Graphite Nodules Influence on DCIs Mechanical Properties: Experimental and Numerical Investigation

Ductile cast irons (DCIs) are characterized by very interesting properties, with a good castability (typical of cast irons) and a very interesting mechanical behaviour, that is comparable to low alloyed steels. From the point of view of the microstructure, these alloys can be considered as natural composites, with graphite nodules embedded in a metal matrix. Their mechanical properties are influenced both by the matrix microstructure (e.g., ferrite, pearlite, ferrite-pearlite, austenite, etc.) and by the morphological peculiarities of the graphite elements (nodularity, element distribution, dimensions etc.). In this work, an experimental and numerical procedure has been optimized in order to obtain a 3D representation of a ferritic DCI considering the effective distribution of the graphite elements. Starting from this 3D representation, the behavior of the investigated DCI has been simulated by means of finite elements approach.