Abstract
The suggested approaches, including an automated SEM/EDX (Scanning Electron Microscopy/Energy Dispersive X-ray) analysis of graphite nodule nuclei and a special algorithm to convert two-dimensional to three-dimensional graphite nodule size distribution, were tested. The “soft” quenching technique was applied to develop small graphite nodules and increase probability to reveal non-metallic heterogeneous nuclei using automated SEM/EDX analysis. Ternary diagrams present experimental statistics of the graphite nuclei chemistry. A special algorithm for the conversion of diameters of two-dimensional sections of graphite nodules to the real three-dimensional distribution of spherical particles was developed. This algorithm is based on inverse simulation. The developed program calculates a three-dimensional nodule diameter distribution curve, the real average diameter, and volumetric nodule number. The examples of practical applications of these methods for spherical graphite characterization in different ductile iron castings are provided. Heterogeneous nucleation of graphite nodules is discussed based on the novel experimental data.
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Lekakh, S., Harris, M. Novel Approaches to Analyze Structure of Ductile Iron. Inter Metalcast 8, 41–49 (2014). https://doi.org/10.1007/BF03355581
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DOI: https://doi.org/10.1007/BF03355581