changes during solidification of Nodular Cast Iron (NCI) in the sand mold studied using Linear Variable Differential Transformer (LVDT). Both hypo- and hyper-eutectic compositions are considered by adjusting the carbon fraction in the composition during the experimental studies. The microstructural analysis and measurements are taken from the samples to evaluate the different phases present, the nodule count and size distributions. At the beginning of solidification, the experimental result shows the volume change is negligible. During the eutectic growth, the samples expand until the end of solidification. The displacement measurement shows the expansion continued when solidification finished. The volume change studies during solidification indicate that as the carbon fraction increases the volume expansion decreases. On the other hand, it is found that the pore fraction decreases as the volume expansion decreases. The fraction of primary austenite decreases as the fraction of carbon increases, and that leads to having a lower pore fraction.

• Periodical: Materials Science Forum (Volume 925)
• Pages: 140-146
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.925.140
• Online since: June 2018
• Authors: Abel Tesfaye Tadesse*, Hasse Fredriksson
• Keywords: Hyper-Eutectic, Hypo-Eutectic, LVDT, Nodular Cast Iron, Nodule Count, Solidification, Volume Change

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