ABSTRACT.A wide range of metal-oxides exhibit fascinating properties and multiple functionalities that could address challenge of physical and mechanical deterioration of materials in service. In this study, Zn-ZrO2, Zn-SiC and Zn-ZrO2-SiC composite coating was fabricated from zinc based sulphate electrolyte at constant current density, depth of immersion, distance between anode and cathode with time of deposition. The effect of particle on the physical behaviour of the coating was examined by coating gauge tester for the coating thickness and coating texture. The mechanical properties in term of hardness and wear characteristics were examined using high diamond micro-hardness tester and three body abrasive MTR-300 testers with dry sand rubber wheel apparatus with 5 N and 15 N, respectively. The coating stability in harsh region was examined with isothermal furnace at 200 o C for 4 h. The structural behaviour was investigated using scanning electron microscope attached with energy dispersion spectroscopy (SEM/EDS). The result shows that significant improvements in wear and hardness properties are linked to the microstructural modification of the coating as a result of the embedded particulate. The strengthening behaviour was improved with about 98% of coating efficiency. The progression of the coating thickness and texture were in line with other results obtained.

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In anticipation for resolution of deterioration catastrophe on metallic materials, researches in the field of corrosion remains. Zn–Ni–NbO2 deposits were obtained on mild steel substrate using D.C. power source. The thermal stability properties of the coatings were determined by micro-hardness evaluations before and after heat treatment at 250 and 350 °C. The surface structure analysis was done by Scanning Electron Microscope and X-ray diffraction while the wear evaluations were obtained and compared. The weight gain and coating thickness were obtained and found to be in correlation with the wear results. The coating developed in this study is recommended for metallic surface improvement engineering applications.

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