Microstructure, tribological and mechanical strengthening effect of multiphase Zn/ZrO2-SiC electrodeposited composite coatings

In an attempt to improve the mechanical and thermal resilient properties of mild steel, Zn-ZrO2-SiC composite coating was fabricated from zinc-based sulphate electrolyte with incorporated composite particles of ZrO2/SiC at 2.0 A/cm2 for 10 min. The effects of particle on the mechanical properties were examined using scanning electron microscope attached with energy dispersion spectroscopy and atomic force microscopy. The micro-hardness and wear resistance behaviour were determined with high diamond micro-hardness tester and three body abrasive MTR-300 testers with dry sand rubber wheel apparatus with 5 N. The fabricated coating was thermally heated at 200 °C for 4 h to evaluate the coating stability. From the results, a modification in the microstructure and topographic orientation as a result of incorporated composite was noticed on the zinc matrix. The mechanical and thermal properties were observed to be considerably improved by the incorporation of the ZrO2/SiC weight fraction. A significant improvement in wear and hardness properties were also obtained for the multiphase embedded coatings.