Synthesis and Characterization of Cr-ZrO2 Composite Coating Formed by DC and Pulse Electrodeposition

Chromium–zirconia (Cr-ZrO₂) composite coatings were developed on low-carbon steel substrate by direct current (DC) and pulse electrodeposition (PED) technique with different pulse frequency and duty cycles to enhance mechanical properties of the coating. The phases and morphology of the coating were studied with scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. Surface mechanical properties were analyzed by micro-hardness and ball-on-plate wear study. It was found that pulsing and higher pulse frequencies refine the matrix and increase the ZrO₂ content in the coating. Apart from fine structure and dispersion, crystallographic orientation of Cr matrix also gives its effect on hardness and wear properties. Wear mechanism was found to be mainly abrasive in nature with little adhesive inclination in case of DC deposition.