Fatigue crack propagation and damaging micromechanisms in Ductile Cast Irons

Abstract

The interest on the DCIs damaging mechanisms strongly increased, and the research activity was focused both the role played by the microstructure and on the influence of the graphite elements.In this work, the role played by the graphite elements during the fatigue crack propagation has been investigated by means of the analysis of the fatigue crack profiles in four different ductile cast irons. The experimental results demonstrate that the graphite elements can’t be merely considered as voids or rigid spheres embedded in a matrix and that they act as a sort of “attractors” of the fatigue crack.