Characterization of defects and graphite types in ductile cast iron by image processing and its relation to mechanical properties

The paper presents a fast and reliable image processing tool to characterize graphite nodules and casting defects in ductile cast iron (IAOGT – Image Analysis of Graphite Types). Relationship between ductility of ductile cast iron and size of casting defects and different characteristic nodule properties (graphite type, feret, nodularity and nodule count) are indicated by analysis of 33 tested tensile specimens. The casting defects andvariation in nodule properties interact in a complex way but casting defects in the form of oxide films contribute most to low ductility. Low nodularity and low nodule count and high feret of graphite type III, IV-V also reduce ductility.JRC.F.4-Nuclear design safet