An investigation was carried out to determine the effect of nodular cast iron (NCI) microstructure on its cavitation corrosion behavior in natural seawater. The cavitation tests were conducted using cavitation induced facility at a frequency of 20 kHz on detached specimens. Morphological examinations on cavitated specimens indicated that the surface on NCI became very rough with large size caivity pits. Examinations by optical microscopy of cross-sectioned specimens revealed the presence of microcracks in the bottom of cavity pits. Localized material removal on the
NCI surface was due to ductile tearing and brittle modes of failure.
Keywords: cast iron, seawater, cavitation corrosion.