Different groups work on the production of the resistant thin films like Ni, Cu, Zn and Ni-P alloy through codeposition of the solid particles such as Al2O3, SiC, TiO2, B4C and diamond nanoparticles during the plating process. 1,2 In this research, For the first time, simultaneous synthesis and deposition of ZnO nanoparticles (NPs) have been carried out upon the surface of electroless Ni-P (EN) layer in order to improve the anticorrosive performance. Ni-P alloy coating has been produced by electroless nickel (EN) plating from the acid bath on the surface of mild steel then zinc oxide as an anticorrosive metal oxide has been deposited on the EN plated surface under ultrasonic irradiation. Transferring of the acoustic energy to the medium leads to more uniform distribution of the fabricated particles on the surface. The morphology and the chemical composition of the final surfaces have been characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. Electrochemical methods including the linear polarization resistance (LPR), Tafel extrapolation and electrochemical impedance spectroscopy (EIS) have been applied to evaluate the corrosion resistance of the Ni-P coatings with and without ZnO NPs. Our results confirmed that the deposition of zinc oxide nanoparticles on the surface of EN deposit improves significantly the corrosion resistance properties.

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