Effect of Current Density on the Microstructure and Performance of Super-Hydrophobic Ni-ZrO₂ Composites

This study presents the fabrication of Ni-ZrO₂ coatings via pulse electrodeposition at different current densities, followed by hydrophobic modification to enhance corrosion resistance. The surface morphology, phase structure, element distribution, abrasive behavior, corrosion resistance, and water contact angle (CA) of super-hydrophobic Ni-ZrO₂ coatings were investigated using a scanning electron microscope (SEM), x-ray diffractometer (XRD), energy-disperse spectroscopy (EDS), nano-indentation, ball-on-disk wear tester, electrochemical workstation, and contact angle meter. According to SEM and EDS data, the Ni-ZrO₂ composites fabricated at current density of 2 A/dm² developed a flat surface morphology and a high ZrO₂ content. Additionally, CA results suggested the Ni-ZrO₂ composites manufactured at current density of 2 A/dm² exhibited super-hydrophobic properties and excellent stability. XRD results indicated that ZrO₂ particles were successfully embedded in three Ni-ZrO₂ composites. Furthermore, the Ni-ZrO₂ composites prepared at current density of 2 A/dm² had the highest microhardness value at 527.3 HV and the lowest wear depth at 24.1 μm. In comparison with other two Ni-ZrO₂ composites, the Ni-ZrO₂ composites obtained at current density of 2 A/dm² displayed superior corrosion resistance, as evidenced by its corrosion potential of − 0.419 V and corrosion current of 1.356 µA/cm².