Effect of Si content on SiO₂ particle erosion of spheroidal graphite cast iron

The effect of Si content on SiO₂ particle erosion wear of spheroidal graphite cast iron was studied. The present erosion tests were performed to provide an understanding of erosion wear resistance of spheroidal graphite (S.G.) cast iron, which is required for improving weather resistance by raising silicon content. An increased Si content promoted a decrease in the amount of the pearlite phase, thus decreasing the erosion resistance of as cast S.G. cast iron. An increased Si content hardens the ferrite phase, thereby improving the erosion resistance. The erosion rate of full pearlitic S.G. cast iron tends to increase as the Si content increases. The wear surface and subsurface morphologies which reflect the erosion wear process, an increase in erosion wear rate could be caused either by changes in the microstructure or by the variation of silicon content which almost did not alter the impact angle of maximum erosion rate of S.G. cast iron. It should be noted that the dominant factor on the erosion resistance was the presence of the pearlite structure in the materials despite the fact that the specimens may have different silicon contents.