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Ductile cast irons are widely used due to their interesting mechanicalproperties combination (high ductility, high tensile strength, good wear resistance).Graphite nodules peculiarities (roundness, referred to as nodularity, but also graphiteelements number per area unit and volume fraction) and matrix microstructure (bothchemical composition and heat treatment controlled) strongly affect mechanicalbehaviour and damaging micromechanisms, also considering very simple loadingconditions (e.g. tensile test conditions). Focusing ferritic ductile irons, matrix –graphite nodule debonding, and the consequent voids growth, is often identified as themain damaging micromechanism, and numerous studies provided analytical laws todescribe growth of a single void, depending on the void geometries and matrixbehaviour. In this work, ferritic DCI damaging micromechanisms were investigated,considering uniaxial tensile tests, and investigating the influence of triaxiality andstrain rate. Step by step tensile tests were performed on unnotched and notchedspecimens. Specimens surfaces were observed by means of a scanning electronmicroscope (SEM) during the test. Furthermore, tensile test were performedconsidering different deformation rates, performing a SEM observation of fracturesurfaces. Experimental results analysis confirm that matrix-graphite nodules debondingis only one of the damaging micromechanisms involved in ferritic ductile irons failure