An investigation of the erosion–corrosion characteristics of ductile cast iron

The erosion–corrosion wear characteristics and mechanism of martensitic ductile cast irons with different alloying compositions in quartz slurries with different pH values were determined and analysed. The results indicated that the erosion–corrosion wear resistance of martensitic ductile cast iron would be increased not only with the pH values of the slurry and the erosion angle, but also with the addition of copper, nickel and chromium elements, respectively. A few of eutectic carbides would appear in the microstructures of ductile cast iron when the chromium element is added into this cast iron. However, these carbides would harm the erosion–corrosion wear resistance of this cast iron in acidic slurry. The addition of Ni, Cu, Cr elements and increase of Si element content would be helpful to improve the erosion–corrosion wear resistance of this cast iron in neutral and alkaline slurry, especially for chromium. Because the hardness of ductile cast iron could be remarkably increased by the occurrence of carbides when the chromium element was added. The erosion–corrosion mechanisms of the martensitic ductile cast irons were dominated by particles erosion wear in alkaline and neutral slurries, and by the interaction of particle erosion wear and medium corrosion in acidic slurry.