Abstract
The present work gives a detailed analysis into one of the most important quality parameters in cast iron, namely the eutectic cells or nodule count. The analysis is based on theoretical fundamentals of cast iron solidification. Expressions are derived and used to relate either the number of cells or the nodule count to factors of technological importance. It is found that such factors are intrinsically related to the chill tendency, pre-shrinkage expansion, shrinkage porosity, shrinkage depression and graphite type. Also, it is shown that the resultant mechanical properties of cast iron are strongly influenced by the foundry practice. In particular, it is established that the eutectic cell density or the nodule count is a quality factor reflecting the physical-chemical state of the liquid cast iron at a given cooling rate. In turn, this determines the graphite nucleation potential of cast iron which can be used to incorporate all of the technological factors associated with melt preparation.
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Fraś, E., López, H. Eutectic Cells and Nodule Count—An Index of Molten Iron Quality. Inter Metalcast 4, 35–61 (2010). https://doi.org/10.1007/BF03355497
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DOI: https://doi.org/10.1007/BF03355497