Morphology and Corrosion Behavior of Zn-Ni Layers Electrodeposited on Low Alloy Carbon Steel Substrate

Abstract

The aim of this work is to improve the microstructure, the morphology, the mechanical and the corrosion behavior of Zn-Ni layers electrodeposited on low alloy carbon steel. Some factors such as the nickel concentration in the electrolyte, the electrolyte temperature and the current density are studied and optimized. The efficiency of the layers to protect the low alloy carbon steel against corrosion in HCl solution is also studied in this work. The electrodeposited Zn-Ni layers morphologies and microstructure were investigated by Scanning Electronic Microscopy (SEM) and X-ray diffraction (XRD) respectively. The best deposits of Zn-Ni layers are obtained with 50%-Ni in the electrolyte bath at a temperature of 40°C and a current density of j = 3 A dm-2. The XRD spectrum showed the coexistence of two phases: δ-phase (Ni3Zn22) and γ-phase (Ni5Zn21), and a pyramidal morphology is detected by SEM. The lost mass method results showed that the corrosion rate tacked a steady state between 10 and 50% of Ni, and it increased with the increase of Ni amount in the electrolyte bath.

PANi/PPy and PANi Films on ZnNi Alloy Coated Carbon Steel; Electrochemical Syntheses and Corrosion Performances

“…Among these alloys, especially ZnNi alloy is studied more in the literature because of its excellent resistant characteristic to corrosive factors in the atmospheric environment, machining properties, weldability etc. (Abd El-Lateef et al 2015;Bhat et al 2021;Chouia et al 2021;Ozyilmaz et al 2020;Tozar and Karahan 2014) Considering the literature studies in recent years, it is seen that conductive polymers are of interest in the field of corrosion protection due to their unique properties such as superior anticorrosive properties, redox reactions in natural environment and catalytic activity. For this aim, polyaniline and polypyrrole among conducting polymers are use for the corrosion protection of metals in a wide range of aggressive environments (Ates 2016;Kaliyannan et al 2020;Sokolova et al 2017).…”