Effect of impact angle on the slurry erosion-corrosion of Stellite 6 and SS316

This study is an investigation of the effect of impingement angle on slurry erosion-corrosion of Stellite 6 manufactured by sand casting, lost wax casting and SS316. The tests were performed using an impingement rig in which a slurry with 3.5% NaCl and 1.177g/l suspended angular sand particles at 19m/s were recirculated for one hour. The results were obtained for angles of 20°, 45°, 60° and 90° to the exposed surface. Post experimental analysis using light microscopy, surface profiling and SEM assisted with clarification of the wear mechanisms and assessment of the severity of surface damage. Stellite 6 consistently exhibited superior wear resistance compared with SS316. The most severe regime for SS316 was experienced at low angle of impingement, 45°, due to its ductility. Alternatively, the brittle network of chromium carbides showed significant impact on the behaviour of cast Stellite 6 under solid-liquid impingement with the most critical erosion-corrosion damage occurring at 60°.