Erosion Wear Behavior of High Chromium Cast Irons

In this study, two high chromium cast irons (HCCI) with different chromium content (15%Cr and 25%Cr), in as-cast and annealed conditions (heat-treated, HT), were tested to determine the erosion wear behavior of these alloys. Erosion tests were done using a gas blast sand facility with high erodent particle velocity (90 m/s) and high erodent feed rate, at an impact angle of 45 degrees, which represents conditions similar to service conditions of some components of thermal power plants using pulverized high mineral content coals. To identify erosion mechanisms, microstructural characterization was done by a scanning electron microscope on samples before and after erosion tests. Identification of microstructural phases was done by X-ray diffraction analysis. The main results of the tests shown in this paper indicate that matrix plastic deformation and distribution of carbide phase have a significant contribution to erosion resistance of HCCI alloys in severe erosion service conditions.