Role of microscale and nanoscale CeO2 particles on the microstructures, internal stress and properties in electrodeposited NiCo alloy platings

In this study, a thorough investigation was undertaken to explore the effects of microscale and nanoscale CeO₂ particles on the characteristics of NiCo-CeO₂ composite platings, including their surface features, microstructure, internal stress, and overall performance. The results indicated that microscale platings had a higher content of CeO₂, as well as increased surface roughness, when compared to nanoscale platings. Additionally, microscale particles were found to effectively prevent the growth of columnar crystals and refine grain structure, thus reducing the texture in microscale platings. Conversely, nanoscale particles were more efficient in inhibiting texture, which promoted a more uniform microstructure in the nanoscale platings. Incorporating CeO₂ particles into the alloy platings increased the internal stress within the composite plating. Moreover, the microscale platings showed greater internal stress and variation in comparison with the nanoscale ones. The addition of microscale particles enhanced the surface microhardness of the NiCo-CeO₂ composite platings, whereas nanoscale particles led to a more evenly distributed microhardness across the plating. Notably, the corrosion resistance of the nanoscale platings surpassed that of the microscale platings.