Electrodeposition of Ni–W/Al₂O₃ Nano-Composites and the Influence of Al₂O₃ Incorporation on Mechanical and Corrosion Resistance Behaviours

Ni–W/Al 2 O 3 nano-composites were electrodeposited on mild steel substrate for mechanical and corrosion resistance applications. This study focused on the preparation of Ni–W/Al 2 O 3 nano-composite coating with various quantity of Al 2 O 3 incorporations. The addition of Al 2 O 3 in the electrolytes were varied from 1–10 g/L in electrolytes and the Al 2 O 3 incorporation in Ni–W/Al 2 O 3 nano-composite coatings were obtained from 1.82 to 13.86 wt.%. The incorporation of Al 2 O 3 in Ni–W alloy matrix influenced the grain size, surface morphology and structural properties were observed. The distributions of Al 2 O 3 particle in alloy matrix were confirmed using electron microscopy (FESEM and TEM) and EDAX mapping analysis. The crystal structure informations were studied using X-ray diffraction method and it confirms that the deposits having cubic crystal structure. The better corrosion rate (0.87 mpy) and microhardness (965 HV) properties were obtained for the Ni–W/Al 2 O 3 nano-composite coating with 13.86 wt.% of Al 2 O 3 incorporations.