Erosion Wear Behavior of High Chromium Cast Irons

Abstract

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°, 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.