Enhanced tribomechanical and electrochemical performance of the Ni–P electrodeposits reinforced by duplex Cr2O3 and ZrO2 ceramic nanoparticles

The deposition of efficient protective coatings not only prolongs the in-service lifetime of the engineering parts but also improves their performance. In this survey, the Ni–P–Cr 2 O 3 –ZrO 2 nanocomposite layers were galvanostatically electrodeposited from the controlled Watts bath consisting of 0–8 g/L of the nanoparticles on the St37 steel electrodes using direct current (DC) at 175 mA/cm 2 . Surface and microstructural features of the layers were assessed by the FESEM, EDS, AFM, and XRD. Co-deposited nanoparticles had no influence on the phase structure but changed the morphology of the grains, decreased the P content, and made the surface smoother. Tribomechanical properties of the deposits were evaluated by the Vickers microhardness and pin-on-disk routes, and the results confirmed a considerable increment with the included duplex ceramic nanoparticles. The COF value decreased by 0.47, while an approx. 265 HV increment was obtained in microhardness value. Results of the anti-corrosion performance of the layers that were studied by the potentiodynamic polarization (PDP) assay illustrated a drop in corrosion current density and a rise in corrosion potential by ~ 85% and ≈34%, respectively, with the addition of 4 g/L of the duplex nanoparticles to the Ni–P bath. Results paved the way for the successful inclusion of the duplex nanoparticles in the microstructure of the Ni–P electrodeposits, leading to the better performance of the layers.