Analysis of the relationships between the parameters of sphericity, compactness and the GAP parameter in nodular cast iron using X-ray micro-computed tomography and image processing

Abstract

This paper is an extension of previous investigation (Toledo, 2021). The present article is focused in the most detailed analysis of sphericity, compactness, and the GAP parameter, linking them with the spheroidal graphite nodules size. Data was obtained from an X-ray micro-computed tomography of a fully ferritic grade SGI 60-40-18 sample in order to generate 3D high-resolution images for their subsequent analysis. Based in a new subpopulation, a correlation is established between the first two parameters mentioned, and based on three previously defined subpopulation by the nodules size, it is analyzed how the GAP parameter evolves. The results reaffirm the combined use of sphericity and compactness parameters and add the use of the GAP parameter to determine the nodules quality, at the same time, they show a trend to clustering.