Ruxanda R, Beltran-Sanchez L, Massone J, Stefanescu D M

Abstract: The sequence of solidification of spheroidal graphite iron is discussed based on existing theories. Then, using the results of SEM investigation of micro-shrinkage regions in thin plates ductile iron, and of metallographic investigation using color- etching metallography, the authors provide a detailed description of the eutectic grain in ductile iron. It was found that the eutectic structure of ductile iron includes primary austenite dendrites as well as eutectic dendrites containing several nodules. A computational solidification model that describes microstructure evolution of the multi-nodule eutectic grains in ductile iron was also proposed. The model generates calculated microstructures that correctly depict the experimental microstructure obtained through SEM and color-etching metallography.

Keywords: Spheroidal graphite iron, Eutectic solidification, Experimental, Mathematical modeling approach.