Development of Nanostructured Ni–Fe Alloy Coatings; Characterisation and Corrosion Analysis

The present investigation deals with the electrofabrication of nanostructured Ni-Fe alloy coatings on a mild steel using sulfate bath. The electrolytic bath composition and the current density of the coatings were optimized. Composition analysis by energy dispersive X-ray spectroscopy revealed that the Ni–Fe alloy coatings are of anomalous type. Potentiodynamic polarization corrosion test and electrochemical impedance spectroscopy methods in 3.5% NaCl solution direct towards the lowest corrosion rate at 4 A dm –2 . Hardness and roughness of the coatings were evaluated using Vickers hardness test and atomic force microscopy, respectively. The surface morphological analysis of the coatings was characterized by scanning electron microscopy with energy dispersive X-ray spectroscopy. The phase structure, the texture coefficient, and the crystallite grain size of the coatings were calculated and studied using X-ray diffraction.