The erosion of four materials using seven erodents - towards an understanding

In order that an overview of the erosion process be obtained, solid particle erosion tests on four materials have been performed using seven different erodents within a range of particle diameters D (63 to 1000 mu m), velocities V (33 m s(-1) to 99 m s(-1)) and impact angles alpha (30 degrees to 90 degrees). The materials are glass, alumina, WC-7% Co and 304 stainless steel. Seven erodents are steel shot, glass beads, silica, alumina, tungsten carbide, silicon carbide and diamond particles. Systematic studies of the influence of the impact variables on the erosion rate have been made. Scanning electron microscopy of the eroded surface and the erodents after impact has been performed. Empirical correlations between erosion rate and the parameters of erodents are obtained and discussed in terns of the modes and mechanisms of erosion. An analysis of these results reveals that for brittle materials, glass and alumina, the erosion rate is determined by kinetic energy, particle size and the relative hardness and toughness of erodents. However, for ductile materials, the shape and kinetic energy of erodents are the mast important factor; determining the erosion rate. There is no significant effect of hardness and toughness of erodents on erosion. An attempt to rationalise the results in terms of mechanisms has been made. (C) 1999 Elsevier Science S.A. All rights reserved.