Synergistic Effect of Nano-CeO2 and Graphene Nanoplatelet Reinforcements on Characteristics and Wear Behavior of Cr3C2-NiCr Coatings

The current work investigates the effect of nano-CeO₂ (nCeO₂) and graphene nanoplatelet (GNP) reinforcements on the microstructural/mechanical characteristics and sliding wear (ball-on-disk) behavior of HVOF-sprayed Cr₃C₂-NiCr coatings. Commercially available Cr₃C₂-NiCr feedstock powders were blended with 1 wt.% nCeO₂ and 1 wt.% GNP powders. Advanced characterization was carried out using SEM/EDS, TEM, XRD, Raman Spectroscopy, and optical profilometry. The results reveal that addition of nCeO₂ and GNP to the coatings improved the microhardness and fracture toughness by 28% and 42% and lowered the porosity, COF, and specific wear rate by 69%, 42%, and 24%, respectively. Post-wear analysis reveals the synergistic role played by both nCeO₂ and GNP reinforcements in improving the tribological performance of the coatings.