Effect of Graphene Nanoparticles on Slurry Erosion Behavior of High-Velocity Oxy-Fuel (HVOF)-Sprayed Mo₂C and Co–Ni-Based Coatings Over SS304 Steel

The present study delves into the challenges of slurry erosion in hydropower plant components, particularly focusing on Stainless-Steel 304 (SS304) limitations under high-velocity conditions. It proposes Mo₂C coating combinations applied via High-Velocity Oxy-Fuel (HVOF) spraying as a promising solution due to their high hardness, wear, and corrosion resistance. Three coatings (Coating A, Coating B, and Coating C) were formulated with varying Mo₂C, Co–Ni, and graphene nanoparticles (GNP) percentages, demonstrating unique erosion-resistant properties. Microscopic analysis revealed wear mechanisms, with Coating A displaying particle breakage, Coating B exhibiting fractured Mo₂C particles, and Coating C showing dynamic interactions with GNP, enhancing resistance. The findings suggest that tailored coatings incorporating GNP offer potential for erosion resistance improvement, prompting further exploration into optimizing GNP concentrations, refining deposition techniques, and assessing long-term durability under diverse operational conditions.