Structure, microstructure and compositional analysis of electrodeposited Cu-Ni-W/ZrO2 metal matrix nanocomposite coatings

The study explored the impact of deposition parameters, particularly the amount of ZrO₂ particles and current density, on structure, microstructure and compositional attributes of Cu-Ni-W/ZrO₂ metal matrix nanocomposite coatings for their formulation as advanced materials. Nanocomposite coatings composed of Cu-Ni-W alloy matrix, reinforced with 8 mol% yttria-stabilized ZrO₂ ceramic particles, were successfully synthesized using the direct current electrodeposition method. The selected area electron diffraction patterns obtained from high-resolution transmission electron microscopy analysis have confirmed the presence of multiple crystallographic phases of ZrO₂ within the composite matrix. The diffraction spots were assigned to the (101), (002), (222), (331), and (114) crystallographic planes of the tetragonal phase, whereas the monoclinic phase was identified by the (−202) and (031) diffraction planes. Additionally, the (420) diffraction plane was associated with the cubic phase of ZrO₂. The X-ray diffraction analysis confirmed the presence of characteristic diffraction peaks at 2θ values of 43.7°, 50.9°, and 74.2°, which were attributed to the (111), (200), and (220) planes of the face-centred cubic structure of Cu-Ni-W. The field emission scanning electron microscopy images indicated that coatings consist of a highly refined, compact, and crack-free morphology with thickness of ∼340 to 420 nm. The findings from Energy Dispersive Spectroscopy confirmed that coatings were rich in copper, containing Cu 69–90 wt%, Ni 2–19 wt%, and W 1–5 wt%. Additionally, the concentration of incorporated ZrO₂ ceramic particles was found to vary between 1 and 9 wt% in the composite coatings. The Cu–Ni–W/ZrO₂ MMNC coatings demonstrated improved mechanical characteristics, as evidenced by a reduction in indentation depth from 76 to 51 nm and an increase in hardness to 5.5 GPa with the rise in ZrO₂ concentration from 5 to 30 g/L in the electrolyte. The maximum elastic modulus of 110 GPa, was attributed to phase multiplicity, grain refinement, and the rigid reinforcement of the ZrO₂ nanoparticles.