The role of particle size and solids concentration on the transition from moderate to severe slurry wear regimes of ASTM A743 grade CA6NM stainless steel

The role of particle size and solids concentration on the slurry erosion of a stainless steel was studied with base in laboratory tests and data from field inspections of two Pelton turbines. The slurry for the laboratory tests was composed of water and SiO2 sand particles with mean diameter ranging from 50 to 655 μm and solids concentrations up to 1200 mg l−1. The wear rate increased linearly with solids concentration within the range studied, while the sensitivity of the surface to changes in erosive particle size decreased with the particle size. A critical particle size range for the moderate-to-severe wear regime transition was found, which is practically unaffected by the variety of solids concentrations considered in this study.